Test `trim on SET with big value` (introduced from #11817) fails under mac m1 with libc mem_allocator.
The reason is that malloc(33000) will allocate 65536 bytes(>42000).
This test still passes under ubuntu with libc mem_allocator.
```
*** [err]: trim on SET with big value in tests/unit/type/string.tcl
Expected [r memory usage key] < 42000 (context: type source line 471 file /Users/iospack/data/redis_fork/tests/unit/type/string.tcl cmd {assert {[r memory usage key] < 42000}} proc ::test)
```
simple test under mac m1 with libc mem_allocator:
```c
void *p = zmalloc(33000);
printf("malloc size: %zu\n", zmalloc_size(p));
# output
malloc size: 65536
```
As `sdsRemoveFreeSpace` have an impact on performance even if it is a no-op (see details at #11508).
Only call the function when there is a possibility that the string contains free space.
* For strings coming from the network, it's only if they're bigger than PROTO_MBULK_BIG_ARG
* For strings coming from scripts, it's only if they're smaller than LUA_CMD_OBJCACHE_MAX_LEN
* For strings coming from modules, it could be anything.
Co-authored-by: Oran Agra <oran@redislabs.com>
Co-authored-by: sundb <sundbcn@gmail.com>
* Make it clear that current_client is the root client that was called by
external connection
* add executing_client which is the client that runs the current command
(can be a module or a script)
* Remove script_caller that was used for commands that have CLIENT_SCRIPT
to get the client that called the script. in most cases, that's the current_client,
and in others (when being called from a module), it could be an intermediate
client when we actually want the original one used by the external connection.
bugfixes:
* RM_Call with C flag should log ACL errors with the requested user rather than
the one used by the original client, this also solves a crash when RM_Call is used
with C flag from a detached thread safe context.
* addACLLogEntry would have logged info about the script_caller, but in case the
script was issued by a module command we actually want the current_client. the
exception is when RM_Call is called from a timer event, in which case we don't
have a current_client.
behavior changes:
* client side tracking for scripts now tracks the keys that are read by the script
instead of the keys that are declared by the caller for EVAL
other changes:
* Log both current_client and executing_client in the crash log.
* remove prepareLuaClient and resetLuaClient, being dead code that was forgotten.
* remove scriptTimeSnapshot and snapshot_time and instead add cmd_time_snapshot
that serves all commands and is reset only when execution nesting starts.
* remove code to propagate CLIENT_FORCE_REPL from the executed command
to the script caller since scripts aren't propagated anyway these days and anyway
this flag wouldn't have had an effect since CLIENT_PREVENT_PROP is added by scriptResetRun.
* fix a module GIL violation issue in afterSleep that was introduced in #10300 (unreleased)
All of the POP commands must not decr length below 0.
So, get_fsl will delete the key if the length is 0 (unless
the caller wished to create if doesn't exist)
Other:
1. Use REDISMODULE_WRITE where needed (POP commands)
2. Use wait_for_blokced_clients in test
Unrelated:
Use quotes instead of curly braces in zset.tcl, for variable expansion
The PR adds support for the following flags on RedisModule_OpenKey:
* REDISMODULE_OPEN_KEY_NONOTIFY - Don't trigger keyspace event on key misses.
* REDISMODULE_OPEN_KEY_NOSTATS - Don't update keyspace hits/misses counters.
* REDISMODULE_OPEN_KEY_NOEXPIRE - Avoid deleting lazy expired keys.
* REDISMODULE_OPEN_KEY_NOEFFECTS - Avoid any effects from fetching the key
In addition, added `RM_GetOpenKeyModesAll`, which returns the mask of all
supported OpenKey modes. This allows the module to check, in runtime, which
OpenKey modes are supported by the current Redis instance.
TLDR: solve a problem introduced in Redis 7.0.6 (#11541) with
RM_CommandFilterArgInsert being called from scripts, which can
lead to memory corruption.
Libc realloc can return the same pointer even if the size was changed. The code in
freeLuaRedisArgv had an assumption that if the pointer didn't change, then the
allocation didn't change, and the cache can still be reused.
However, if rewriteClientCommandArgument or RM_CommandFilterArgInsert were
used, it could be that we realloced the argv array, and the pointer didn't change, then
a consecutive command being executed from Lua can use that argv cache reaching
beyond its size.
This was actually only possible with modules, since the decision to realloc was based
on argc, rather than argv_len.
*TL;DR*
---------------------------------------
Following the discussion over the issue [#7551](https://github.com/redis/redis/issues/7551)
We decided to refactor the client blocking code to eliminate some of the code duplications
and to rebuild the infrastructure better for future key blocking cases.
*In this PR*
---------------------------------------
1. reprocess the command once a client becomes unblocked on key (instead of running
custom code for the unblocked path that's different than the one that would have run if
blocking wasn't needed)
2. eliminate some (now) irrelevant code for handling unblocking lists/zsets/streams etc...
3. modify some tests to intercept the error in cases of error on reprocess after unblock (see
details in the notes section below)
4. replace '$' on the client argv with current stream id. Since once we reprocess the stream
XREAD we need to read from the last msg and not wait for new msg in order to prevent
endless block loop.
5. Added statistics to the info "Clients" section to report the:
* `total_blocking_keys` - number of blocking keys
* `total_blocking_keys_on_nokey` - number of blocking keys which have at least 1 client
which would like
to be unblocked on when the key is deleted.
6. Avoid expiring unblocked key during unblock. Previously we used to lookup the unblocked key
which might have been expired during the lookup. Now we lookup the key using NOTOUCH and
NOEXPIRE to avoid deleting it at this point, so propagating commands in blocked.c is no longer needed.
7. deprecated command flags. We decided to remove the CMD_CALL_STATS and CMD_CALL_SLOWLOG
and make an explicit verification in the call() function in order to decide if stats update should take place.
This should simplify the logic and also mitigate existing issues: for example module calls which are
triggered as part of AOF loading might still report stats even though they are called during AOF loading.
*Behavior changes*
---------------------------------------------------
1. As this implementation prevents writing dedicated code handling unblocked streams/lists/zsets,
since we now re-process the command once the client is unblocked some errors will be reported differently.
The old implementation used to issue
``UNBLOCKED the stream key no longer exists``
in the following cases:
- The stream key has been deleted (ie. calling DEL)
- The stream and group existed but the key type was changed by overriding it (ie. with set command)
- The key not longer exists after we swapdb with a db which does not contains this key
- After swapdb when the new db has this key but with different type.
In the new implementation the reported errors will be the same as if the command was processed after effect:
**NOGROUP** - in case key no longer exists, or **WRONGTYPE** in case the key was overridden with a different type.
2. Reprocessing the command means that some checks will be reevaluated once the
client is unblocked.
For example, ACL rules might change since the command originally was executed and
will fail once the client is unblocked.
Another example is OOM condition checks which might enable the command to run and
block but fail the command reprocess once the client is unblocked.
3. One of the changes in this PR is that no command stats are being updated once the
command is blocked (all stats will be updated once the client is unblocked). This implies
that when we have many clients blocked, users will no longer be able to get that information
from the command stats. However the information can still be gathered from the client list.
**Client blocking**
---------------------------------------------------
the blocking on key will still be triggered the same way as it is done today.
in order to block the current client on list of keys, the call to
blockForKeys will still need to be made which will perform the same as it is today:
* add the client to the list of blocked clients on each key
* keep the key with a matching list node (position in the global blocking clients list for that key)
in the client private blocking key dict.
* flag the client with CLIENT_BLOCKED
* update blocking statistics
* register the client on the timeout table
**Key Unblock**
---------------------------------------------------
Unblocking a specific key will be triggered (same as today) by calling signalKeyAsReady.
the implementation in that part will stay the same as today - adding the key to the global readyList.
The reason to maintain the readyList (as apposed to iterating over all clients blocked on the specific key)
is in order to keep the signal operation as short as possible, since it is called during the command processing.
The main change is that instead of going through a dedicated code path that operates the blocked command
we will just call processPendingCommandsAndResetClient.
**ClientUnblock (keys)**
---------------------------------------------------
1. Unblocking clients on keys will be triggered after command is
processed and during the beforeSleep
8. the general schema is:
9. For each key *k* in the readyList:
```
For each client *c* which is blocked on *k*:
in case either:
1. *k* exists AND the *k* type matches the current client blocking type
OR
2. *k* exists and *c* is blocked on module command
OR
3. *k* does not exists and *c* was blocked with the flag
unblock_on_deleted_key
do:
1. remove the client from the list of clients blocked on this key
2. remove the blocking list node from the client blocking key dict
3. remove the client from the timeout list
10. queue the client on the unblocked_clients list
11. *NEW*: call processCommandAndResetClient(c);
```
*NOTE:* for module blocked clients we will still call the moduleUnblockClientByHandle
which will queue the client for processing in moduleUnblockedClients list.
**Process Unblocked clients**
---------------------------------------------------
The process of all unblocked clients is done in the beforeSleep and no change is planned
in that part.
The general schema will be:
For each client *c* in server.unblocked_clients:
* remove client from the server.unblocked_clients
* set back the client readHandler
* continue processing the pending command and input buffer.
*Some notes regarding the new implementation*
---------------------------------------------------
1. Although it was proposed, it is currently difficult to remove the
read handler from the client while it is blocked.
The reason is that a blocked client should be unblocked when it is
disconnected, or we might consume data into void.
2. While this PR mainly keep the current blocking logic as-is, there
might be some future additions to the infrastructure that we would
like to have:
- allow non-preemptive blocking of client - sometimes we can think
that a new kind of blocking can be expected to not be preempt. for
example lets imagine we hold some keys on disk and when a command
needs to process them it will block until the keys are uploaded.
in this case we will want the client to not disconnect or be
unblocked until the process is completed (remove the client read
handler, prevent client timeout, disable unblock via debug command etc...).
- allow generic blocking based on command declared keys - we might
want to add a hook before command processing to check if any of the
declared keys require the command to block. this way it would be
easier to add new kinds of key-based blocking mechanisms.
Co-authored-by: Oran Agra <oran@redislabs.com>
Signed-off-by: Ran Shidlansik <ranshid@amazon.com>
1. Get rid of server.core_propagates - we can just rely on module/call nesting levels
2. Rename in_nested_call to execution_nesting and update the comment
3. Remove module_ctx_nesting (redundant, we can use execution_nesting)
4. Modify postExecutionUnitOperations according to the comment (The main purpose of this PR)
5. trackingHandlePendingKeyInvalidations: Check the nesting level inside this function
In #11290, we added listpack encoding for SET object.
But forgot to support it in zuiFind, causes ZINTER, ZINTERSTORE,
ZINTERCARD, ZIDFF, ZDIFFSTORE to crash.
And forgot to support it in RM_ScanKey, causes it hang.
This PR add support SET listpack in zuiFind, and in RM_ScanKey.
And add tests for related commands to cover this case.
Other changes:
- There is no reason for zuiFind to go into the internals of the SET.
It can simply use setTypeIsMember and don't care about encoding.
- Remove the `#include "intset.h"` from server.h reduce the chance of
accidental intset API use.
- Move setTypeAddAux, setTypeRemoveAux and setTypeIsMemberAux
interfaces to the header.
- In scanGenericCommand, use setTypeInitIterator and setTypeNext
to handle OBJ_SET scan.
- In RM_ScanKey, improve hash scan mode, use lpGetValue like zset,
they can share code and better performance.
The zuiFind part fixes#11578
Co-authored-by: Oran Agra <oran@redislabs.com>
Co-authored-by: Viktor Söderqvist <viktor.soderqvist@est.tech>
From https://en.wikipedia.org/wiki/NaN#Display, it says
that apart from nan and -nan, we can also get NAN and even
nan(char-sequence) from libc.
In #11482, our conclusion was that we wanna normalize it in
Redis to a single nan type, like we already normalized inf.
For this, we also reverted the assert_match part of the test
added in #11506, using assert_equal to validate the changes.
Add a new module event `RedisModule_Event_Key`, this event is fired
when a key is removed from the keyspace.
The event includes an open key that can be used for reading the key before
it is removed. Modules can also extract the key-name, and use RM_Open
or RM_Call to access key from within that event, but shouldn't modify anything
from within this event.
The following sub events are available:
- `REDISMODULE_SUBEVENT_KEY_DELETED`
- `REDISMODULE_SUBEVENT_KEY_EXPIRED`
- `REDISMODULE_SUBEVENT_KEY_EVICTED`
- `REDISMODULE_SUBEVENT_KEY_OVERWRITE`
The data pointer can be casted to a RedisModuleKeyInfo structure
with the following fields:
```
RedisModuleKey *key; // Opened Key
```
### internals
* We also add two dict functions:
`dictTwoPhaseUnlinkFind` finds an element from the table, also get the plink of the entry.
The entry is returned if the element is found. The user should later call `dictTwoPhaseUnlinkFree`
with it in order to unlink and release it. Otherwise if the key is not found, NULL is returned.
These two functions should be used in pair. `dictTwoPhaseUnlinkFind` pauses rehash and
`dictTwoPhaseUnlinkFree` resumes rehash.
* We change `dbOverwrite` to `dbReplaceValue` which just replaces the value of the key and
doesn't fire any events. The "overwrite" part (which emits events) is just when called from `setKey`,
the other places that called dbOverwrite were ones that just update the value in-place (INCR*, SPOP,
and dbUnshareStringValue). This should not have any real impact since `moduleNotifyKeyUnlink` and
`signalDeletedKeyAsReady` wouldn't have mattered in these cases anyway (i.e. module keys and
stream keys didn't have direct calls to dbOverwrite)
* since we allow doing RM_OpenKey from withing these callbacks, we temporarily disable lazy expiry.
* We also temporarily disable lazy expiry when we are in unlink/unlink2 callback and keyspace
notification callback.
* Move special definitions to the top of redismodule.h
This is needed to resolve compilation errors with RedisModuleKeyInfoV1
that carries a RedisModuleKey member.
Co-authored-by: Oran Agra <oran@redislabs.com>
### Summary of API additions
* `RedisModule_AddPostNotificationJob` - new API to call inside a key space
notification (and on more locations in the future) and allow to add a post job as describe above.
* New module option, `REDISMODULE_OPTIONS_ALLOW_NESTED_KEYSPACE_NOTIFICATIONS`,
allows to disable Redis protection of nested key-space notifications.
* `RedisModule_GetModuleOptionsAll` - gets the mask of all supported module options so a module
will be able to check if a given option is supported by the current running Redis instance.
### Background
The following PR is a proposal of handling write operations inside module key space notifications.
After a lot of discussions we came to a conclusion that module should not perform any write
operations on key space notification.
Some examples of issues that such write operation can cause are describe on the following links:
* Bad replication oreder - https://github.com/redis/redis/pull/10969
* Used after free - https://github.com/redis/redis/pull/10969#issuecomment-1223771006
* Used after free - https://github.com/redis/redis/pull/9406#issuecomment-1221684054
There are probably more issues that are yet to be discovered. The underline problem with writing
inside key space notification is that the notification runs synchronously, this means that the notification
code will be executed in the middle on Redis logic (commands logic, eviction, expire).
Redis **do not assume** that the data might change while running the logic and such changes
can crash Redis or cause unexpected behaviour.
The solution is to state that modules **should not** perform any write command inside key space
notification (we can chose whether or not we want to force it). To still cover the use-case where
module wants to perform a write operation as a reaction to key space notifications, we introduce
a new API , `RedisModule_AddPostNotificationJob`, that allows to register a callback that will be
called by Redis when the following conditions hold:
* It is safe to perform any write operation.
* The job will be called atomically along side the operation that triggers it (in our case, key
space notification).
Module can use this new API to safely perform any write operation and still achieve atomicity
between the notification and the write.
Although currently the API is supported on key space notifications, the API is written in a generic
way so that in the future we will be able to use it on other places (server events for example).
### Technical Details
Whenever a module uses `RedisModule_AddPostNotificationJob` the callback is added to a list
of callbacks (called `modulePostExecUnitJobs`) that need to be invoke after the current execution
unit ends (whether its a command, eviction, or active expire). In order to trigger those callback
atomically with the notification effect, we call those callbacks on `postExecutionUnitOperations`
(which was `propagatePendingCommands` before this PR). The new function fires the post jobs
and then calls `propagatePendingCommands`.
If the callback perform more operations that triggers more key space notifications. Those keys
space notifications might register more callbacks. Those callbacks will be added to the end
of `modulePostExecUnitJobs` list and will be invoke atomically after the current callback ends.
This raises a concerns of entering an infinite loops, we consider infinite loops as a logical bug
that need to be fixed in the module, an attempt to protect against infinite loops by halting the
execution could result in violation of the feature correctness and so **Redis will make no attempt
to protect the module from infinite loops**
In addition, currently key space notifications are not nested. Some modules might want to allow
nesting key-space notifications. To allow that and keep backward compatibility, we introduce a
new module option called `REDISMODULE_OPTIONS_ALLOW_NESTED_KEYSPACE_NOTIFICATIONS`.
Setting this option will disable the Redis key-space notifications nesting protection and will
pass this responsibility to the module.
### Redis infrastructure
This PR promotes the existing `propagatePendingCommands` to an "Execution Unit" concept,
which is called after each atomic unit of execution,
Co-authored-by: Oran Agra <oran@redislabs.com>
Co-authored-by: Yossi Gottlieb <yossigo@gmail.com>
Co-authored-by: Madelyn Olson <34459052+madolson@users.noreply.github.com>
Improve memory efficiency of list keys
## Description of the feature
The new listpack encoding uses the old `list-max-listpack-size` config
to perform the conversion, which we can think it of as a node inside a
quicklist, but without 80 bytes overhead (internal fragmentation included)
of quicklist and quicklistNode structs.
For example, a list key with 5 items of 10 chars each, now takes 128 bytes
instead of 208 it used to take.
## Conversion rules
* Convert listpack to quicklist
When the listpack length or size reaches the `list-max-listpack-size` limit,
it will be converted to a quicklist.
* Convert quicklist to listpack
When a quicklist has only one node, and its length or size is reduced to half
of the `list-max-listpack-size` limit, it will be converted to a listpack.
This is done to avoid frequent conversions when we add or remove at the bounding size or length.
## Interface changes
1. add list entry param to listTypeSetIteratorDirection
When list encoding is listpack, `listTypeIterator->lpi` points to the next entry of current entry,
so when changing the direction, we need to use the current node (listTypeEntry->p) to
update `listTypeIterator->lpi` to the next node in the reverse direction.
## Benchmark
### Listpack VS Quicklist with one node
* LPUSH - roughly 0.3% improvement
* LRANGE - roughly 13% improvement
### Both are quicklist
* LRANGE - roughly 3% improvement
* LRANGE without pipeline - roughly 3% improvement
From the benchmark, as we can see from the results
1. When list is quicklist encoding, LRANGE improves performance by <5%.
2. When list is listpack encoding, LRANGE improves performance by ~13%,
the main enhancement is brought by `addListListpackRangeReply()`.
## Memory usage
1M lists(key:0~key:1000000) with 5 items of 10 chars ("hellohello") each.
shows memory usage down by 35.49%, from 214MB to 138MB.
## Note
1. Add conversion callback to support doing some work before conversion
Since the quicklist iterator decompresses the current node when it is released, we can
no longer decompress the quicklist after we convert the list.
The test introduced in #11482 fail on ARM (extra CI):
```
*** [err]: RESP2: RM_ReplyWithDouble: NaN in tests/unit/moduleapi/reply.tcl
Expected '-nan' to be equal to 'nan' (context: type eval line 3 cmd
{assert_equal "-nan" [r rw.double 0 0]} proc ::test)
*** [err]: RESP3: RM_ReplyWithDouble: NaN in tests/unit/moduleapi/reply.tcl
Expected ',-nan' to be equal to ',nan' (context: type eval line 8 cmd
{assert_equal ",-nan" [r rw.double 0 0]} proc ::test)
```
It looks like there is no negative nan on ARM.
In moduleFireServerEvent we change the real client DB to 0 on freeClient in case the event is REDISMODULE_EVENT_CLIENT_CHANGE.
It results in a crash if the client is blocked on a key on other than DB 0.
The DB change is not necessary even for module-client, as we set its DB to 0 on either createClient or moduleReleaseTempClient.
Co-authored-by: Madelyn Olson <34459052+madolson@users.noreply.github.com>
Co-authored-by: Binbin <binloveplay1314@qq.com>
The test introduced in #11482 fail on mac:
```
*** [err]: RESP3: RM_ReplyWithDouble: inf in tests/unit/moduleapi/reply.tcl
Expected 'Inf' to be equal to 'inf'
(context: type eval line 6 cmd {assert_equal Inf [r rw.double inf]} proc ::test)
```
Looks like the mac platform returns inf instead of Inf in this case, this PR
uses readraw to verify the protocol.
Adding a test to cover the already existing behavior of NAN replies,
to accompany the PR that adds them to the RESP3 spec:
https://github.com/redis/redis-specifications/pull/10
This PR also covers Inf replies that are already in the spec, as well as RESP2 coverage.
RM_Call is designed to let modules call redis commands disregarding the
OOM state (the module is responsible to declare its command flags to redis,
or perform the necessary checks).
The other (new) alternative is to pass the "M" flag to RM_Call so that redis can
OOM reject commands implicitly.
However, Currently, RM_Call enforces OOM on scripts (excluding scripts that
declared `allow-oom`) in all cases, regardless of the RM_Call "M" flag being present.
This PR fixes scripts to be consistent with other commands being executed by RM_Call.
It modifies the flow in effect treats scripts as if they if they have the ALLOW_OOM script
flag, if the "M" flag is not passed (i.e. no OOM checking is being performed by RM_Call,
so no OOM checking should be done on script).
Co-authored-by: Oran Agra <oran@redislabs.com>
In the module, we will reuse the list iterator entry for RM_ListDelete, but `listTypeDelete` will only update
`quicklistEntry->zi` but not `quicklistEntry->node`, which will result in `quicklistEntry->node` pointing to
a freed memory address if the quicklist node is deleted.
This PR sync `key->u.list.index` and `key->u.list.entry` to list iterator after `RM_ListDelete`.
This PR also optimizes the release code of the original list iterator.
Co-authored-by: Viktor Söderqvist <viktor@zuiderkwast.se>
The use case is a module that wants to implement a blocking command on a key that
necessarily exists and wants to unblock the client in case the key is deleted (much like
what we implemented for XREADGROUP in #10306)
New module API:
* RedisModule_BlockClientOnKeysWithFlags
Flags:
* REDISMODULE_BLOCK_UNBLOCK_NONE
* REDISMODULE_BLOCK_UNBLOCK_DELETED
### Detailed description of code changes
blocked.c:
1. Both module and stream functions are called whether the key exists or not, regardless of
its type. We do that in order to allow modules/stream to unblock the client in case the key
is no longer present or has changed type (the behavior for streams didn't change, just code
that moved into serveClientsBlockedOnStreamKey)
2. Make sure afterCommand is called in serveClientsBlockedOnKeyByModule, in order to propagate
actions from moduleTryServeClientBlockedOnKey.
3. handleClientsBlockedOnKeys: call propagatePendingCommands directly after lookupKeyReadWithFlags
to prevent a possible lazy-expire DEL from being mixed with any command propagated by the
preceding functions.
4. blockForKeys: Caller can specifiy that it wants to be awakened if key is deleted.
Minor optimizations (use dictAddRaw).
5. signalKeyAsReady became signalKeyAsReadyLogic which can take a boolean in case the key is deleted.
It will only signal if there's at least one client that awaits key deletion (to save calls to
handleClientsBlockedOnKeys).
Minor optimizations (use dictAddRaw)
db.c:
1. scanDatabaseForDeletedStreams is now scanDatabaseForDeletedKeys and will signalKeyAsReady
for any key that was removed from the database or changed type. It is the responsibility of the code
in blocked.c to ignore or act on deleted/type-changed keys.
2. Use the new signalDeletedKeyAsReady where needed
blockedonkey.c + tcl:
1. Added test of new capabilities (FSL.BPOPGT now requires the key to exist in order to work)
### Background
The issue is that when saving an RDB with module AUX data, the module AUX metadata
(moduleid, when, ...) is saved to the RDB even though the module did not saved any actual data.
This prevent loading the RDB in the absence of the module (although there is no actual data in
the RDB that requires the module to be loaded).
### Solution
The solution suggested in this PR is that module AUX will be saved on the RDB only if the module
actually saved something during `aux_save` function.
To support backward compatibility, we introduce `aux_save2` callback that acts the same as
`aux_save` with the tiny change of avoid saving the aux field if no data was actually saved by
the module. Modules can use the new API to make sure that if they have no data to save,
then it will be possible to load the created RDB even without the module.
### Concerns
A module may register for the aux load and save hooks just in order to be notified when
saving or loading starts or completed (there are better ways to do that, but it still possible
that someone used it).
However, if a module didn't save a single field in the save callback, it means it's not allowed
to read in the read callback, since it has no way to distinguish between empty and non-empty
payloads. furthermore, it means that if the module did that, it must never change it, since it'll
break compatibility with it's old RDB files, so this is really not a valid use case.
Since some modules (ones who currently save one field indicating an empty payload), need
to know if saving an empty payload is valid, and if Redis is gonna ignore an empty payload
or store it, we opted to add a new API (rather than change behavior of an existing API and
expect modules to check the redis version)
### Technical Details
To avoid saving AUX data on RDB, we change the code to first save the AUX metadata
(moduleid, when, ...) into a temporary buffer. The buffer is then flushed to the rio at the first
time the module makes a write operation inside the `aux_save` function. If the module saves
nothing (and `aux_save2` was used), the entire temporary buffer is simply dropped and no
data about this AUX field is saved to the RDB. This make it possible to load the RDB even in
the absence of the module.
Test was added to verify the fix.
Motivation: for applications that use RM ACL verification functions, they would
want to return errors back to the user, in ways that are consistent with Redis.
While investigating how we should return ACL errors to the user, we realized that
Redis isn't consistent, and currently returns ACL error strings in 3 primary ways.
[For the actual implications of this change, see the "Impact" section at the bottom]
1. how it returns an error when calling a command normally
ACL_DENIED_CMD -> "this user has no permissions to run the '%s' command"
ACL_DENIED_KEY -> "this user has no permissions to access one of the keys used as arguments"
ACL_DENIED_CHANNEL -> "this user has no permissions to access one of the channels used as arguments"
2. how it returns an error when calling via 'acl dryrun' command
ACL_DENIED_CMD -> "This user has no permissions to run the '%s' command"
ACL_DENIED_KEY -> "This user has no permissions to access the '%s' key"
ACL_DENIED_CHANNEL -> "This user has no permissions to access the '%s' channel"
3. how it returns an error via RM_Call (and scripting is similar).
ACL_DENIED_CMD -> "can't run this command or subcommand";
ACL_DENIED_KEY -> "can't access at least one of the keys mentioned in the command arguments";
ACL_DENIED_CHANNEL -> "can't publish to the channel mentioned in the command";
In addition, if one wants to use RM_Call's "dry run" capability instead of the RM ACL
functions directly, one also sees a different problem than it returns ACL errors with a -ERR,
not a -PERM, so it can't be returned directly to the caller.
This PR modifies the code to generate a base message in a common manner with the ability
to set verbose flag for acl dry run errors, and keep it unset for normal/rm_call/script cases
```c
sds getAclErrorMessage(int acl_res, user *user, struct redisCommand *cmd, sds errored_val, int verbose) {
switch (acl_res) {
case ACL_DENIED_CMD:
return sdscatfmt(sdsempty(), "User %S has no permissions to run "
"the '%S' command", user->name, cmd->fullname);
case ACL_DENIED_KEY:
if (verbose) {
return sdscatfmt(sdsempty(), "User %S has no permissions to access "
"the '%S' key", user->name, errored_val);
} else {
return sdsnew("No permissions to access a key");
}
case ACL_DENIED_CHANNEL:
if (verbose) {
return sdscatfmt(sdsempty(), "User %S has no permissions to access "
"the '%S' channel", user->name, errored_val);
} else {
return sdsnew("No permissions to access a channel");
}
}
```
The caller can append/prepend the message (adding NOPERM for normal/RM_Call or indicating it's within a script).
Impact:
- Plain commands, as well as scripts and RM_Call now include the user name.
- ACL DRYRUN remains the only one that's verbose (mentions the offending channel or key name)
- Changes RM_Call ACL errors from being a `-ERR` to being `-NOPERM` (besides for textual changes)
**This somewhat a breaking change, but it only affects the RM_Call with both `C` and `E`, or `D`**
- Changes ACL errors in scripts textually from being
`The user executing the script <old non unified text>`
to
`ACL failure in script: <new unified text>`
As discussed on #11084, `propagatePendingCommands` should happened after the del
notification is fired so that the notification effect and the `del` will be replicated inside MULTI EXEC.
Test was added to verify the fix.
PR #9320 introduces initialization order changes. Now cluster is initialized after modules.
This changes causes a crash if the module uses RM_Call inside the load function
on cluster mode (the code will try to access `server.cluster` which at this point is NULL).
To solve it, separate cluster initialization into 2 phases:
1. Structure initialization that happened before the modules initialization
2. Listener initialization that happened after.
Test was added to verify the fix.
As mentioned on docs, `RM_ResetDataset` Performs similar operation to FLUSHALL.
As FLUSHALL do not clean the function, `RM_ResetDataset` should not clean the functions
as well.
The original idea behind auto-setting the default (first,last,step) spec was to use
the most "open" flags when the user didn't provide any key-spec flags information.
While the above idea is a good approach, it really makes no sense to set
CMD_KEY_VARIABLE_FLAGS if the user didn't provide the getkeys-api flag:
in this case there's not way to retrieve these variable flags, so what's the point?
Internally in redis there was code to ignore this already, so this fix doesn't change
redis's behavior, it only affects the output of COMMAND command.
If a command gets an OOM response and then if we set maxmemory to zero
to disable the limit, server.pre_command_oom_state never gets updated
and it stays true. As RM_Call() calls with "respect deny-oom" flag checks
server.pre_command_oom_state, all calls will fail with OOM.
Added server.maxmemory check in RM_Call() to process deny-oom flag
only if maxmemory is configured.
Adds a number of user management/ACL validaiton/command execution functions to improve a
Redis module's ability to enforce ACLs correctly and easily.
* RM_SetContextUser - sets a RedisModuleUser on the context, which RM_Call will use to both
validate ACLs (if requested and set) as well as assign to the client so that scripts executed via
RM_Call will have proper ACL validation.
* RM_SetModuleUserACLString - Enables one to pass an entire ACL string, not just a single OP
and have it applied to the user
* RM_GetModuleUserACLString - returns a stringified version of the user's ACL (same format as dump
and list). Contains an optimization to cache the stringified version until the underlying ACL is modified.
* Slightly re-purpose the "C" flag to RM_Call from just being about ACL check before calling the
command, to actually running the command with the right user, so that it also affects commands
inside EVAL scripts. see #11231
When using `INFO ALL <section>`, when `section` is a specific module section.
Redis will not print the additional section(s).
The fix in this case, will search the modules info sections if the user provided additional sections to `ALL`.
Co-authored-by: Oran Agra <oran@redislabs.com>
Add a new "D" flag to RM_Call which runs whatever verification the user requests,
but returns before the actual execution of the command.
It automatically enables returning error messages as CallReply objects to distinguish
success (NULL) from failure (CallReply returned).
When RM_Call was used with `M` (reject OOM), `W` (reject writes),
as well as `S` (rejecting stale or write commands in "Script mode"),
it would have only checked the command flags, but not the declared
script flag in case it's a command that runs a script.
Refactoring: extracts out similar code in server.c's processCommand
to be usable in RM_Call as well.
The PR reverts the changes made on #10969.
The reason for revert was trigger because of occasional test failure
that started after the PR was merged.
The issue is that if there is a lazy expire during the command invocation,
the `del` command is added to the replication stream after the command
placeholder. So the logical order on the primary is:
* Delete the key (lazy expiration)
* Command invocation
But the replication stream gets it the other way around:
* Command invocation (because the command is written into the placeholder)
* Delete the key (lazy expiration)
So if the command write to the key that was just lazy expired we will get
inconsistency between primary and replica.
One solution we considered is to add another lazy expire replication stream
and write all the lazy expire there. Then when replicating, we will replicate the
lazy expire replication stream first. This will solve this specific test failure but
we realize that the issues does not ends here and the more we dig the more
problems we find.One of the example we thought about (that can actually
crashes Redis) is as follow:
* User perform SINTERSTORE
* When Redis tries to fetch the second input key it triggers lazy expire
* The lazy expire trigger a module logic that deletes the first input key
* Now Redis hold the robj of the first input key that was actually freed
We believe we took the wrong approach and we will come up with another
PR that solve the problem differently, for now we revert the changes so we
will not have the tests failure.
Notice that not the entire code was revert, some parts of the PR are changes
that we would like to keep. The changes that **was** reverted are:
* Saving a placeholder for replication at the beginning of the command (`call` function)
* Order of the replication stream on active expire and eviction (we will decide how
to handle it correctly on follow up PR)
* `Spop` changes are no longer needed (because we reverted the placeholder code)
Changes that **was not** reverted:
* On expire/eviction, wrap the `del` and the notification effect in a multi exec.
* `PropagateNow` function can still accept a special dbid, -1, indicating not to replicate select.
* Keep optimisation for reusing the `alsoPropagate` array instead of allocating it each time.
Tests:
* All tests was kept and only few tests was modify to work correctly with the changes
* Test was added to verify that the revert fixes the issues.
* Support BUILD_TLS=module to be loaded as a module via config file or
command line. e.g. redis-server --loadmodule redis-tls.so
* Updates to redismodule.h to allow it to be used side by side with
server.h by defining REDISMODULE_CORE_MODULE
* Changes to server.h, redismodule.h and module.c to avoid repeated
type declarations (gcc 4.8 doesn't like these)
* Add a mechanism for non-ABI neutral modules (ones who include
server.h) to refuse loading if they detect not being built together with
redis (release.c)
* Fix wrong signature of RedisModuleDefragFunc, this could break
compilation of a module, but not the ABI
* Move initialization of listeners in server.c to be after loading
the modules
* Config TLS after initialization of listeners
* Init cluster after initialization of listeners
* Add TLS module to CI
* Fix a test suite race conditions:
Now that the listeners are initialized later, it's not sufficient to
wait for the PID message in the log, we need to wait for the "Server
Initialized" message.
* Fix issues with moduleconfigs test as a result from start_server
waiting for "Server Initialized"
* Fix issues with modules/infra test as a result of an additional module
present
Notes about Sentinel:
Sentinel can't really rely on the tls module, since it uses hiredis to
initiate connections and depends on OpenSSL (won't be able to use any
other connection modules for that), so it was decided that when TLS is
built as a module, sentinel does not support TLS at all.
This means that it keeps using redis_tls_ctx and redis_tls_client_ctx directly.
Example code of config in redis-tls.so(may be use in the future):
RedisModuleString *tls_cfg = NULL;
void tlsInfo(RedisModuleInfoCtx *ctx, int for_crash_report) {
UNUSED(for_crash_report);
RedisModule_InfoAddSection(ctx, "");
RedisModule_InfoAddFieldLongLong(ctx, "var", 42);
}
int tlsCommand(RedisModuleCtx *ctx, RedisModuleString **argv, int argc)
{
if (argc != 2) return RedisModule_WrongArity(ctx);
return RedisModule_ReplyWithString(ctx, argv[1]);
}
RedisModuleString *getStringConfigCommand(const char *name, void *privdata) {
REDISMODULE_NOT_USED(name);
REDISMODULE_NOT_USED(privdata);
return tls_cfg;
}
int setStringConfigCommand(const char *name, RedisModuleString *new, void *privdata, RedisModuleString **err) {
REDISMODULE_NOT_USED(name);
REDISMODULE_NOT_USED(err);
REDISMODULE_NOT_USED(privdata);
if (tls_cfg) RedisModule_FreeString(NULL, tls_cfg);
RedisModule_RetainString(NULL, new);
tls_cfg = new;
return REDISMODULE_OK;
}
int RedisModule_OnLoad(void *ctx, RedisModuleString **argv, int argc)
{
....
if (RedisModule_CreateCommand(ctx,"tls",tlsCommand,"",0,0,0) == REDISMODULE_ERR)
return REDISMODULE_ERR;
if (RedisModule_RegisterStringConfig(ctx, "cfg", "", REDISMODULE_CONFIG_DEFAULT, getStringConfigCommand, setStringConfigCommand, NULL, NULL) == REDISMODULE_ERR)
return REDISMODULE_ERR;
if (RedisModule_LoadConfigs(ctx) == REDISMODULE_ERR) {
if (tls_cfg) {
RedisModule_FreeString(ctx, tls_cfg);
tls_cfg = NULL;
}
return REDISMODULE_ERR;
}
...
}
Co-authored-by: zhenwei pi <pizhenwei@bytedance.com>
Signed-off-by: zhenwei pi <pizhenwei@bytedance.com>
Currently, we call zfree(cmd->args), but the argument array
needs to be freed recursively (there might be sub-args).
Also fixed memory leaks on cmd->tips and cmd->history.
Fixes#11145
Fix replication inconsistency on modules that uses key space notifications.
### The Problem
In general, key space notifications are invoked after the command logic was
executed (this is not always the case, we will discuss later about specific
command that do not follow this rules). For example, the `set x 1` will trigger
a `set` notification that will be invoked after the `set` logic was performed, so
if the notification logic will try to fetch `x`, it will see the new data that was written.
Consider the scenario on which the notification logic performs some write
commands. for example, the notification logic increase some counter,
`incr x{counter}`, indicating how many times `x` was changed.
The logical order by which the logic was executed is has follow:
```
set x 1
incr x{counter}
```
The issue is that the `set x 1` command is added to the replication buffer
at the end of the command invocation (specifically after the key space
notification logic was invoked and performed the `incr` command).
The replication/aof sees the commands in the wrong order:
```
incr x{counter}
set x 1
```
In this specific example the order is less important.
But if, for example, the notification would have deleted `x` then we would
end up with primary-replica inconsistency.
### The Solution
Put the command that cause the notification in its rightful place. In the
above example, the `set x 1` command logic was executed before the
notification logic, so it should be added to the replication buffer before
the commands that is invoked by the notification logic. To achieve this,
without a major code refactoring, we save a placeholder in the replication
buffer, when finishing invoking the command logic we check if the command
need to be replicated, and if it does, we use the placeholder to add it to the
replication buffer instead of appending it to the end.
To be efficient and not allocating memory on each command to save the
placeholder, the replication buffer array was modified to reuse memory
(instead of allocating it each time we want to replicate commands).
Also, to avoid saving a placeholder when not needed, we do it only for
WRITE or MAY_REPLICATE commands.
#### Additional Fixes
* Expire and Eviction notifications:
* Expire/Eviction logical order was to first perform the Expire/Eviction
and then the notification logic. The replication buffer got this in the
other way around (first notification effect and then the `del` command).
The PR fixes this issue.
* The notification effect and the `del` command was not wrap with
`multi-exec` (if needed). The PR also fix this issue.
* SPOP command:
* On spop, the `spop` notification was fired before the command logic
was executed. The change in this PR would have cause the replication
order to be change (first `spop` command and then notification `logic`)
although the logical order is first the notification logic and then the
`spop` logic. The right fix would have been to move the notification to
be fired after the command was executed (like all the other commands),
but this can be considered a breaking change. To overcome this, the PR
keeps the current behavior and changes the `spop` code to keep the right
logical order when pushing commands to the replication buffer. Another PR
will follow to fix the SPOP properly and match it to the other command (we
split it to 2 separate PR's so it will be easy to cherry-pick this PR to 7.0 if
we chose to).
#### Unhanded Known Limitations
* key miss event:
* On key miss event, if a module performed some write command on the
event (using `RM_Call`), the `dirty` counter would increase and the read
command that cause the key miss event would be replicated to the replication
and aof. This problem can also happened on a write command that open
some keys but eventually decides not to perform any action. We decided
not to handle this problem on this PR because the solution is complex
and will cause additional risks in case we will want to cherry-pick this PR.
We should decide if we want to handle it in future PR's. For now, modules
writers is advice not to perform any write commands on key miss event.
#### Testing
* We already have tests to cover cases where a notification is invoking write
commands that are also added to the replication buffer, the tests was modified
to verify that the replica gets the command in the correct logical order.
* Test was added to verify that `spop` behavior was kept unchanged.
* Test was added to verify key miss event behave as expected.
* Test was added to verify the changes do not break lazy expiration.
#### Additional Changes
* `propagateNow` function can accept a special dbid, -1, indicating not
to replicate `select`. We use this to replicate `multi/exec` on `propagatePendingCommands`
function. The side effect of this change is that now the `select` command
will appear inside the `multi/exec` block on the replication stream (instead of
outside of the `multi/exec` block). Tests was modified to match this new behavior.
A timing issue like this was reported in freebsd daily CI:
```
*** [err]: Sanity test push cmd after resharding in tests/unit/cluster/cli.tcl
Expected 'CLUSTERDOWN The cluster is down' to match '*MOVED*'
```
We additionally wait for each node to reach a consensus on the cluster
state in wait_for_condition to avoid the cluster down error.
The fix just like #10495, quoting madolson's comment:
Cluster check just verifies the the config state is self-consistent,
waiting for cluster_state to be okay is an independent check that all
the nodes actually believe each other are healthy.
At the same time i noticed that unit/moduleapi/cluster.tcl has an exact
same test, may have the same problem, also modified it.
Since the ranges of `unsigned long long` and `long long` are different, we cannot read an
`unsigned long long` integer from a `RedisModuleString` by `RedisModule_StringToLongLong` .
So I added two new Redis Module APIs to support the conversion between these two types:
* `RedisModule_StringToULongLong`
* `RedisModule_CreateStringFromULongLong`
Signed-off-by: RinChanNOWWW <hzy427@gmail.com>
The PR fixes 2 issues:
### RM_Call crash on script mode
`RM_Call` can potentially be called from a background thread where `server.current_client`
are not set. In such case we get a crash on `NULL` dereference.
The fix is to check first if `server.current_client` is `NULL`, if it does we should
verify disc errors and readonly replica as we do to any normal clients (no masters nor AOF).
### RM_Call block OOM commands when not needed
Again `RM_Call` can be executed on a background thread using a `ThreadSafeCtx`.
In such case `server.pre_command_oom_state` can be irrelevant and should not be
considered when check OOM state. This cause OOM commands to be blocked when
not necessarily needed.
In such case, check the actual used memory (and not the cached value). Notice that in
order to know if the cached value can be used, we check that the ctx that was used on
the `RM_Call` is a ThreadSafeCtx. Module writer can potentially abuse the API and use
ThreadSafeCtx on the main thread. We consider this as a API miss used.
The SET and BITFIELD command were added `get_keys_function` in #10148, causing
them to be wrongly marked movablekeys in `populateCommandMovableKeys`.
This was an unintended side effect introduced in #10148 (7.0 RC1)
which could cause some clients an extra round trip for these commands in cluster mode.
Since we define movablekeys as a way to determine if the legacy range [first, last, step]
doesn't find all keys, then we need a completely different approach.
The right approach should be to check if the legacy range covers all key-specs,
and if none of the key-specs have the INCOMPLETE flag.
This way, we don't need to look at getkeys_proc of VARIABLE_FLAG at all.
Probably with the exception of modules, who may still not be using key-specs.
In this PR, we removed `populateCommandMovableKeys` and put its logic in
`populateCommandLegacyRangeSpec`.
In order to properly serve both old and new modules, we must probably keep relying
CMD_MODULE_GETKEYS, but do that only for modules that don't declare key-specs.
For ones that do, we need to take the same approach we take with native redis commands.
This approach was proposed by Oran. Fixes#10833
Co-authored-by: Oran Agra <oran@redislabs.com>
The important part is that read-only scripts (not just EVAL_RO
and FCALL_RO, but also ones with `no-writes` executed by normal EVAL or
FCALL), will now be permitted to run during CLIENT PAUSE WRITE (unlike
before where only the _RO commands would be processed).
Other than that, some errors like OOM, READONLY, MASTERDOWN are now
handled by processCommand, rather than the command itself affects the
error string (and even error code in some cases), and command stats.
Besides that, now the `may-replicate` commands, PFCOUNT and PUBLISH, will
be considered `write` commands in scripts and will be blocked in all
read-only scripts just like other write commands.
They'll also be blocked in EVAL_RO (i.e. even for scripts without the
`no-writes` shebang flag.
This commit also hides the `may_replicate` flag from the COMMAND command
output. this is a **breaking change**.
background about may_replicate:
We don't want to expose a no-may-replicate flag or alike to scripts, since we
consider the may-replicate thing an internal concern of redis, that we may
some day get rid of.
In fact, the may-replicate flag was initially introduced to flag EVAL: since
we didn't know what it's gonna do ahead of execution, before function-flags
existed). PUBLISH and PFCOUNT, both of which because they have side effects
which may some day be fixed differently.
code changes:
The changes in eval.c are mostly code re-ordering:
- evalCalcFunctionName is extracted out of evalGenericCommand
- evalExtractShebangFlags is extracted luaCreateFunction
- evalGetCommandFlags is new code
* Fix broken protocol when redis can't persist to RDB (general commands, not
modules), excessive newline. regression of #10372 (7.0 RC3)
* Fix broken protocol when Redis can't persist to AOF (modules and
scripts), missing newline.
* Fix bug in OOM check of EVAL scripts called from RM_Call.
set the cached OOM state for scripts before executing module commands too,
so that it can serve scripts that are executed by modules.
i.e. in the past EVAL executed by RM_Call could have either falsely
fail or falsely succeeded because of a wrong cached OOM state flag.
* Fix bugs with RM_Yield:
1. SHUTDOWN should only accept the NOSAVE mode
2. Avoid eviction during yield command processing.
3. Avoid processing master client commands while yielding from another client
* Add new two more checks to RM_Call script mode.
1. READONLY You can't write against a read only replica
2. MASTERDOWN Link with MASTER is down and `replica-serve-stale-data` is set to `no`
* Add new RM_Call flag to let redis automatically refuse `deny-oom` commands
while over the memory limit.
* Add tests to cover various errors from Scripts, Modules, Modules
calling scripts, and Modules calling commands in script mode.
Add tests:
* Looks like the MISCONF error was completely uncovered by the tests,
add tests for it, including from scripts, and modules
* Add tests for NOREPLICAS from scripts
* Add tests for the various errors in module RM_Call, including RM_Call that
calls EVAL, and RM_call in "eval mode". that includes:
NOREPLICAS, READONLY, MASTERDOWN, MISCONF
To easily distinguish between sharded channel message and a global
channel message, introducing `smessage` (instead of `message`) as
message bulk for sharded channel publish message.
This is gonna be a breaking change in 7.0.1!
Background:
Sharded pubsub introduced in redis 7.0, but after the release we quickly
realized that the fact that it's problematic that the client can't distinguish
between normal (global) pubsub messages and sharded ones.
This is important because the same connection can subscribe to both,
but messages sent to one pubsub system are not propagated to the
other (they're completely separate), so if one connection is used to
subscribe to both, we need to assist the client library to know which
message it got so it can forward it to the correct callback.
The purpose of the test is to kill the child while it is running.
From the last two lines we can see the child exits before being killed.
```
- Module fork started pid: 56998
* <fork> fork child started
- Killing running module fork child: 56998
* <fork> fork child exiting
signal-handler (1652267501) Received SIGUSR1 in child, exiting now.
```
In this commit, we pass an argument to `fork.create` indicating how
long it should sleep. For the fork kill test, we use a longer time to
avoid the child exiting before being killed.
Other changes:
use wait_for_condition instead of hardcoded `after 250`.
Unify the test for failing fork with the one for killing it (save time)
If we want to support bits that can be overlapping, we need to make sure
that:
1. we don't use the same bit for two return values.
2. values should be sorted so that prefer ones (matching more
bits) come first.
Enables registration of an enum config that'll let the user pass multiple keywords that
will be combined with `|` as flags into the integer config value.
```
const char *enum_vals[] = {"none", "one", "two", "three"};
const int int_vals[] = {0, 1, 2, 4};
if (RedisModule_RegisterEnumConfig(ctx, "flags", 3, REDISMODULE_CONFIG_DEFAULT | REDISMODULE_CONFIG_BITFLAGS, enum_vals, int_vals, 4, getFlagsConfigCommand, setFlagsConfigCommand, NULL, NULL) == REDISMODULE_ERR) {
return REDISMODULE_ERR;
}
```
doing:
`config set moduleconfigs.flags "two three"` will result in 6 being passed to`setFlagsConfigCommand`.
The SHUTDOWN command has various flags to change it's default behavior,
but in some cases establishing a connection to redis is complicated and it's easier
for the management software to use signals. however, so far the signals could only
trigger the default shutdown behavior.
Here we introduce the option to control shutdown arguments for SIGTERM and SIGINT.
New config options:
`shutdown-on-sigint [nosave | save] [now] [force]`
`shutdown-on-sigterm [nosave | save] [now] [force]`
Implementation:
Support MULTI_ARG_CONFIG on createEnumConfig to support multiple enums to be applied as bit flags.
Co-authored-by: Oran Agra <oran@redislabs.com>
Adds the `allow-cross-slot-keys` flag to Eval scripts and Functions to allow
scripts to access keys from multiple slots.
The default behavior is now that they are not allowed to do that (unlike before).
This is a breaking change for 7.0 release candidates (to be part of 7.0.0), but
not for previous redis releases since EVAL without shebang isn't doing this check.
Note that the check is done on both the keys declared by the EVAL / FCALL command
arguments, and also the ones used by the script when making a `redis.call`.
A note about the implementation, there seems to have been some confusion
about allowing access to non local keys. I thought I missed something in our
wider conversation, but Redis scripts do block access to non-local keys.
So the issue was just about cross slots being accessed.
1. Disk error and slave count checks didn't flag the transactions or counted correctly in command stats (regression from #10372 , 7.0 RC3)
2. RM_Call will reply the same way Redis does, in case of non-exisitng command or arity error
3. RM_WrongArtiy will consider the full command name
4. Use lowercase 'u' in "unknonw subcommand" (to align with "unknown command")
Followup work of #10127
