This is a light-weight replace function, useful for use cases such as
realloc()ing an existing value, etc. Using RM_ModuleTypeSetValue() in
such cases is wasteful and complex as it attempts to delete the old
value, call its destructor, etc.
Calling XADD with 0-0 or 0 would result in creating an
empty key and storing it in the database.
Even worse, because XADD will reply with error the action
will not be replicated, creating a master-replica
inconsistency
Reduce default minimum effort, so that when fragmentation is just detected,
the impact on the latency will be minor.
Reduce the default maximum effort, mainly to prevent a case were a sudden
massive deletions, won't trigger an aggressive defrag that will cause latency.
When activedefrag is disabled mid-run, reset the 'running' info field, and
clear the scan cursor, so that when it'll be re-enabled, a new fresh scan will
start.
Clearing the 'running' variable is important since lowering the defragger
tunables mid-scan won't help, the defragger only considers new threshold when
a new scan starts, and during a scan it can only become more aggressive,
(when more severe fragmentation is detected), it'll never go less aggressive.
So by temporarily disabling activedefrag, one can lower th the tunables.
Removing the experimantal warning.
- Adding RM_ScanKey
- Adding tests for RM_ScanKey
- Refactoring RM_Scan API
Changes in RM_Scan
- cleanup in docs and coding convention
- Moving out of experimantal Api
- Adding ctx to scan callback
- Dont use cursor of -1 as an indication of done (can be a valid cursor)
- Set errno when returning 0 for various reasons
- Rename Cursor to ScanCursor
- Test filters key that are not strings, and opens a key if NULL
The implementation expose the following new functions:
1. RedisModule_CursorCreate - allow to create a new cursor object for
keys scanning
2. RedisModule_CursorRestart - restart an existing cursor to restart the
scan
3. RedisModule_CursorDestroy - destroy an existing cursor
4. RedisModule_Scan - scan keys
The RedisModule_Scan function gets a cursor object, a callback and void*
(used as user private data).
The callback will be called for each key in the database proving the key
name and the value as RedisModuleKey.
- the API name was odd, separated to two apis one for LRU and one for LFU
- the LRU idle time was in 1 second resolution, which might be ok for RDB
and RESTORE, but i think modules may need higher resolution
- adding tests for LFU and for handling maxmemory policy mismatch
Fixes GitHub issue #6492
Added stream support in RM_KeyType and RM_ValueLength.
Also moduleDelKeyIfEmpty was updated, even though it has
no effect now (It will be relevant when stream type direct
API will be coded - i.e. RM_StreamAdd)
The exposed functions:
1. RedisModule_GetUsedMemoryPercentage - return the used memory
2. RedisModue_MallocSize - return for a given pointer, the amount of memory allocated for this pointer
One problem with the solution proposed so far in #6537 is that key
lookups outside a command execution via call(), still used a cached
time. The cached time needed to be refreshed in multiple places,
especially because of modules callbacks from timers, cluster bus, and
thread safe contexts, that may use RM_Open().
In order to avoid this problem, this commit introduces the ability to
detect if we are inside call(): this way we can use the reference fixed
time only when we are in the context of a command execution or Lua
script, but for the asynchronous lookups, we can still use mstime() to
get a fresh time reference.
After the thread in #6537 and thanks to the suggestions received, this
commit updates the original patch in order to:
1. Solve the problem of updating the time in multiple places by updating
it in call().
2. Avoid introducing a new field but use our cached time.
This required some minor refactoring to the function updating the time,
and the introduction of a new cached time in microseconds in order to
use less gettimeofday() calls.
Calling lookupKey*() many times to search a key in one command
may get different result.
That's because lookupKey*() calls expireIfNeeded(), and delete
the key when reach the expire time. So we can get an robj before
the expire time, but a NULL after the expire time.
The worst is that may lead to Redis crash, for example
`RPOPLPUSH foo foo` the first time we get a list form `foo` and
hold the pointer, but when we get `foo` again it's expired and
deleted. Now we hold a freed memory, when execute rpoplpushHandlePush()
redis crash.
To fix it, we can refactor the judgment about whether a key is expired,
using the same basetime `server.cmd_start_mstime` instead of calling
mstime() everytime.
Add two new functions that leverage the RedisModuleDataType mechanism
for RDB serialization/deserialization and make it possible to use it
to/from arbitrary strings:
* RM_SaveDataTypeToString()
* RM_LoadDataTypeFromString()
rename RM_ServerInfoGetFieldNumerical RM_ServerInfoGetFieldSigned
move string2ull to util.c
fix leak in RM_GetServerInfo when duplicate info fields exist
looks like each platform implements long double differently (different bit count)
so we can't save them as binary, and we also want to avoid creating a new RDB
format version, so we save these are hex strings using "%La".
This commit includes a change in the arguments of ld2string to support this.
as well as tests for coverage and short reads.
coded by @guybe7
- Add RM_GetServerInfo and friends
- Add auto memory for new opaque struct
- Add tests for new APIs
other minor fixes:
- add const in various char pointers
- requested_section in modulesCollectInfo was actually not sds but char*
- extract new string2d out of getDoubleFromObject for code reuse
Add module API for
See #6525, this likely creates a NULL deference if the client was
terminated by Redis between the creation of the blocked client and the
creation of the thread safe context.
Using the is_key_ready() callback plus the reply callback later, creates
different issues AFAIK:
1. More complex API.
2. We need to call the reply callback() ASAP if the is_key_ready()
interface returned success, however the internals do not work in that
way, so when the reply callback is called the setup could be different.
To fix that, there is to break the current design that handles the
unblocked clients asyncrhonously, and run the list ASAP.
* replication hooks: role change, master link status, replica online/offline
* persistence hooks: saving, loading, loading progress
* misc hooks: cron loop, shutdown, module loaded/unloaded
* change the way hooks test work, and add tests for all of the above
startLoading() now gets flag indicating what is loaded.
stopLoading() now gets an indication of success or failure.
adding startSaving() and stopSaving() with similar args and role.
Some commands would want to open a key without touching it's LRU/LFU
similarly to the OBJECT or DEBUG command do.
Other commands may want to implement logic similar to what RESTORE
does (and in the future MIGRATE) and get/set the LRU or LFU.
Adding a test for coverage for RM_Call in a new "misc" unit
to be used for various short simple tests
also solves compilation warnings in redismodule.h and fork.c
As we know if a module exports module-side data types,
unload it is not allowed. This rule is the same with
blocked clients in module, because we use background
threads to implement module blocked clients, and it's
not safe to unload a module if there are background
threads running. So it's necessary to check if any
blocked clients running in this module when unload it.
Moreover, after that we can ensure that if no modules,
then no module blocked clients even module unloaded.
So, we can call moduleHandleBlockedClients only when
we have installed modules.
Calling a module hook callback may result in callback operations in turn
triggering other events the module is subscribed too. We don't want to
trigger those, it's unsafe and quite confusing, and to do it correcly we
would need to maintain an event list: quite a more complex
implementation.
This is what happened:
1. Instance starts, is a slave in the cluster configuration, but
actually server.masterhost is not set, so technically the instance
is acting like a master.
2. loadDataFromDisk() calls replicationCacheMasterUsingMyself() even if
the instance is a master, in the case it is logically a slave and the
cluster is enabled. So now we have a cached master even if the instance
is practically configured as a master (from the POV of
server.masterhost value and so forth).
3. clusterCron() sees that the instance requires to replicate from its
master, because logically it is a slave, so it calls
replicationSetMaster() that will in turn call
replicationCacheMasterUsingMyself(): before this commit, this call would
overwrite the old cached master, creating a memory leak.
This adds support for explicit configuration of a CA certs directory (in
addition to the previously supported bundle file). For redis-cli, if no
explicit CA configuration is supplied the system-wide default
configuration will be adopted.
misc:
- handle SSL_has_pending by iterating though these in beforeSleep, and setting timeout of 0 to aeProcessEvents
- fix issue with epoll signaling EPOLLHUP and EPOLLERR only to the write handlers. (needed to detect the rdb pipe was closed)
- add key-load-delay config for testing
- trim connShutdown which is no longer needed
- rioFdsetWrite -> rioFdWrite - simplified since there's no longer need to write to multiple FDs
- don't detect rdb child exited (don't call wait3) until we detect the pipe is closed
- Cleanup bad optimization from rio.c, add another one
* Introduce a connection abstraction layer for all socket operations and
integrate it across the code base.
* Provide an optional TLS connections implementation based on OpenSSL.
* Pull a newer version of hiredis with TLS support.
* Tests, redis-cli updates for TLS support.
cluster.c - stack buffer memory alignment
The pointer 'buf' is cast to a more strictly aligned pointer type
evict.c - lazyfree_lazy_eviction, lazyfree_lazy_eviction always called
defrag.c - bug in dead code
server.c - casting was missing parenthesis
rax.c - indentation / newline suggested an 'else if' was intended
It seeems that since I added the creation of the jemalloc thread redis
sometimes fails to start with the following error:
Inconsistency detected by ld.so: dl-tls.c: 493: _dl_allocate_tls_init: Assertion `listp->slotinfo[cnt].gen <= GL(dl_tls_generation)' failed!
This seems to be due to a race bug in ld.so, in which TLS creation on the
thread, collide with dlopen.
Move the creation of BIO and jemalloc threads to after modules are loaded.
plus small bugfix when trying to disable the jemalloc thread at runtime
since the slowlog and other means that can help you detect the bad script
are only exposed after the script is done. it might be a good idea to at least
print the script name (sha) to the log when it timeouts.
The correct way to access the module about a given IO context is to
deference io->type->module, since io->ctx is only populated if the user
requests an explicit context from an IO object.
We don't want that the API could be used directly in an unsafe way,
without checking if there is an active child. Now the safety checks are
moved directly in the function performing the operations.
In theory currently there is only one active child, but the API may
change or for bugs in the implementation we may have several (it was
like that for years because of a bug). Better to wait for a specific
pid and avoid consuing other pending children information.
We can't expect SIGUSR1 to have any specific value range, so let's
define an exit code that we can handle in a special way.
This also fixes an #include <wait.h> that is not standard.
SipHash expects a 128-bit key, and we were indeed generating 128-bits,
but restricting them to hex characters 0-9a-f, effectively giving us
only 4 bits-per-byte of key material, and 64 bits overall.
Now, we skip the hex conversion and supply 128 bits of unfiltered
random data.
Here we introduce a change in the way we convert values from Lua to
Redis when RESP3 is selected: this is possible without breaking the fact
we can return directly what a command returned, because there is no
Redis command in RESP2 that returns true or false to Lua, so the
conversion in the case of RESP2 is totally arbitrary. When a script is
written selecting RESP3 from Lua, it totally makes sense to change such
behavior and return RESP3 true/false when Lua true/false is returned.
We want all the scripts to run in RESP2 mode by default. It's up to the
caller to switch to V3 using redis.setresp() if it is really needed.
This way most scripts written for past Redis versions will continue to
work with Redis >= 6 even if the client is in RESP3 mode.
Note that this breaks API compatibility with Redis < 6:
CONFIG GET requirepass
Will no longer return a cleartext password as well, but the SHA256 hash
of the password set.
When implementing the code that saves and loads these aux fields we used rdb
format that was added for that in redis 5.0, but then we added the 'when' field
which meant that the old redis-check-rdb won't be able to skip these.
this fix adds an opcode as if that 'when' is part of the module data.
Before this commit we may have not consumer buffers when a read error is
encountered. Such buffers may contain errors that are important clues
for the user: for instance a protocol error in the payload we send in
pipe mode will cause the server to abort the connection. If the user
does not get the protocol error, debugging what is happening can be a
nightmare.
This commit fixes issue #3756.
of aarch64.
The content comes from the definition of the sigcontext and tested on
my aarch64 server.
sigcontext defined at the linux kernel code:
arch/arm64/include/uapi/asm/sigcontext.h
This is extremely useful in order to simulate an high load of requests
about different keys, and force Redis to track a lot of informations
about several clients, to simulate real world workloads.
Now that the call also invalidates client side caching slots, it is
important that after an internal flush operation we both send the
notifications to the clients and, at the same time, are able to reclaim
the memory of the tracking table. This may even fix a few edge cases
related to MULTI/EXEC + WATCH during resync, not sure, but in general
looks more correct.
Otherwise what happens is that the tracking table will never get garbage
collected if there are no longer clients with tracking enabled.
Now the invalidation function immediately checks if there is any table
allocated, otherwise it returns ASAP, so the overhead when the feature
is not used should be near zero.
This is especially needed in diskless loading, were a short read could have
caused redis to exit. now the module can handle the error and return to the
caller gracefully.
this fixes#5326
Without such change, the diskless replicas, when loading RDB files from
the socket will not abort when a broken RDB file gets loaded. This is
potentially unsafe, because right now Redis is not able to guarantee
that encoding errors are safe from the POV of memory corruptions (for
instance the LZF library may not be safe against untrusted data?) so
better to abort when the RDB file we are going to load is corrupted.
Instead I/O errors are still returned to the caller without aborting,
so that in case of short read the diskless replica can try again.
now that replica can read rdb directly from the socket, it should avoid exiting
on short read and instead try to re-sync.
this commit tries to have minimal effects on non-diskless rdb reading.
and includes a test that tries to trigger this scenario on various read cases.
* create module API for forking child processes.
* refactor duplicate code around creating and tracking forks by AOF and RDB.
* child processes listen to SIGUSR1 and dies exitFromChild in order to
eliminate a valgrind warning of unhandled signal.
* note that BGSAVE error reply has changed.
valgrind error is:
Process terminating with default action of signal 10 (SIGUSR1)
The implementation of the diskless replication was currently diskless only on the master side.
The slave side was still storing the received rdb file to the disk before loading it back in and parsing it.
This commit adds two modes to load rdb directly from socket:
1) when-empty
2) using "swapdb"
the third mode of using diskless slave by flushdb is risky and currently not included.
other changes:
--------------
distinguish between aof configuration and state so that we can re-enable aof only when sync eventually
succeeds (and not when exiting from readSyncBulkPayload after a failed attempt)
also a CONFIG GET and INFO during rdb loading would have lied
When loading rdb from the network, don't kill the server on short read (that can be a network error)
Fix rdb check when performed on preamble AOF
tests:
run replication tests for diskless slave too
make replication test a bit more aggressive
Add test for diskless load swapdb
