Diskless master has some inherent latencies.
1) fork starts with delay from cron rather than immediately
2) replica is put online only after an ACK. but the ACK
was sent only once a second.
3) but even if it would arrive immediately, it will not
register in case cron didn't yet detect that the fork is done.
Besides that, when a replica disconnects, it doesn't immediately
attempts to re-connect, it waits for replication cron (one per second).
in case it was already online, it may be important to try to re-connect
as soon as possible, so that the backlog at the master doesn't vanish.
In case it disconnected during rdb transfer, one can argue that it's
not very important to re-connect immediately, but this is needed for the
"diskless loading short read" test to be able to run 100 iterations in 5
seconds, rather than 3 (waiting for replication cron re-connection)
changes in this commit:
1) sync command starts a fork immediately if no sync_delay is configured
2) replica sends REPLCONF ACK when done reading the rdb (rather than on 1s cron)
3) when a replica unexpectedly disconnets, it immediately tries to
re-connect rather than waiting 1s
4) when when a child exits, if there is another replica waiting, we spawn a new
one right away, instead of waiting for 1s replicationCron.
5) added a call to connectWithMaster from replicationSetMaster. which is called
from the REPLICAOF command but also in 3 places in cluster.c, in all of
these the connection attempt will now be immediate instead of delayed by 1
second.
side note:
we can add a call to rdbPipeReadHandler in replconfCommand when getting
a REPLCONF ACK from the replica to solve a race where the replica got
the entire rdb and EOF marker before we detected that the pipe was
closed.
in the test i did see this race happens in one about of some 300 runs,
but i concluded that this race is unlikely in real life (where the
replica is on another host and we're more likely to first detect the
pipe was closed.
the test runs 100 iterations in 3 seconds, so in some cases it'll take 4
seconds instead (waiting for another REPLCONF ACK).
Removing unneeded startBgsaveForReplication from updateSlavesWaitingForBgsave
Now that CheckChildrenDone is calling the new replicationStartPendingFork
(extracted from serverCron) there's actually no need to call
startBgsaveForReplication from updateSlavesWaitingForBgsave anymore,
since as soon as updateSlavesWaitingForBgsave returns, CheckChildrenDone is
calling replicationStartPendingFork that handles that anyway.
The code in updateSlavesWaitingForBgsave had a bug in which it ignored
repl-diskless-sync-delay, but removing that code shows that this bug was
hiding another bug, which is that the max_idle should have used >= and
not >, this one second delay has a big impact on my new test.
this race would only happen when two threads paniced at the same time,
and even then the only consequence is some extra log lines.
race reported in #7391
This makes it possible to add tests that generate assertions, and run
them with valgrind, making sure that there are no memory violations
prior to the assertion.
New config options:
- crash-log-enabled - can be disabled for cleaner core dumps
- crash-memcheck-enabled - useful for faster termination after a crash
- use-exit-on-panic - to be used by the test suite so that valgrind can
detect leaks and memory corruptions
Other changes:
- Crash log is printed even on system that dont HAVE_BACKTRACE, i.e. in
both SIGSEGV and assert / panic
- Assertion and panic won't print registers and code around EIP (which
was useless), but will do fast memory test (which may still indicate
that the assertion was due to memory corrpution)
I had to reshuffle code in order to re-use it, so i extracted come code
into function without actually doing any changes to the code:
- logServerInfo
- logModulesInfo
- doFastMemoryTest (with the exception of it being conditional)
- dumpCodeAroundEIP
changes to the crash report on segfault:
- logRegisters is called right after the stack trace (before info) done
just in order to have more re-usable code
- stack trace skips the first two items on the stack (the crash log and
signal handler functions)
Syntax: `ZMSCORE KEY MEMBER [MEMBER ...]`
This is an extension of #2359
amended by Tyson Andre to work with the changed unstable API,
add more tests, and consistently return an array.
- It seemed as if it would be more likely to get reviewed
after updating the implementation.
Currently, multi commands or lua scripting to call zscore multiple times
would almost definitely be less efficient than a native ZMSCORE
for the following reasons:
- Need to fetch the set from the string every time instead of reusing the C
pointer.
- Using pipelining or multi-commands would result in more bytes sent by
the client for the repeated `ZMSCORE KEY` sections.
- Need to specially encode the data and decode it from the client
for lua-based solutions.
- The fastest solution I've seen for large sets(thousands or millions)
involves lua and a variadic ZADD, then a ZINTERSECT, then a ZRANGE 0 -1,
then UNLINK of a temporary set (or lua). This is still inefficient.
Co-authored-by: Tyson Andre <tysonandre775@hotmail.com>
The Redis sentinel would crash with a segfault after a few minutes
because it tried to read from a page without read permissions. Check up
front whether the sds is long enough to contain redis:slave or
redis:master before memcmp() as is done everywhere else in
sentinelRefreshInstanceInfo().
Bug report and commit message from Theo Buehler. Fix from Nam Nguyen.
Co-authored-by: Nam Nguyen <namn@berkeley.edu>
valsize was not modified during the for loop below instead of getting from c->argv[4], therefore there is no need to put inside the for loop.. Moreover, putting the check outside loop will also avoid memory leaking, decrRefCount(key) should be called in the original code if we put the check in for loop
The connection API may create an accepted connection object in an error
state, and callers are expected to check it before attempting to use it.
Co-authored-by: mrpre <mrpre@163.com>
- the test now waits for specific set of log messages rather than wait for
timeout looking for just one message.
- we don't wanna sample the current length of the log after an action, due
to a race, we need to start the search from the line number of the last
message we where waiting for.
- when attempting to trigger a full sync, use multi-exec to avoid a race
where the replica manages to re-connect before we completed the set of
actions that should force a full sync.
- fix verify_log_message which was broken and unused
Initialize and configure OpenSSL even when tls-port is not used, because
we may still have tls-cluster or tls-replication.
Also, make sure to reconfigure OpenSSL when these parameters are changed
as TLS could have been enabled for the first time.
Initialize and configure OpenSSL even when tls-port is not used, because
we may still have tls-cluster or tls-replication.
Also, make sure to reconfigure OpenSSL when these parameters are changed
as TLS could have been enabled for the first time.
on ci.redis.io the test fails a lot, reporting that bgsave didn't end.
increaseing the timeout we wait for that bgsave to get aborted.
in addition to that, i also verify that it indeed got aborted by
checking that the save counter wasn't reset.
add another test to verify that a successful bgsave indeed resets the
change counter.
this code is in use only if the master is disk-based, and the replica is
diskless. In this case we use a buffered reader, but we must avoid reading
past the rdb file, into the command stream. which Luckly rdb.c doesn't
really attempt to do (it knows how much it should read).
When rioConnRead detects that the extra buffering attempt reaches beyond
the read limit it should read less, but if the caller actually requested
more, then it should return with an error rather than a short read. the
bug would have resulted in short read.
in order to fix it, the code must consider the real requested size, and
not the extra buffering size.
in cases where you have
test name {
start_server {
start_server {
assert
}
}
}
the exception will be thrown to the test proc, and the servers are
supposed to be killed on the way out. but it seems there was always a
bug of not cleaning the server stack, and recently (#7404) we started
relying on that stack in order to kill them, so with that bug sometimes
we would have tried to kill the same server twice, and leave one alive.
luckly, in most cases the pattern is:
start_server {
test name {
}
}
This re-implements the redis-cli --pipe test so it no longer depends on a close feature available only in TCL 8.6.
Basically what this test does is run redis-cli --pipe, generates a bunch of commands and pipes them through redis-cli, and inspects the result in both Redis and the redis-cli output.
To do that, we need to close stdin for redis-cli to indicate we're done so it can flush its buffers and exit. TCL has bi-directional channels can only offers a way to "one-way close" a channel with TCL 8.6. To work around that, we now generate the commands into a file and feed that file to redis-cli directly.
As we're writing to an actual file, the number of commands is now reduced.
Before that PR, processCommand() did not notice that cmd could be a module
command in which case getkeys_proc member has a different meaning.
The outcome was that a module command which doesn't take any key names in its
arguments (similar to SLOWLOG) would be handled as if it might have key name arguments
(similar to MEMORY), would consider cluster redirect but will end up with 0 keys
after an excessive call to getKeysFromCommand, and eventually do the right thing.
