This PR not only fixes the problem that swapdb does not make the
transaction fail, but also optimizes the FLUSHALL and FLUSHDB command to
set the CLIENT_DIRTY_CAS flag to avoid unnecessary traversal of clients.
FLUSHDB was changed to first iterate on all watched keys, and then on the
clients watching each key.
Instead of iterating though all clients, and for each iterate on watched keys.
Co-authored-by: Oran Agra <oran@redislabs.com>
(cherry picked from commit f571f8467cecb69a1c7c6810a445addfb802d85a)
Older arm64 Linux kernels have a bug that could lead to data corruption during
background save under the following scenario:
1) jemalloc uses MADV_FREE on a page,
2) jemalloc reuses and writes the page,
3) Redis forks the background save process, and
4) Linux performs page reclamation.
Under these conditions, Linux will reclaim the page wrongfully and the
background save process will read zeros when it tries to read the page.
The bug has been fixed in Linux with commit:
ff1712f953e27f0b0718762ec17d0adb15c9fd0b ("arm64: pgtable: Ensure dirty bit is
preserved across pte_wrprotect()")
This Commit adds an ignore-warnings config, when not found, redis will
print a warning and exit on startup (default behavior).
Co-authored-by: Oran Agra <oran@redislabs.com>
(cherry picked from commit 75bbf56d37d1134cc9c4f36900a4a623604776a5)
in 6.0 this warning is ignored by default in order to avoid adding
regression, specifically for deployments that don't need persistence or
replication
When replica diskless-load type is swapdb in cluster mode, we didn't backup
keys to slots map, so we will lose keys to slots map if fail to sync.
Now we backup keys to slots map at first, and restore it properly when fail.
This commit includes a refactory/cleanup of the backups mechanism (moving it to db.c and re-structuring it a bit).
Co-authored-by: Oran Agra <oran@redislabs.com>
(cherry picked from commit 10712afaf3e7f2ea859622fa5b27c96ee8f478c5)
Fix: When oom-score-adj-values is provided in the config file after
oom-score-adj yes, it'll take an immediate action, before
readOOMScoreAdj was acquired, resulting in an error (out of range score
due to uninitialized value. delay the reaction the real call is made by
main().
Since the values are clamped to -1000..1000, and they're
applied as an offset from the value at startup (which may be -1000), we
need to allow the offsets to reach to +2000 so that a value of +1000 is
achievable in case the value at startup was -1000.
Adding an option for absolute values rather than relative ones.
(cherry picked from commit f08fd95c6686467ecd46116dab150d47563aed1c)
The bug was introduced by #5021 which only attempted avoid EXIST on an
already expired key from returning 1 on a replica.
Before that commit, dbExists was used instead of
lookupKeyRead (which had an undesired effect to "touch" the LRU/LFU)
Other than that, this commit fixes OBJECT to also come empty handed on
expired keys in replica.
And DEBUG DIGEST-VALUE to behave like DEBUG OBJECT (get the data from
the key regardless of it's expired state)
(cherry picked from commit 168dcb549c3d5253fc69d6150ce98f8eb9ca0c99)
Avoid using a static buffer for short key index responses, and make it
caller's responsibility to stack-allocate a result type. Responses that
don't fit are still allocated on the heap.
(cherry picked from commit bf5beab64a196214c3c741d9ef67d0446c6480c3)
track and report memory used by clients argv.
this is very usaful in case clients started sending a command and didn't
complete it. in which case the first args of the command are already
trimmed from the query buffer.
in an effort to avoid cache misses and overheads while keeping track of
these, i avoid calling sdsZmallocSize and instead use the sdslen /
bulk-len which can at least give some insight into the problem.
This memory is now added to the total clients memory usage, as well as
the client list.
(cherry picked from commit 7481e513f0507d01381a87046d8d1366c718f94e)
We may access and modify these two variables in signal handler function,
to guarantee them async-signal-safe, so we should set them to volatile
sig_atomic_t type.
It doesn't look like this could have caused any real issue, and it seems that
signals are handled in main thread on most platforms. But we want to follow C
and POSIX standard in signal handler function.
(cherry picked from commit 917043fa438d9bbe9a80fb838fcfd33a7e390952)
Before this commit, we would have continued to add replies to the reply buffer even if client
output buffer limit is reached, so the used memory would keep increasing over the configured limit.
What's more, we shouldn’t write any reply to the client if it is set 'CLIENT_CLOSE_ASAP' flag
because that doesn't conform to its definition and we will close all clients flagged with
'CLIENT_CLOSE_ASAP' in ‘beforeSleep’.
Because of code execution order, before this, we may firstly write to part of the replies to
the socket before disconnecting it, but in fact, we may can’t send the full replies to clients
since OS socket buffer is limited. But this unexpected behavior makes some commands work well,
for instance ACL DELUSER, if the client deletes the current user, we need to send reply to client
and close the connection, but before, we close the client firstly and write the reply to reply
buffer. secondly, we shouldn't do this despite the fact it works well in most cases.
We add a flag 'CLIENT_CLOSE_AFTER_COMMAND' to mark clients, this flag means we will close the
client after executing commands and send all entire replies, so that we can write replies to
reply buffer during executing commands, send replies to clients, and close them later.
We also fix some implicit problems. If client output buffer limit is enforced in 'multi/exec',
all commands will be executed completely in redis and clients will not read any reply instead of
partial replies. Even more, if the client executes 'ACL deluser' the using user in 'multi/exec',
it will not read the replies after 'ACL deluser' just like before executing 'client kill' itself
in 'multi/exec'.
We added some tests for output buffer limit breach during multi-exec and using a pipeline of
many small commands rather than one with big response.
Co-authored-by: Oran Agra <oran@redislabs.com>
(cherry picked from commit 3085577c095a0f3b1261f6dbf016d7701aadab46)
Refine comment of makeThreadKillable().
This commit can be backported to 5.0, only if we also backport cf8a6e3.
Co-authored-by: Oran Agra <oran@redislabs.com>
(cherry picked from commit d2291627305d606a5d3b1e3b3bfa17ab10a3ef32)
