XREAD only supports a special ID of $ and XREADGROUP only supports ^.
make sure not to suggest the wrong one when rerunning an error about unbalanced ID arguments
Co-authored-by: Oran Agra <oran@redislabs.com>
XREADGROUP can output a misleading error message regarding use of the $ special ID.
Here is the example (with some newlines):
```
redis> xreadgroup group workers worker1 count 1 streams mystream
(error) ERR Unbalanced XREAD list of streams: for each stream key an ID or '$' must be specified.
redis> xreadgroup group workers worker1 count 1 streams mystream $
(error) ERR The $ ID is meaningless in the context of XREADGROUP: you want to read the history of this
consumer by specifying a proper ID, or use the > ID to get new messages. The $ ID would just return an empty result set.
redis> xreadgroup group workers worker1 count 1 streams mystream >
1) 1) "mystream"
2) 1) 1) "1673544607848-0"
2) 1) "n"
2) "1"
```
Note that XREADGROUP first returns an error with the following problems in it:
- Command name in the error should be XREADGROUP not XREAD.
- It recommends using $ as an option for a stream ID, then when you try this
(see second XREADGROUP command above), it errors telling you that `$` doesn't
make sense in this context even though the previous error message told you to use it
Suggest that the command name be fixed in the first message, and the second part error
message be amended not to talk about using `$` but `>` instead, this works, see the third
and final XREADGROUP example above.
Fixes#11730, commit message took from simonprickett.
Co-authored-by: Simon Prickett <simon@redislabs.com>
This change attempts to alleviate a minor memory usage degradation for Redis 6.2 and onwards when using rather large objects (~2k) in streams. Introduced in #6281, we pre-allocate the head nodes of a stream to be 4kb, to limit the amount of unnecessary initial reallocations that are done. However, if we only ever allocate one object because 2 objects exceeds the max_stream_entry_size, we never actually shrink it to fit the single item. This can lead to a lot of excessive memory usage. For smaller item sizes this becomes less of an issue, as the overhead decreases as the items become smaller in size.
This commit also changes the MEMORY USAGE of streams, since it was reporting the lpBytes instead of the allocated size. This introduced an observability issue when diagnosing the memory issue, since Redis reported the same amount of used bytes pre and post change, even though the new implementation allocated more memory.
*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. "Fixed" the current code so that seen-time/idle actually refers to interaction
attempts (as documented; breaking change)
2. Added active-time/inactive to refer to successful interaction (what
seen-time/idle used to be)
At first, I tried to avoid changing the behavior of seen-time/idle but then realized
that, in this case, the odds are the people read the docs and implemented their
code based on the docs (which didn't match the behavior).
For the most part, that would work fine, except that issue #9996 was found.
I was working under the assumption that people relied on the docs, and for
the most part, it could have worked well enough. so instead of fixing the docs,
as I would usually do, I fixed the code to match the docs in this particular case.
Note that, in case the consumer has never read any entries, the values
for both "active-time" (XINFO FULL) and "inactive" (XINFO CONSUMERS) will
be -1, meaning here that the consumer was never active.
Note that seen/active time is only affected by XREADGROUP / X[AUTO]CLAIM, not
by XPENDING, XINFO, and other "read-only" stream CG commands (always has been,
even before this PR)
Other changes:
* Another behavioral change (arguably a bugfix) is that XREADGROUP and X[AUTO]CLAIM
create the consumer regardless of whether it was able to perform some reading/claiming
* RDB format change to save the `active_time`, and set it to the same value of `seen_time` in old rdb files.
Resolve an edge case where the ID of a stream is updated retroactively
to an ID lower than the already set max_deleted_entry_id.
Currently, if we have command as below:
**xsetid mystream 1-1 MAXDELETEDID 1-2**
Then we will get the following error:
**(error) ERR The ID specified in XSETID is smaller than the provided max_deleted_entry_id**
Becuase the provided MAXDELETEDID 1-2 is greated than input last-id: 1-1
Then we could assume there is a similar situation:
step 1: we add three items in the mystream
**127.0.0.1:6381> xadd mystream 1-1 a 1
"1-1"
127.0.0.1:6381> xadd mystream 1-2 b 2
"1-2"
127.0.0.1:6381> xadd mystream 1-3 c 3
"1-3"**
step 2: we could check the mystream infomation as below:
**127.0.0.1:6381> xinfo stream mystream
1) "length"
2) (integer) 3
7) "last-generated-id"
8) "1-3"
9) "max-deleted-entry-id"
10) "0-0"
step 3: we delete the item id 1-2 and 1-3 as below:
**127.0.0.1:6381> xdel mystream 1-2
(integer) 1
127.0.0.1:6381> xdel mystream 1-3
(integer) 1**
step 4: we check the mystream information:
127.0.0.1:6381> xinfo stream mystream
1) "length"
2) (integer) 1
7) "last-generated-id"
8) "1-3"
9) "max-deleted-entry-id"
10) "1-3"
we could notice that the **max-deleted-entry-id update to 1-3**, so right now, if we just run:
**xsetid mystream 1-2**
the above command has the same effect with **xsetid mystream 1-2 MAXDELETEDID 1-3**
So we should return an error to the client that **(error) ERR The ID specified in XSETID is smaller than current max_deleted_entry_id**
This is a rare failure mode of a new feature of redis 7 introduced in #9217
(when the incremental part of the ID overflows).
Till now, the outcome of that error was undetermined (could easily result in
`Elements are too large to be stored` wrongly, due to unset `errno`).
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)
Freeze time during execution of scripts and all other commands.
This means that a key is either expired or not, and doesn't change
state during a script execution. resolves#10182
This PR try to add a new `commandTimeSnapshot` function.
The function logic is extracted from `keyIsExpired`, but the related
calls to `fixed_time_expire` and `mstime()` are removed, see below.
In commands, we will avoid calling `mstime()` multiple times
and just use the one that sampled in call. The background is,
e.g. using `PEXPIRE 1` with valgrind sometimes result in the key
being deleted rather than expired. The reason is that both `PEXPIRE`
command and `checkAlreadyExpired` call `mstime()` separately.
There are other more important changes in this PR:
1. Eliminate `fixed_time_expire`, it is no longer needed.
When we want to sample time we should always use a time snapshot.
We will use `in_nested_call` instead to update the cached time in `call`.
2. Move the call for `updateCachedTime` from `serverCron` to `afterSleep`.
Now `commandTimeSnapshot` will always return the sample time, the
`lookupKeyReadWithFlags` call in `getNodeByQuery` will get a outdated
cached time (because `processCommand` is out of the `call` context).
We put the call to `updateCachedTime` in `aftersleep`.
3. Cache the time each time the module lock Redis.
Call `updateCachedTime` in `moduleGILAfterLock`, affecting `RM_ThreadSafeContextLock`
and `RM_ThreadSafeContextTryLock`
Currently the commandTimeSnapshot change affects the following TTL commands:
- SET EX / SET PX
- EXPIRE / PEXPIRE
- SETEX / PSETEX
- GETEX EX / GETEX PX
- TTL / PTTL
- EXPIRETIME / PEXPIRETIME
- RESTORE key TTL
And other commands just use the cached mstime (including TIME).
This is considered to be a breaking change since it can break a script
that uses a loop to wait for a key to expire.
Optimization update from -O2 to -O3 -flto gives up to 5% performance gain
in 'redis-benchmarks-spec-client-runner' tests geomean where GCC 9.4.0 is used for build
* Fix for false-positive warning in bitops.c
Warning appeared with O3, on CentOS during inlininig procedure
* Fixed unitialized streamID within streamTrim() (#1)
Co-authored-by: filipe oliveira <filipecosta.90@gmail.com>
Executing an XAUTOCLAIM command on a stream key in a specific state, with a
specially crafted COUNT argument may cause an integer overflow, a subsequent
heap overflow, and potentially lead to remote code execution.
The problem affects Redis versions 7.0.0 or newer.
The temporary array for deleted entries reply of XAUTOCLAIM was
insufficient, but also in fact the COUNT argument should be used to
control the size of the reply, so instead of terminating the loop by
only counting the claimed entries, we'll count deleted entries as well.
Fix#10968
Addresses CVE-2022-31144
When I read the source codes, I have no idea where the option "age" come from.
Co-authored-by: Ubuntu <lucas.guang.yang1@huawei.com>
Co-authored-by: guybe7 <guy.benoish@redislabs.com>
This PR unifies all the places that test if the current client is the
master client or AOF client, and uses a method to test that on all of
these.
Other than some refactoring, these are the actual implications:
- Replicas **don't** ignore disk error when processing commands not
coming from their master.
**This is important for PING to be used for health check of replicas**
- SETRANGE, APPEND, SETBIT, BITFIELD don't do proto_max_bulk_len check for AOF
- RM_Call in SCRIPT_MODE ignores disk error when coming from master /
AOF
- RM_Call in cluster mode ignores slot check when processing AOF
- Scripts ignore disk error when processing AOF
- Scripts **don't** ignore disk error on a replica, if the command comes
from clients other than the master
- SCRIPT KILL won't kill script coming from AOF
- Scripts **don't** skip OOM check on replica if the command comes from
clients other than the master
Note that Script, AOF, and module clients don't reach processCommand,
which is why some of the changes don't actually have any implications.
Note, reverting the change done to processCommand in 2f4240b9d9
should be dead code due to the above mentioned fact.
we can observe that when adding to a stream without ID there is a duplicate work
on sds creation/freeing/sdslen that costs ~11% of the CPU cycles.
This PR avoids it by not freeing the sds after the first reply.
The expected reduction in CPU cycles is around 9-10%
Additionally, we now pre-allocate the sds to the right size, to avoid realloc.
this brought another ~10% improvement
Co-authored-by: Oran Agra <oran@redislabs.com>
Adds the ability to track the lag of a consumer group (CG), that is, the number
of entries yet-to-be-delivered from the stream.
The proposed constant-time solution is in the spirit of "best-effort."
Partially addresses #8737.
## Description of approach
We add a new "entries_added" property to the stream. This starts at 0 for a new
stream and is incremented by 1 with every `XADD`. It is essentially an all-time
counter of the entries added to the stream.
Given the stream's length and this counter value, we can trivially find the logical
"entries_added" counter of the first ID if and only if the stream is contiguous.
A fragmented stream contains one or more tombstones generated by `XDEL`s.
The new "xdel_max_id" stream property tracks the latest tombstone.
The CG also tracks its last delivered ID's as an "entries_read" counter and
increments it independently when delivering new messages, unless the this
read counter is invalid (-1 means invalid offset). When the CG's counter is
available, the reported lag is the difference between added and read counters.
Lastly, this also adds a "first_id" field to the stream structure in order to make
looking it up cheaper in most cases.
## Limitations
There are two cases in which the mechanism isn't able to track the lag.
In these cases, `XINFO` replies with `null` in the "lag" field.
The first case is when a CG is created with an arbitrary last delivered ID,
that isn't "0-0", nor the first or the last entries of the stream. In this case,
it is impossible to obtain a valid read counter (short of an O(N) operation).
The second case is when there are one or more tombstones fragmenting
the stream's entries range.
In both cases, given enough time and assuming that the consumers are
active (reading and lacking) and advancing, the CG should be able to
catch up with the tip of the stream and report zero lag.
Once that's achieved, lag tracking would resume as normal (until the
next tombstone is set).
## API changes
* `XGROUP CREATE` added with the optional named argument `[ENTRIESREAD entries-read]`
for explicitly specifying the new CG's counter.
* `XGROUP SETID` added with an optional positional argument `[ENTRIESREAD entries-read]`
for specifying the CG's counter.
* `XINFO` reports the maximal tombstone ID, the recorded first entry ID, and total
number of entries added to the stream.
* `XINFO` reports the current lag and logical read counter of CGs.
* `XSETID` is an internal command that's used in replication/aof. It has been added with
the optional positional arguments `[ENTRIESADDED entries-added] [MAXDELETEDID max-deleted-entry-id]`
for propagating the CG's offset and maximal tombstone ID of the stream.
## The generic unsolved problem
The current stream implementation doesn't provide an efficient way to obtain the
approximate/exact size of a range of entries. While it could've been nice to have
that ability (#5813) in general, let alone specifically in the context of CGs, the risk
and complexities involved in such implementation are in all likelihood prohibitive.
## A refactoring note
The `streamGetEdgeID` has been refactored to accommodate both the existing seek
of any entry as well as seeking non-deleted entries (the addition of the `skip_tombstones`
argument). Furthermore, this refactoring also migrated the seek logic to use the
`streamIterator` (rather than `raxIterator`) that was, in turn, extended with the
`skip_tombstones` Boolean struct field to control the emission of these.
Co-authored-by: Guy Benoish <guy.benoish@redislabs.com>
Co-authored-by: Oran Agra <oran@redislabs.com>
Fix#7021#8924#10198
# Intro
Before this commit X[AUTO]CLAIM used to transfer deleted entries from one
PEL to another, but reply with "nil" for every such entry (instead of the entry id).
The idea (for XCLAIM) was that the caller could see this "nil", realize the entry
no longer exists, and XACK it in order to remove it from PEL.
The main problem with that approach is that it assumes there's a correlation
between the index of the "id" arguments and the array indices, which there
isn't (in case some of the input IDs to XCLAIM never existed/read):
```
127.0.0.1:6379> XADD x 1 f1 v1
"1-0"
127.0.0.1:6379> XADD x 2 f1 v1
"2-0"
127.0.0.1:6379> XADD x 3 f1 v1
"3-0"
127.0.0.1:6379> XGROUP CREATE x grp 0
OK
127.0.0.1:6379> XREADGROUP GROUP grp Alice COUNT 2 STREAMS x >
1) 1) "x"
2) 1) 1) "1-0"
2) 1) "f1"
2) "v1"
2) 1) "2-0"
2) 1) "f1"
2) "v1"
127.0.0.1:6379> XDEL x 1 2
(integer) 2
127.0.0.1:6379> XCLAIM x grp Bob 0 0-99 1-0 1-99 2-0
1) (nil)
2) (nil)
```
# Changes
Now, X[AUTO]CLAIM acts in the following way:
1. If one tries to claim a deleted entry, we delete it from the PEL we found it in
(and the group PEL too). So de facto, such entry is not claimed, just cleared
from PEL (since anyway it doesn't exist in the stream)
2. since we never claim deleted entries, X[AUTO]CLAIM will never return "nil"
instead of an entry.
3. add a new element to XAUTOCLAIM's response (see below)
# Knowing which entries were cleared from the PEL
The caller may want to log any entries that were found in a PEL but deleted from
the stream itself (it would suggest that there might be a bug in the application:
trimming the stream while some entries were still no processed by the consumers)
## XCLAIM
the set {XCLAIM input ids} - {XCLAIM returned ids} contains all the entry ids that were
not claimed which means they were deleted (assuming the input contains only entries
from some PEL). The user doesn't need to XACK them because XCLAIM had already
deleted them from the source PEL.
## XAUTOCLAIM
XAUTOCLAIM has a new element added to its reply: it's an array of all the deleted
stream IDs it stumbled upon.
This is somewhat of a breaking change since X[AUTO]CLAIM used to be able to reply
with "nil" and now it can't... But since it was undocumented (and generally a bad idea
to rely on it, as explained above) the breakage is not that bad.
Summary of changes:
1. Rename `redisCommand->name` to `redisCommand->declared_name`, it is a
const char * for native commands and SDS for module commands.
2. Store the [sub]command fullname in `redisCommand->fullname` (sds).
3. List subcommands in `ACL CAT`
4. List subcommands in `COMMAND LIST`
5. `moduleUnregisterCommands` now will also free the module subcommands.
6. RM_GetCurrentCommandName returns full command name
Other changes:
1. Add `addReplyErrorArity` and `addReplyErrorExpireTime`
2. Remove `getFullCommandName` function that now is useless.
3. Some cleanups about `fullname` since now it is SDS.
4. Delete `populateSingleCommand` function from server.h that is useless.
5. Added tests to cover this change.
6. Add some module unload tests and fix the leaks
7. Make error messages uniform, make sure they always contain the full command
name and that it's quoted.
7. Fixes some typos
see the history in #9504, fixes#10124
Co-authored-by: Oran Agra <oran@redislabs.com>
Co-authored-by: guybe7 <guy.benoish@redislabs.com>
Fix#9410
Crucial for the ms and sequence deltas, but I changed all
calls, just in case (e.g. "flags")
Before this commit:
`ms_delta` and `seq_delta` could have overflown, causing `currid` to be wrong,
which in turn would cause `streamTrim` to trim the entire rax node (see new test)
The mess:
Some parts use alsoPropagate for late propagation, others using an immediate one (propagate()),
causing edge cases, ugly/hacky code, and the tendency for bugs
The basic idea is that all commands are propagated via alsoPropagate (i.e. added to a list) and the
top-most call() is responsible for going over that list and actually propagating them (and wrapping
them in MULTI/EXEC if there's more than one command). This is done in the new function,
propagatePendingCommands.
Callers to propagatePendingCommands:
1. top-most call() (we want all nested call()s to add to the also_propagate array and just the top-most
one to propagate them) - via `afterCommand`
2. handleClientsBlockedOnKeys: it is out of call() context and it may propagate stuff - via `afterCommand`.
3. handleClientsBlockedOnKeys edge case: if the looked-up key is already expired, we will propagate the
expire but will not unblock any client so `afterCommand` isn't called. in that case, we have to propagate
the deletion explicitly.
4. cron stuff: active-expire and eviction may also propagate stuff
5. modules: the module API allows to propagate stuff from just about anywhere (timers, keyspace notifications,
threads). I could have tried to catch all the out-of-call-context places but it seemed easier to handle it in one
place: when we free the context. in the spirit of what was done in call(), only the top-most freeing of a module
context may cause propagation.
6. modules: when using a thread-safe ctx it's not clear when/if the ctx will be freed. we do know that the module
must lock the GIL before calling RM_Replicate/RM_Call so we propagate the pending commands when
releasing the GIL.
A "known limitation", which were actually a bug, was fixed because of this commit (see propagate.tcl):
When using a mix of RM_Call with `!` and RM_Replicate, the command would propagate out-of-order:
first all the commands from RM_Call, and then the ones from RM_Replicate
Another thing worth mentioning is that if, in the past, a client would issue a MULTI/EXEC with just one
write command the server would blindly propagate the MULTI/EXEC too, even though it's redundant.
not anymore.
This commit renames propagate() to propagateNow() in order to cause conflicts in pending PRs.
propagatePendingCommands is the only caller of propagateNow, which is now a static, internal helper function.
Optimizations:
1. alsoPropagate will not add stuff to also_propagate if there's no AOF and replicas
2. alsoPropagate reallocs also_propagagte exponentially, to save calls to memmove
Bugfixes:
1. CONFIG SET can create evictions, sending notifications which can cause to dirty++ with modules.
we need to prevent it from propagating to AOF/replicas
2. We need to set current_client in RM_Call. buggy scenario:
- CONFIG SET maxmemory, eviction notifications, module hook calls RM_Call
- assertion in lookupKey crashes, because current_client has CONFIG SET, which isn't CMD_WRITE
3. minor: in eviction, call propagateDeletion after notification, like active-expire and all commands
(we always send a notification before propagating the command)
Script unit is a new unit located on script.c.
Its purpose is to provides an API for functions (and eval)
to interact with Redis. Interaction includes mostly
executing commands, but also functionalities like calling
Redis back on long scripts or check if the script was killed.
The interaction is done using a scriptRunCtx object that
need to be created by the user and initialized using scriptPrepareForRun.
Detailed list of functionalities expose by the unit:
1. Calling commands (including all the validation checks such as
acl, cluster, read only run, ...)
2. Set Resp
3. Set Replication method (AOF/REPLICATION/NONE)
4. Call Redis back to on long running scripts to allow Redis reply
to clients and perform script kill
The commit introduce the new unit and uses it on eval commands to
interact with Redis.
Adds the ability to autogenerate the sequence part of the millisecond-only explicit ID specified for `XADD`. This is useful in case added entries have an externally-provided timestamp without sub-millisecond resolution.
Moves ZPOP ... 0 fast exit path after type check to reply with
WRONGTYPE. In the past it will return an empty array.
Also now count is not allowed to be negative.
see #9680
before:
```
127.0.0.1:6379> set zset str
OK
127.0.0.1:6379> zpopmin zset 0
(empty array)
127.0.0.1:6379> zpopmin zset -1
(empty array)
```
after:
```
127.0.0.1:6379> set zset str
OK
127.0.0.1:6379> zpopmin zset 0
(error) WRONGTYPE Operation against a key holding the wrong kind of value
127.0.0.1:6379> zpopmin zset -1
(error) ERR value is out of range, must be positive
```
When calling `XADD` with a predefined id (instead of `*`) there's no need to run
the code which replaces the supplied id with itself. Only when we pass a wildcard
id we need to do this.
For apps which always supply their own id this is a slight optimization.
- fix possible heap corruption in ziplist and listpack resulting by trying to
allocate more than the maximum size of 4GB.
- prevent ziplist (hash and zset) from reaching size of above 1GB, will be
converted to HT encoding, that's not a useful size.
- prevent listpack (stream) from reaching size of above 1GB.
- XADD will start a new listpack if the new record may cause the previous
listpack to grow over 1GB.
- XADD will respond with an error if a single stream record is over 1GB
- List type (ziplist in quicklist) was truncating strings that were over 4GB,
now it'll respond with an error.
Co-authored-by: sundb <sundbcn@gmail.com>
The `cmd` argument was completely unused, and all the code that bothered to pass it was unnecessary.
This is a prepartion for a future commit that treats subcommands as commands
We want to add COUNT option for BLPOP.
But we can't do it without breaking compatibility due to the command arguments syntax.
So this commit introduce two new commands.
Syntax for the new LMPOP command:
`LMPOP numkeys [<key> ...] LEFT|RIGHT [COUNT count]`
Syntax for the new BLMPOP command:
`BLMPOP timeout numkeys [<key> ...] LEFT|RIGHT [COUNT count]`
Some background:
- LPOP takes one key, and can return multiple elements.
- BLPOP takes multiple keys, but returns one element from just one key.
- LMPOP can take multiple keys and return multiple elements from just one key.
Note that LMPOP/BLMPOP can take multiple keys, it eventually operates on just one key.
And it will propagate as LPOP or RPOP with the COUNT option.
As a new command, it still return NIL if we can't pop any elements.
For the normal response is nested arrays in RESP2 and RESP3, like:
```
LMPOP/BLMPOP
1) keyname
2) 1) element1
2) element2
```
I.e. unlike BLPOP that returns a key name and one element so it uses a flat array,
and LPOP that returns multiple elements with no key name, and again uses a flat array,
this one has to return a nested array, and it does for for both RESP2 and RESP3 (like SCAN does)
Some discuss can see: #766#8824
Part one of implementing #8702 (taking hashes first before other types)
## Description of the feature
1. Change ziplist encoded hash objects to listpack encoding.
2. Convert existing ziplists on RDB loading time. an O(n) operation.
## Rdb format changes
1. Add RDB_TYPE_HASH_LISTPACK rdb type.
2. Bump RDB_VERSION to 10
## Interface changes
1. New `hash-max-listpack-entries` config is an alias for `hash-max-ziplist-entries` (same with `hash-max-listpack-value`)
2. OBJECT ENCODING will return `listpack` instead of `ziplist`
## Listpack improvements:
1. Support direct insert, replace integer element (rather than convert back and forth from string)
3. Add more listpack capabilities to match the ziplist ones (like `lpFind`, `lpRandomPairs` and such)
4. Optimize element length fetching, avoid multiple calculations
5. Use inline to avoid function call overhead.
## Tests
1. Add a new test to the RDB load time conversion
2. Adding the listpack unit tests. (based on the one in ziplist.c)
3. Add a few "corrupt payload: fuzzer findings" tests, and slightly modify existing ones.
Co-authored-by: Oran Agra <oran@redislabs.com>
Recently we found two issues in the fuzzer tester: #9302#9285
After fixing them, more problems surfaced and this PR (as well as #9297) aims to fix them.
Here's a list of the fixes
- Prevent an overflow when allocating a dict hashtable
- Prevent OOM when attempting to allocate a huge string
- Prevent a few invalid accesses in listpack
- Improve sanitization of listpack first entry
- Validate integrity of stream consumer groups PEL
- Validate integrity of stream listpack entry IDs
- Validate ziplist tail followed by extra data which start with 0xff
Co-authored-by: sundb <sundbcn@gmail.com>
Fixes:
- When a consumer is created as a side effect, redis didn't issue a keyspace notification,
nor incremented the server.dirty (affects periodic snapshots).
this was a bug in XREADGROUP, XCLAIM, and XAUTOCLAIM.
- When attempting to delete a non-existent consumer, don't issue a keyspace notification
and don't increment server.dirty
this was a bug in XGROUP DELCONSUMER
Other changes:
- Changed streamLookupConsumer() to always only do lookup consumer (never do implicit creation),
Its last seen time is updated unless the SLC_NO_REFRESH flag is specified.
- Added streamCreateConsumer() to create a new consumer. When the creation is successful,
it will notify and dirty++ unless the SCC_NO_NOTIFY or SCC_NO_DIRTIFY flags is specified.
- Changed streamDelConsumer() to always only do delete consumer.
- Added keyspace notifications tests about stream events.
This seems to be an unimportant bug that was accidentally generated. If the user does not specify limit in streamParseAddOrTrimArgsOrReply, the initial value of args->limit is 100 * server.stream_node_max_entries, which may lead to out of bounds, and then the default function of limit in xadd becomes invalid (this failure occurs in streamTrim).
Additionally, provide sane default for args->limit in case stream_node_max_entries is set to 0.
Co-authored-by: lizhaolong.lzl <lizhaolong.lzl@B-54MPMD6R-0221.local>
Co-authored-by: Oran Agra <oran@redislabs.com>
Co-authored-by: guybe7 <guy.benoish@redislabs.com>
The call to raxNext didn't really progress in the rax, since we were already on the last item.
instead, all it does is check that it is indeed a valid item, so the new code clearer.
This PR adds a spell checker CI action that will fail future PRs if they introduce typos and spelling mistakes.
This spell checker is based on blacklist of common spelling mistakes, so it will not catch everything,
but at least it is also unlikely to cause false positives.
Besides that, the PR also fixes many spelling mistakes and types, not all are a result of the spell checker we use.
Here's a summary of other changes:
1. Scanned the entire source code and fixes all sorts of typos and spelling mistakes (including missing or extra spaces).
2. Outdated function / variable / argument names in comments
3. Fix outdated keyspace masks error log when we check `config.notify-keyspace-events` in loadServerConfigFromString.
4. Trim the white space at the end of line in `module.c`. Check: https://github.com/redis/redis/pull/7751
5. Some outdated https link URLs.
6. Fix some outdated comment. Such as:
- In README: about the rdb, we used to said create a `thread`, change to `process`
- dbRandomKey function coment (about the dictGetRandomKey, change to dictGetFairRandomKey)
- notifyKeyspaceEvent fucntion comment (add type arg)
- Some others minor fix in comment (Most of them are incorrectly quoted by variable names)
7. Modified the error log so that users can easily distinguish between TCP and TLS in `changeBindAddr`
The decision to stop trimming due to LIMIT in XADD and XTRIM was after the limit was reached.
i.e. the code was deleting **at least** that count of records (from the LIMIT argument's perspective, not the MAXLEN),
instead of **up to** that count of records.
see #9046
xtrimCommand call streamParseAddOrTrimArgsOrReply should use xadd==0.
When the syntax is valid, it does not cause any bugs because the params of XADD is superset of XTRIM.
Just XTRIM will not respond with error on invalid syntax. The syntax of XADD will also be accpeted by XTRIM.
Fix out of range error messages to be clearer (avoid mentioning 9223372036854775807)
* Fix XAUTOCLAIM COUNT option confusing error msg
* Fix other RPOP and alike error message to mention positive
This command used to return the last scanned entry id as the cursor,
instead of the next one to be scanned.
so in the next call, the user could / should have sent `(cursor` and not
just `cursor` if he wanted to avoid scanning the same record twice.
Scanning the record twice would look odd if someone is checking what
exactly was scanned, but it also has a side effect of incrementing the
delivery count twice.
the corrupt-dump-fuzzer test found a case where an access to a corrupt
stream would have caused accessing to uninitialized memory.
now it'll panic instead.
The issue was that there was a stream that says it has more than 0
records, but looking for the max ID came back empty handed.
p.s. when sanitize-dump-payload is used, this corruption is detected,
and the RESTORE command is gracefully rejected.
