1. 08 Mar, 2023 18 commits
  2. 28 Feb, 2023 1 commit
    • uriyage's avatar
      Try to trim strings only when applicable (#11817) · 9d336ac3
      uriyage authored
      
      
      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: default avatarOran Agra <oran@redislabs.com>
      Co-authored-by: default avatarsundb <sundbcn@gmail.com>
      9d336ac3
  3. 23 Feb, 2023 1 commit
    • Chen Tianjie's avatar
      Add CLIENT NO-TOUCH for clients to run commands without affecting LRU/LFU of keys (#11483) · 897c3d52
      Chen Tianjie authored
      
      
      When no-touch mode is enabled, the client will not touch LRU/LFU of the
      keys it accesses, except when executing command `TOUCH`.
      This allows inspecting or modifying the key-space without affecting their eviction.
      
      Changes:
      - A command `CLIENT NO-TOUCH ON|OFF` to switch on and off this mode.
      - A client flag `#define CLIENT_NOTOUCH (1ULL<<45)`, which can be shown
        with `CLIENT INFO`, by the letter "T" in the "flags" field.
      - Clear `NO-TOUCH` flag in `clearClientConnectionState`, which is used by `RESET`
        command and resetting temp clients used by modules.
      - Also clear `NO-EVICT` flag in `clearClientConnectionState`, this might have been an
        oversight, spotted by @madolson.
      - A test using `DEBUG OBJECT` command to verify that LRU stat is not touched when
        no-touch mode is on.
      Co-authored-by: default avatarchentianjie <chentianjie@alibaba-inc.com>
      Co-authored-by: default avatarMadelyn Olson <34459052+madolson@users.noreply.github.com>
      Co-authored-by: default avatarsundb <sundbcn@gmail.com>
      897c3d52
  4. 16 Feb, 2023 1 commit
    • Oran Agra's avatar
      Cleanup around script_caller, fix tracking of scripts and ACL logging for RM_Call (#11770) · 233abbbe
      Oran Agra authored
      * 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)
      233abbbe
  5. 14 Feb, 2023 1 commit
    • guybe7's avatar
      SCAN/RANDOMKEY and lazy-expire (#11788) · fd82bccd
      guybe7 authored
      Starting from Redis 7.0 (#9890) we started wrapping everything a command
       propagates with MULTI/EXEC. The problem is that both SCAN and RANDOMKEY can
      lazy-expire arbitrary keys (similar behavior to active-expire), and put DELs in a transaction.
      
      Fix: When these commands are called without a parent exec-unit (e.g. not in EVAL or
      MULTI) we avoid wrapping their DELs in a transaction (for the same reasons active-expire
      and eviction avoids a transaction)
      
      This PR adds a per-command flag that indicates that the command may touch arbitrary
      keys (not the ones in the arguments), and uses that flag to avoid the MULTI-EXEC.
      For now, this flag is internal, since we're considering other solutions for the future.
      
      Note for cluster mode: if SCAN/RANDOMKEY is inside EVAL/MULTI it can still cause the
      same situation (as it always did), but it won't cause a CROSSSLOT because replicas and AOF
      do not perform slot checks.
      The problem with the above is mainly for 3rd party ecosystem tools that propagate commands
      from master to master, or feed an AOF file with redis-cli into a master.
      This PR aims to fix the regression in redis 7.0, and we opened #11792 to try to handle the
      bigger problem with lazy expire better for another release.
      fd82bccd
  6. 09 Feb, 2023 1 commit
    • Meir Shpilraien (Spielrein)'s avatar
      Match REDISMODULE_OPEN_KEY_* flags to LOOKUP_* flags (#11772) · 5c3938d5
      Meir Shpilraien (Spielrein) authored
      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.
      5c3938d5
  7. 11 Jan, 2023 1 commit
  8. 04 Jan, 2023 1 commit
  9. 01 Jan, 2023 1 commit
    • ranshid's avatar
      reprocess command when client is unblocked on keys (#11012) · 383d902c
      ranshid authored
      *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: default avatarOran Agra <oran@redislabs.com>
      Signed-off-by: default avatarRan Shidlansik <ranshid@amazon.com>
      383d902c
  10. 20 Dec, 2022 1 commit
    • guybe7's avatar
      Cleanup: Get rid of server.core_propagates (#11572) · 9c7c6924
      guybe7 authored
      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
      9c7c6924
  11. 09 Dec, 2022 1 commit
    • Binbin's avatar
      Fix zuiFind crash / RM_ScanKey hang on SET object listpack encoding (#11581) · 20854cb6
      Binbin authored
      
      
      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: default avatarOran Agra <oran@redislabs.com>
      Co-authored-by: default avatarViktor Söderqvist <viktor.soderqvist@est.tech>
      20854cb6
  12. 07 Dec, 2022 1 commit
    • Harkrishn Patro's avatar
      Optimize client memory usage tracking operation while client eviction is disabled (#11348) · c0267b3f
      Harkrishn Patro authored
      
      
      ## Issue
      During the client input/output buffer processing, the memory usage is
      incrementally updated to keep track of clients going beyond a certain
      threshold `maxmemory-clients` to be evicted. However, this additional
      tracking activity leads to unnecessary CPU cycles wasted when no
      client-eviction is required. It is applicable in two cases.
      
      * `maxmemory-clients` is set to `0` which equates to no client eviction
        (applicable to all clients)
      * `CLIENT NO-EVICT` flag is set to `ON` which equates to a particular
        client not applicable for eviction.  
      
      ## Solution
      * Disable client memory usage tracking during the read/write flow when
        `maxmemory-clients` is set to `0` or `client no-evict` is `on`.
        The memory usage is tracked only during the `clientCron` i.e. it gets
        periodically updated.
      * Cleanup the clients from the memory usage bucket when client eviction
        is disabled.
      * When the maxmemory-clients config is enabled or disabled at runtime,
        we immediately update the memory usage buckets for all clients (tested
        scanning 80000 took some 20ms)
      
      Benchmark shown that this can improve performance by about 5% in
      certain situations.
      Co-authored-by: default avatarOran Agra <oran@redislabs.com>
      c0267b3f
  13. 06 Dec, 2022 1 commit
    • Viktor Söderqvist's avatar
      When converting a set to dict, presize for one more element to be added (#11559) · 8a315fc2
      Viktor Söderqvist authored
      
      
      In most cases when a listpack or intset is converted to a dict, the conversion
      is trigged when adding an element. The extra element is added after conversion
      to dict (in all cases except when the conversion is triggered by
      set-max-intset-entries being reached).
      
      If set-max-listpack-entries is set to a power of two, let's say 128, when
      adding the 129th element, the 128 element listpack is first converted to a dict
      with a hashtable presized for 128 elements. After converting to dict, the 129th
      element is added to the dict which immediately triggers incremental rehashing
      to size 256.
      
      This commit instead presizes the dict to one more element, with the assumption
      that conversion to dict is followed by adding another element, so the dict
      doesn't immediately need rehashing.
      Co-authored-by: default avatarsundb <sundbcn@gmail.com>
      Co-authored-by: default avatarOran Agra <oran@redislabs.com>
      8a315fc2
  14. 30 Nov, 2022 2 commits
    • filipe oliveira's avatar
      changing addReplySds and sdscat to addReplyStatusLength() within luaReplyToRedisReply() (#11556) · 68e87eb0
      filipe oliveira authored
      profiling EVALSHA\ we see that luaReplyToRedisReply takes 8.73% out of the
      56.90% of luaCallFunction CPU cycles. 
      
      Using addReplyStatusLength instead of directly composing the protocol to avoid
      sdscatprintf and addReplySds ( which imply multiple sdslen calls ).
      
      The new approach drops
      luaReplyToRedisReply CPU cycles to 3.77%                                                                                                                                           
      68e87eb0
    • Huang Zhw's avatar
      Add a special notification unlink available only for modules (#9406) · c8181314
      Huang Zhw authored
      
      
      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: default avatarOran Agra <oran@redislabs.com>
      c8181314
  15. 29 Nov, 2022 1 commit
    • filipe oliveira's avatar
      Reduce eval related overhead introduced in v7.0 by evalCalcFunctionName (#11521) · 7dfd7b91
      filipe oliveira authored
      
      
      As being discussed in #10981 we see a degradation in performance
      between v6.2 and v7.0 of Redis on the EVAL command. 
      
      After profiling the current unstable branch we can see that we call the
      expensive function evalCalcFunctionName twice. 
      
      The current "fix" is to basically avoid calling evalCalcFunctionName and
      even dictFind(lua_scripts) twice for the same command.
      Instead we cache the current script's dictEntry (for both Eval and Functions)
      in the current client so we don't have to repeat these calls.
      The exception would be when doing an EVAL on a new script that's not yet
      in the script cache. in that case we will call evalCalcFunctionName (and even
      evalExtractShebangFlags) twice.
      Co-authored-by: default avatarOran Agra <oran@redislabs.com>
      7dfd7b91
  16. 28 Nov, 2022 1 commit
  17. 27 Nov, 2022 1 commit
    • Binbin's avatar
      Add redis_ prefix for member2struct, avoid redefined warning in FreeBSD (#11549) · a7cecf37
      Binbin authored
      It look like it will generate a warning in FreeBSD:
      ```
        ./server.h:105:9: warning: 'member2struct' macro redefined [-Wmacro-redefined]
        #define member2struct(struct_name, member_name, member_addr) \
                ^
        /usr/include/sys/param.h:365:9: note: previous definition is here
        #define member2struct(s, m, x)                                          \
                ^
      ```
      
      Add a `redis_` prefix to it, avoid the warning, introduced in #11511
      a7cecf37
  18. 24 Nov, 2022 2 commits
    • Meir Shpilraien (Spielrein)'s avatar
      Module API to allow writes after key space notification hooks (#11199) · abc345ad
      Meir Shpilraien (Spielrein) authored
      ### 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: default avatarOran Agra <oran@redislabs.com>
      Co-authored-by: default avatarYossi Gottlieb <yossigo@gmail.com>
      Co-authored-by: default avatarMadelyn Olson <34459052+madolson@users.noreply.github.com>
      abc345ad
    • Binbin's avatar
      Fix sanitizer warning, use offsetof instread of member_offset (#11539) · ca174e1d
      Binbin authored
      
      
      In #11511 we introduced member_offset which has a sanitizer warning:
      ```
      multi.c:390:26: runtime error: member access within null pointer of type 'watchedKey' (aka 'struct watchedKey')
      SUMMARY: UndefinedBehaviorSanitizer: undefined-behavior multi.c:390:26
      ```
      
      We can use offsetof() from stddef.h. This is part of the standard lib
      just to avoid this UB :) Sanitizer should not complain after we change
      this.
      
      1. Use offsetof instead of member_offset, so we can delete this now
      2. Changed (uint8_t*) cast to (char*).
      
      This does not matter much but according to standard, we are only allowed
      to cast pointers to its own type, char* and void*. Let's try to follow
      the rules.
      
      This change was suggested by tezc and the comments is also from him.
      Co-authored-by: default avatarOzan Tezcan <ozantezcan@gmail.com>
      ca174e1d
  19. 23 Nov, 2022 1 commit
    • Mingyi Kang's avatar
      optimize unwatchAllKeys() (#11511) · 3b462ce5
      Mingyi Kang authored
      In unwatchAllKeys() function, we traverse all the keys watched by the client,
      and for each key we need to remove the client from the list of clients watching that key.
      This is implemented by listSearchKey which traverses the list of clients.
      
      If we can reach the node of the list of clients from watchedKey in O(1) time,
      then we do not need to call listSearchKey anymore.
      
      Changes in this PR: put the node of the list of clients of each watched key in the
      db inside the watchedKey structure. In this way, for every key watched by the client,
      we can get the watchedKey structure and then reach the node in the list of clients in
      db->watched_keys to remove it from that list.
      From the perspective of the list of clients watching the key, the list node is inside a
      watchedKey structure, so we can get to the watchedKey struct from the listnode by
      struct member offset math. And because of this, node->value is not used, we can point
      node->value to the list itself, so that we don't need to fetch the list of clients from the dict.
      3b462ce5
  20. 17 Nov, 2022 1 commit
    • Ping Xie's avatar
      Introduce Shard IDs to logically group nodes in cluster mode (#10536) · 203b12e4
      Ping Xie authored
      Introduce Shard IDs to logically group nodes in cluster mode.
      1. Added a new "shard_id" field to "cluster nodes" output and nodes.conf after "hostname"
      2. Added a new PING extension to propagate "shard_id"
      3. Handled upgrade from pre-7.2 releases automatically
      4. Refactored PING extension assembling/parsing logic
      
      Behavior of Shard IDs:
      
      Replicas will always follow the shards of their reported primaries. If a primary updates its shard ID, the replica will follow. (This need not follow for cluster v2) This is not an expected use case.
      203b12e4
  21. 16 Nov, 2022 1 commit
    • sundb's avatar
      Add listpack encoding for list (#11303) · 2168ccc6
      sundb authored
      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.
      2168ccc6