1. 26 Apr, 2022 2 commits
    • Madelyn Olson's avatar
      Set replicas to panic on disk errors, and optionally panic on replication errors (#10504) · 6fa8e4f7
      Madelyn Olson authored
      * Till now, replicas that were unable to persist, would still execute the commands
        they got from the master, now they'll panic by default, and we add a new
        `replica-ignore-disk-errors` config to change that.
      * Till now, when a command failed on a replica or AOF-loading, it only logged a
        warning and a stat, we add a new `propagation-error-behavior` config to allow
        panicking in that state (may become the default one day)
      
      Note that commands that fail on the replica can either indicate a bug that could
      cause data inconsistency between the replica and the master, or they could be
      in some cases (specifically in previous versions), a result of a command (e.g. EVAL)
      that failed on the master, but still had to be propagated to fail on the replica as well.
      6fa8e4f7
    • Madelyn Olson's avatar
      By default prevent cross slot operations in functions and scripts with # (#10615) · efcd1bf3
      Madelyn Olson authored
      Adds the `allow-cross-slot-keys` flag to Eval scripts and Functions to allow
      scripts to access keys from multiple slots.
      The default behavior is now that they are not allowed to do that (unlike before).
      This is a breaking change for 7.0 release candidates (to be part of 7.0.0), but
      not for previous redis releases since EVAL without shebang isn't doing this check.
      
      Note that the check is done on both the keys declared by the EVAL / FCALL command
      arguments, and also the ones used by the script when making a `redis.call`.
      
      A note about the implementation, there seems to have been some confusion
      about allowing access to non local keys. I thought I missed something in our
      wider conversation, but Redis scripts do block access to non-local keys.
      So the issue was just about cross slots being accessed.
      efcd1bf3
  2. 25 Apr, 2022 3 commits
  3. 20 Apr, 2022 4 commits
    • filipe oliveira's avatar
      Optimization: Use either monotonic or wall-clock to measure command execution... · 3cd8baf6
      filipe oliveira authored
      
      Optimization: Use either monotonic or wall-clock to measure command execution time, to regain up to 4% execution time (#10502)
      
      In #7491 (part of redis 6.2), we started using the monotonic timer instead of mstime to measure
      command execution time for stats, apparently this meant sampling the clock 3 times per command
      rather than two (wince we also need the wall-clock time).
      In some cases this causes a significant overhead.
      
      This PR fixes that by avoiding the use of monotonic timer, except for the cases were we know it
      should be extremely fast.
      This PR also adds a new INFO field called `monotonic_clock` that shows which clock redis is using.
      Co-authored-by: default avatarOran Agra <oran@redislabs.com>
      3cd8baf6
    • Oran Agra's avatar
      Fixes around clients that must be obeyed. Replica report disk errors in PING. (#10603) · ee220599
      Oran Agra authored
      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 2f4240b9
      should be dead code due to the above mentioned fact.
      ee220599
    • yoav-steinberg's avatar
      Optimized `hdr_value_at_percentile` (#10606) · 5075e743
      yoav-steinberg authored
      `hdr_value_at_percentile()` is part of the Hdr_Histogram library
      used when generating `latencystats` report. 
      
      There's a pending optimization for this function which greatly
      affects the performance of `info latencystats`.
      https://github.com/HdrHistogram/HdrHistogram_c/pull/107
      
      
      
      This PR:
      1. Upgrades the sources in _deps/hdr_histogram_ to the latest Hdr_Histogram
        version 0.11.5
      2. Applies the referenced optimization.
      3. Adds minor documentation about the hdr_histogram dependency which was
        missing under _deps/README.md_.
      
      benchmark on my machine:
      running: `redis-benchmark -n 100000 info latencystats` on a clean build with no data.
      
      | benchmark | RPS |
      | ---- | ---- |
      | before upgrade to v0.11.05  | 7,681 |
      | before optimization | 12,474 |
      | after optimization | 52,606 |
      Co-authored-by: default avatarfilipe oliveira <filipecosta.90@gmail.com>
      5075e743
    • David CARLIER's avatar
      Add socket-mark-id support for marking sockets. (#10349) · aba2865c
      David CARLIER authored
      Add a configuration option to attach an operating system-specific identifier to Redis sockets, supporting advanced network configurations using iptables (Linux) or ipfw (FreeBSD).
      aba2865c
  4. 19 Apr, 2022 1 commit
    • judeng's avatar
      Fixes around AOF failed rewrite rate limiting (#10582) · d4cbd814
      judeng authored
      
      
      Changes:
      1. Check the failed rewrite time threshold only when we actually consider triggering a rewrite.
        i.e. this should be the last condition tested, since the test has side effects (increasing time threshold)
        Could have happened in some rare scenarios 
      2. no limit in startup state (e.g. after restarting redis that previously failed and had many incr files)
      3. the “triggered the limit” log would be recorded only when the limit status is returned
      4. remove failure count in log (could be misleading in some cases)
      Co-authored-by: default avatarchenyang8094 <chenyang8094@users.noreply.github.com>
      Co-authored-by: default avatarOran Agra <oran@redislabs.com>
      d4cbd814
  5. 13 Apr, 2022 1 commit
    • guybe7's avatar
      Add the deprecated_since field in command args of COMMAND DOCS (#10545) · e875ff89
      guybe7 authored
      Apparently, some modules can afford deprecating command arguments
      (something that was never done in Redis, AFAIK), so in order to represent
      this piece of information, we added the `deprecated_since` field to redisCommandArg
      (in symmetry to the already existing `since` field).
      
      This commit adds `const char *deprecated_since` to `RedisModuleCommandArg`,
      which is technically a breaking change, but since 7.0 was not released yet, we decided to let it slide
      e875ff89
  6. 11 Apr, 2022 1 commit
    • zhaozhao.zz's avatar
      Durability enhancement for appendfsync=always policy (#9678) · 1a7765cb
      zhaozhao.zz authored
      Durability of database is a big and old topic, in this regard Redis use AOF to
      support it, and `appendfsync=alwasys` policy is the most strict level, guarantee
      all data is both written and synced on disk before reply success to client.
      
      But there are some cases have been overlooked, and could lead to durability broken.
      
      1. The most clear one is about threaded-io mode
         we should also set client's write handler with `ae_barrier` in
         `handleClientsWithPendingWritesUsingThreads`, or the write handler would be
         called after read handler in the next event loop, it means the write command result
         could be replied to client before flush to AOF.
      2. About blocked client (mostly by module)
         in `beforeSleep()`, `handleClientsBlockedOnKeys()` should be called before
         `flushAppendOnlyFile()`, in case the unblocked clients modify data without persistence
         but send reply.
      3. When handling `ProcessingEventsWhileBlocked`
         normally it takes place when lua/function/module timeout, and we give a chance to users
         to kill the slow operation, but we should call `flushAppendOnlyFile()` before
         `handleClientsWithPendingWrites()`, in case the other clients in the last event loop get
         acknowledge before data persistence.
         for a instance:
         ```
         in the same event loop
         client A executes set foo bar
         client B executes eval "for var=1,10000000,1 do end" 0
         ```
         after the script timeout, client A will get `OK` but lose data after restart (kill redis when
         timeout) if we don't flush the write command to AOF.
      4. A more complex case about `ProcessingEventsWhileBlocked`
         it is lua timeout in transaction, for example
         `MULTI; set foo bar; eval "for var=1,10000000,1 do end" 0; EXEC`, then client will get set
         command's result before the whole transaction done, that breaks atomicity too.
         fortunately, it's already fixed by #5428 (although it's not the original purpose just a side
         effect : )), but module timeout should be fixed too.
      
      case 1, 2, 3 are fixed in this commit, the module issue in case 4 needs a followup PR.
      1a7765cb
  7. 10 Apr, 2022 1 commit
    • guybe7's avatar
      COMMAND DOCS shows module name, where applicable (#10544) · 719db14e
      guybe7 authored
      Add field to COMMAND DOCS response to denote the name of the module
      that added that command.
      COMMAND LIST can filter by module, but if you get the full commands list,
      you may still wanna know which command belongs to which module.
      The alternative would be to do MODULE LIST, and then multiple calls to COMMAND LIST
      719db14e
  8. 25 Mar, 2022 1 commit
    • zhaozhao.zz's avatar
      optimize(remove) usage of client's pending_querybuf (#10413) · 78bef6e1
      zhaozhao.zz authored
      To remove `pending_querybuf`, the key point is reusing `querybuf`, it means master client's `querybuf` is not only used to parse command, but also proxy to sub-replicas.
      
      1. add a new variable `repl_applied` for master client to record how many data applied (propagated via `replicationFeedStreamFromMasterStream()`) but not trimmed in `querybuf`.
      
      2. don't sdsrange `querybuf` in `commandProcessed()`, we trim it to `repl_applied` after the whole replication pipeline processed to avoid fragmented `sdsrange`. And here are some scenarios we cannot trim to `qb_pos`:
          * we don't receive complete command from master
          * master client blocked because of client pause
          * IO threads operate read, master client flagged with CLIENT_PENDING_COMMAND
      
          In these scenarios, `qb_pos` points to the part of the current command or the beginning of next command, and the current command is not applied yet, so the `repl_applied` is not equal to `qb_pos`.
      
      Some other notes:
      * Do not do big arg optimization on master client, since we can only sdsrange `querybuf` after data sent to replicas.
      * Set `qb_pos` and `repl_applied` to 0 when `freeClient` in `replicationCacheMaster`.
      * Rewrite `processPendingCommandsAndResetClient` to `processPendingCommandAndInputBuffer`, let `processInputBuffer` to be called successively after `processCommandAndResetClient`.
      78bef6e1
  9. 22 Mar, 2022 1 commit
    • Meir Shpilraien (Spielrein)'s avatar
      Add new RM_Call flags for script mode, no writes, and error replies. (#10372) · f3855a09
      Meir Shpilraien (Spielrein) authored
      The PR extends RM_Call with 3 new capabilities using new flags that
      are given to RM_Call as part of the `fmt` argument.
      It aims to assist modules that are getting a list of commands to be
      executed from the user (not hard coded as part of the module logic),
      think of a module that implements a new scripting language...
      
      * `S` - Run the command in a script mode, this means that it will raise an
        error if a command which are not allowed inside a script (flaged with the
        `deny-script` flag) is invoked (like SHUTDOWN). In addition, on script mode,
        write commands are not allowed if there is not enough good replicas (as
        configured with `min-replicas-to-write`) and/or a disk error happened.
      
      * `W` - no writes mode, Redis will reject any command that is marked with `write`
        flag. Again can be useful to modules that implement a new scripting language
        and wants to prevent any write commands.
      
      * `E` - Return errors as RedisModuleCallReply. Today the errors that happened
        before the command was invoked (like unknown commands or acl error) return
        a NULL reply and set errno. This might be missing important information about
        the failure and it is also impossible to just pass the error to the user using
        RM_ReplyWithCallReply. This new flag allows you to get a RedisModuleCallReply
        object with the relevant error message and treat it as if it was an error that was
        raised by the command invocation.
      
      Tests were added to verify the new code paths.
      
      In addition small refactoring was done to share some code between modules,
      scripts, and `processCommand` function:
      1. `getAclErrorMessage` was added to `acl.c` to unified to log message extraction
        from the acl result
      2. `checkGoodReplicasStatus` was added to `replication.c` to check the status of
        good replicas. It is used on `scriptVerifyWriteCommandAllow`, `RM_Call`, and
        `processCommand`.
      3. `writeCommandsGetDiskErrorMessage` was added to `server.c` to get the error
        message on persistence failure. Again it is used on `scriptVerifyWriteCommandAllow`,
        `RM_Call`, and `processCommand`.
      f3855a09
  10. 15 Mar, 2022 1 commit
    • yoav-steinberg's avatar
      Optimization: remove `updateClientMemUsage` from i/o threads. (#10401) · cf6dcb7b
      yoav-steinberg authored
      In a benchmark we noticed we spend a relatively long time updating the client
      memory usage leading to performance degradation.
      Before #8687 this was performed in the client's cron and didn't affect performance.
      But since introducing client eviction we need to perform this after filling the input
      buffers and after processing commands. This also lead me to write this code to be
      thread safe and perform it in the i/o threads.
      
      It turns out that the main performance issue here is related to atomic operations
      being performed while updating the total clients memory usage stats used for client
      eviction (`server.stat_clients_type_memory[]`). This update needed to be atomic
      because `updateClientMemUsage()` was called from the IO threads.
      
      In this commit I make sure to call `updateClientMemUsage()` only from the main thread.
      In case of threaded IO I call it for each client during the "fan-in" phase of the read/write
      operation. This also means I could chuck the `updateClientMemUsageBucket()` function
      which was called during this phase and embed it into `updateClientMemUsage()`.
      
      Profiling shows this makes `updateClientMemUsage()` (on my x86_64 linux) roughly x4 faster.
      cf6dcb7b
  11. 09 Mar, 2022 2 commits
  12. 08 Mar, 2022 1 commit
  13. 01 Mar, 2022 2 commits
    • ranshid's avatar
      Introduce debug command to disable reply buffer resizing (#10360) · 9b15dd28
      ranshid authored
      In order to resolve some flaky tests which hard rely on examine memory footprint.
      we introduce the following fixes:
      
      # Fix in client-eviction test - by @yoav-steinberg 
      Sometime the libc allocator can use different size client struct allocations.
      this may cause unexpected memory calculations to fail the test.
      
      # Introduce new DEBUG command for disabling reply buffer resizing
      In order to eliminate reply buffer resizing during specific tests.
      we introduced the ability to disable (and enable) the resizing cron job
      
      Co-authored-by: yoav-steinberg yoav@redislabs.com
      9b15dd28
    • Madelyn Olson's avatar
      Move most of the configuration to a hashtable (#10323) · 4a45386e
      Madelyn Olson authored
      * Moved configuration storage from a list to a hash table
      * Configs are returned in a non-deterministic order. It's possible that a client was relying on order (hopefully not).
      * Fixed an esoteric bug where if you did a set with an alias with an error, it would throw an error indicating a bug with the preferred name for that config.
      4a45386e
  14. 27 Feb, 2022 1 commit
    • Meir Shpilraien (Spielrein)'s avatar
      Sort out the mess around Lua error messages and error stats (#10329) · aa856b39
      Meir Shpilraien (Spielrein) authored
      
      
      This PR fix 2 issues on Lua scripting:
      * Server error reply statistics (some errors were counted twice).
      * Error code and error strings returning from scripts (error code was missing / misplaced).
      
      ## Statistics
      a Lua script user is considered part of the user application, a sophisticated transaction,
      so we want to count an error even if handled silently by the script, but when it is
      propagated outwards from the script we don't wanna count it twice. on the other hand,
      if the script decides to throw an error on its own (using `redis.error_reply`), we wanna
      count that too.
      Besides, we do count the `calls` in command statistics for the commands the script calls,
      we we should certainly also count `failed_calls`.
      So when a simple `eval "return redis.call('set','x','y')" 0` fails, it should count the failed call
      to both SET and EVAL, but the `errorstats` and `total_error_replies` should be counted only once.
      
      The PR changes the error object that is raised on errors. Instead of raising a simple Lua
      string, Redis will raise a Lua table in the following format:
      
      ```
      {
          err='<error message (including error code)>',
          source='<User source file name>',
          line='<line where the error happned>',
          ignore_error_stats_update=true/false,
      }
      ```
      
      The `luaPushError` function was modified to construct the new error table as describe above.
      The `luaRaiseError` was renamed to `luaError` and is now simply called `lua_error` to raise
      the table on the top of the Lua stack as the error object.
      The reason is that since its functionality is changed, in case some Redis branch / fork uses it,
      it's better to have a compilation error than a bug.
      
      The `source` and `line` fields are enriched by the error handler (if possible) and the
      `ignore_error_stats_update` is optional and if its not present then the default value is `false`.
      If `ignore_error_stats_update` is true, the error will not be counted on the error stats.
      
      When parsing Redis call reply, each error is translated to a Lua table on the format describe
      above and the `ignore_error_stats_update` field is set to `true` so we will not count errors
      twice (we counted this error when we invoke the command).
      
      The changes in this PR might have been considered as a breaking change for users that used
      Lua `pcall` function. Before, the error was a string and now its a table. To keep backward
      comparability the PR override the `pcall` implementation and extract the error message from
      the error table and return it.
      
      Example of the error stats update:
      
      ```
      127.0.0.1:6379> lpush l 1
      (integer) 2
      127.0.0.1:6379> eval "return redis.call('get', 'l')" 0
      (error) WRONGTYPE Operation against a key holding the wrong kind of value. script: e471b73f1ef44774987ab00bdf51f21fd9f7974a, on @user_script:1.
      
      127.0.0.1:6379> info Errorstats
      # Errorstats
      errorstat_WRONGTYPE:count=1
      
      127.0.0.1:6379> info commandstats
      # Commandstats
      cmdstat_eval:calls=1,usec=341,usec_per_call=341.00,rejected_calls=0,failed_calls=1
      cmdstat_info:calls=1,usec=35,usec_per_call=35.00,rejected_calls=0,failed_calls=0
      cmdstat_lpush:calls=1,usec=14,usec_per_call=14.00,rejected_calls=0,failed_calls=0
      cmdstat_get:calls=1,usec=10,usec_per_call=10.00,rejected_calls=0,failed_calls=1
      ```
      
      ## error message
      We can now construct the error message (sent as a reply to the user) from the error table,
      so this solves issues where the error message was malformed and the error code appeared
      in the middle of the error message:
      
      ```diff
      127.0.0.1:6379> eval "return redis.call('set','x','y')" 0
      -(error) ERR Error running script (call to 71e6319f97b0fe8bdfa1c5df3ce4489946dda479): @user_script:1: OOM command not allowed when used memory > 'maxmemory'.
      +(error) OOM command not allowed when used memory > 'maxmemory' @user_script:1. Error running script (call to 71e6319f97b0fe8bdfa1c5df3ce4489946dda479)
      ```
      
      ```diff
      127.0.0.1:6379> eval "redis.call('get', 'l')" 0
      -(error) ERR Error running script (call to f_8a705cfb9fb09515bfe57ca2bd84a5caee2cbbd1): @user_script:1: WRONGTYPE Operation against a key holding the wrong kind of value
      +(error) WRONGTYPE Operation against a key holding the wrong kind of value script: 8a705cfb9fb09515bfe57ca2bd84a5caee2cbbd1, on @user_script:1.
      ```
      
      Notica that `redis.pcall` was not change:
      ```
      127.0.0.1:6379> eval "return redis.pcall('get', 'l')" 0
      (error) WRONGTYPE Operation against a key holding the wrong kind of value
      ```
      
      
      ## other notes
      Notice that Some commands (like GEOADD) changes the cmd variable on the client stats so we
      can not count on it to update the command stats. In order to be able to update those stats correctly
      we needed to promote `realcmd` variable to be located on the client struct.
      
      Tests was added and modified to verify the changes.
      
      Related PR's: #10279, #10218, #10278, #10309
      Co-authored-by: default avatarOran Agra <oran@redislabs.com>
      aa856b39
  15. 23 Feb, 2022 2 commits
    • Itamar Haber's avatar
      Add stream consumer group lag tracking and reporting (#9127) · c81c7f51
      Itamar Haber authored
      
      
      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: default avatarGuy Benoish <guy.benoish@redislabs.com>
      Co-authored-by: default avatarOran Agra <oran@redislabs.com>
      c81c7f51
    • filipe oliveira's avatar
      Optimize deferred replies to use shared objects instead of sprintf (#10334) · b857928b
      filipe oliveira authored
      
      
      Avoid sprintf/ll2string on setDeferredAggregateLen()/addReplyLongLongWithPrefix() when we can used shared objects.
      In some pipelined workloads this achieves about 10% improvement.
      Co-authored-by: default avatarOran Agra <oran@redislabs.com>
      b857928b
  16. 22 Feb, 2022 2 commits
    • ranshid's avatar
      introduce dynamic client reply buffer size - save memory on idle clients (#9822) · 47c51d0c
      ranshid authored
      
      
      Current implementation simple idle client which serves no traffic still
      use ~17Kb of memory. this is mainly due to a fixed size reply buffer
      currently set to 16kb.
      
      We have encountered some cases in which the server operates in a low memory environments.
      In such cases a user who wishes to create large connection pools to support potential burst period,
      will exhaust a large amount of memory  to maintain connected Idle clients.
      Some users may choose to "sacrifice" performance in order to save memory.
      
      This commit introduce a dynamic mechanism to shrink and expend the client reply buffer based on
      periodic observed peak.
      the algorithm works as follows:
      1. each time a client reply buffer has been fully written, the last recorded peak is updated: 
      new peak = MAX( last peak, current written size)
      2. during clients cron we check for each client if the last observed peak was:
           a. matching the current buffer size - in which case we expend (resize) the buffer size by 100%
           b. less than half the buffer size - in which case we shrink the buffer size by 50%
      3. In any case we will **not** resize the buffer in case:
          a. the current buffer peak is less then the current buffer usable size and higher than 1/2 the
            current buffer usable size
          b. the value of (current buffer usable size/2) is less than 1Kib
          c. the value of  (current buffer usable size*2) is larger than 16Kib
      4. the peak value is reset to the current buffer position once every **5** seconds. we maintain a new
         field in the client structure (buf_peak_last_reset_time) which is used to keep track of how long it
         passed since the last buffer peak reset.
      
      ### **Interface changes:**
      **CIENT LIST** - now contains 2 new extra fields:
      rbs= < the current size in bytes of the client reply buffer >
      rbp=< the current value in bytes of the last observed buffer peak position >
      
      **INFO STATS** - now contains 2 new statistics:
      reply_buffer_shrinks = < total number of buffer shrinks performed >
      reply_buffer_expends = < total number of buffer expends performed >
      Co-authored-by: default avatarOran Agra <oran@redislabs.com>
      Co-authored-by: default avatarYoav Steinberg <yoav@redislabs.com>
      47c51d0c
    • Madelyn Olson's avatar
      Implemented module getchannels api and renamed channel keyspec (#10299) · 71204f96
      Madelyn Olson authored
      This implements the following main pieces of functionality:
      * Renames key spec "CHANNEL" to be "NOT_KEY", and update the documentation to
        indicate it's for cluster routing and not for any other key related purpose.
      * Add the getchannels-api, so that modules can now define commands that are subject to
        ACL channel permission checks. 
      * Add 4 new flags that describe how a module interacts with a command (SUBSCRIBE, PUBLISH,
        UNSUBSCRIBE, and PATTERN). They are all technically composable, however not sure how a
        command could both subscribe and unsubscribe from a command at once, but didn't see
        a reason to add explicit validation there.
      * Add two new module apis RM_ChannelAtPosWithFlags and RM_IsChannelsPositionRequest to
        duplicate the functionality provided by the keys position APIs.
      * The RM_ACLCheckChannelPermissions (only released in 7.0 RC1) was changed to take flags
        rather than a boolean literal.
      * The RM_ACLCheckKeyPermissions (only released in 7.0 RC1) was changed to take flags
        corresponding to keyspecs instead of custom permission flags. These keyspec flags mimic
        the flags for ACLCheckChannelPermissions.
      71204f96
  17. 21 Feb, 2022 1 commit
    • Oran Agra's avatar
      Fix error stats and failed command stats for blocked clients (#10309) · fad0b0d2
      Oran Agra authored
      This is a followup work for #10278, and a discussion about #10279
      
      The changes:
      - fix failed_calls in command stats for blocked clients that got error.
        including CLIENT UNBLOCK, and module replying an error from a thread.
      - fix latency stats for XREADGROUP that filed with -NOGROUP
      
      Theory behind which errors should be counted:
      - error stats represents errors returned to the user, so an error handled by a
        module should not be counted.
      - total error counter should be the same.
      - command stats represents execution of commands (even with RM_Call, and if
        they fail or get rejected it counts these calls in commandstats, so it should
        also count failed_calls)
      
      Some thoughts about Scripts:
      for scripts it could be different since they're part of user code, not the infra (not an extension to redis)
      we certainly want commandstats to contain all calls and errors
      a simple script is like mult-exec transaction so an error inside it should be counted in error stats
      a script that replies with an error to the user (using redis.error_reply) should also be counted in error stats
      but then the problem is that a plain `return redis.call("SET")` should not be counted twice (once for the SET
      and once for EVAL)
      so that's something left to be resolved in #10279
      fad0b0d2
  18. 17 Feb, 2022 1 commit
    • yoav-steinberg's avatar
      aof rewrite and rdb save counters in info (#10178) · 56fa48ff
      yoav-steinberg authored
      Add aof_rewrites and rdb_snapshots counters to info.
      This is useful to figure our if a rewrite or snapshot happened since last check.
      This was part of the (ongoing) effort to provide a safe backup solution for multipart-aof backups.
      56fa48ff
  19. 09 Feb, 2022 2 commits
  20. 08 Feb, 2022 2 commits
    • Wen Hui's avatar
      Make INFO command variadic (#6891) · 2e1bc942
      Wen Hui authored
      
      
      This is an enhancement for INFO command, previously INFO only support one argument
      for different info section , if user want to get more categories information, either perform
      INFO all / default or calling INFO for multiple times.
      
      **Description of the feature**
      
      The goal of adding this feature is to let the user retrieve multiple categories via the INFO
      command, and still avoid emitting the same section twice.
      
      A use case for this is like Redis Sentinel, which periodically calling INFO command to refresh
      info from monitored Master/Slaves, only Server and Replication part categories are used for
      parsing information. If the INFO command can return just enough categories that client side
      needs, it can save a lot of time for client side parsing it as well as network bandwidth.
      
      **Implementation**
      To share code between redis, sentinel, and other users of INFO (DEBUG and modules),
      we have a new `genInfoSectionDict` function that returns a dict and some boolean flags
      (e.g. `all`) to the caller (built from user input).
      Sentinel is later purging unwanted sections from that, and then it is forwarded to the info `genRedisInfoString`.
      
      **Usage Examples**
      INFO Server Replication   
      INFO CPU Memory
      INFO default commandstats
      Co-authored-by: default avatarOran Agra <oran@redislabs.com>
      2e1bc942
    • Oran Agra's avatar
      Handle key-spec flags with modules (#10237) · 66be30f7
      Oran Agra authored
      - add COMMAND GETKEYSANDFLAGS sub-command
      - add RM_KeyAtPosWithFlags and GetCommandKeysWithFlags
      - RM_KeyAtPos and RM_CreateCommand set flags requiring full access for keys
      - RM_CreateCommand set VARIABLE_FLAGS
      - expose `variable_flags` flag in COMMAND INFO key-specs
      - getKeysFromCommandWithSpecs prefers key-specs over getkeys-api
      - add tests for all of these
      66be30f7
  21. 07 Feb, 2022 1 commit
    • Binbin's avatar
      COMMAND DOCS avoid adding summary/since if they don't exist (#10252) · 7f4cca11
      Binbin authored
      If summary or since is empty, we used to return NULL in
      COMMAND DOCS. Currently all redis commands will have these
      two fields.
      
      But not for module command, summary and since are optional
      for RM_SetCommandInfo. With the change in #10043, if a module
      command doesn't have the summary or since, redis-cli will
      crash (see #10250).
      
      In this commit, COMMAND DOCS avoid adding summary or since
      when they are missing.
      7f4cca11
  22. 04 Feb, 2022 2 commits
    • Viktor Söderqvist's avatar
      Command info module API (#10108) · 0a82fe84
      Viktor Söderqvist authored
      Adds RM_SetCommandInfo, allowing modules to provide the following command info:
      
      * summary
      * complexity
      * since
      * history
      * hints
      * arity
      * key specs
      * args
      
      This information affects the output of `COMMAND`, `COMMAND INFO` and `COMMAND DOCS`,
      Cluster, ACL and is used to filter commands with the wrong number of arguments before
      the call reaches the module code.
      
      The recently added API functions for key specs (never released) are removed.
      
      A minimalist example would look like so:
      ```c
          RedisModuleCommand *mycmd = RedisModule_GetCommand(ctx,"mymodule.mycommand");
          RedisModuleCommandInfo mycmd_info = {
              .version = REDISMODULE_COMMAND_INFO_VERSION,
              .arity = -5,
              .summary = "some description",
          };
          if (RedisModule_SetCommandInfo(mycmd, &mycmd_info) == REDISMODULE_ERR)
              return REDISMODULE_ERR;
      ````
      
      Notes:
      * All the provided information (including strings) is copied, not keeping references to the API input data.
      * The version field is actually a static struct that contains the sizes of the the structs used in arrays,
        so we can extend these in the future and old version will still be able to take the part they can support.
      0a82fe84
    • Binbin's avatar
      Fix SENTINEL SET config rewrite test (#10232) · d7fcb3c5
      Binbin authored
      Change the sentinel config file to a directory in SENTINEL SET test.
      So it will now fail on the `rename` in `rewriteConfigOverwriteFile`.
      
      The test used to set the sentinel config file permissions to `000` to
      simulate failure. But it fails on centos7 / freebsd / alpine. (introduced in #10151)
      
      Other changes:
      1. More error messages after the config rewrite failure.
      2. Modify arg name `force_all` in `rewriteConfig` to `force_write`. (was rename in #9304)
      3. Fix a typo in debug quicklist-packed-threshold, then -> than. (#9357)
      d7fcb3c5
  23. 30 Jan, 2022 2 commits
    • Moti Cohen's avatar
      Improve srand entropy (and fix Sentinel failures) (#10197) · 52b2fbe9
      Moti Cohen authored
      As Sentinel relies upon consensus algorithm, all sentinel instances,
      randomize a time to initiate their next attempt to become the
      leader of the group. But time after time, all raffled the same value.
      
      The problem is in the line `srand(time(NULL)^getpid())` such that
      all spinned up containers get same time (in seconds) and same pid
      which is always 1. Added material `tv_usec` and verify that even
      consecutive calls brings different values and makes the difference.
      52b2fbe9
    • guybe7's avatar
      Add key-specs notes (#10193) · eedec155
      guybe7 authored
      Add optional `notes` to keyspecs.
      
      Other changes:
      
      1. Remove the "incomplete" flag from SORT and SORT_RO: it is misleading since "incomplete" means "this spec may not return all the keys it describes" but SORT and SORT_RO's specs (except the input key) do not return any keys at all.
      So basically:
      If a spec's begin_search is "unknown" you should not use it at all, you must use COMMAND KEYS;
      if a spec itself is "incomplete", you can use it to get a partial list of keys, but if you want all of them you must use COMMAND GETKEYS;
      otherwise, the spec will return all the keys
      
      2. `getKeysUsingKeySpecs` handles incomplete specs internally
      eedec155
  24. 26 Jan, 2022 1 commit
  25. 24 Jan, 2022 1 commit
    • yoav-steinberg's avatar
      Support function flags in script EVAL via shebang header (#10126) · 7eadc5ee
      yoav-steinberg authored
      In #10025 we added a mechanism for flagging certain properties for Redis Functions.
      This lead us to think we'd like to "port" this mechanism to Redis Scripts (`EVAL`) as well. 
      
      One good reason for this, other than the added functionality is because it addresses the
      poor behavior we currently have in `EVAL` in case the script performs a (non DENY_OOM) write operation
      during OOM state. See #8478 (And a previous attempt to handle it via #10093) for details.
      Note that in Redis Functions **all** write operations (including DEL) will return an error during OOM state
      unless the function is flagged as `allow-oom` in which case no OOM checking is performed at all.
      
      This PR:
      - Enables setting `EVAL` (and `SCRIPT LOAD`) script flags as defined in #10025.
      - Provides a syntactical framework via [shebang](https://en.wikipedia.org/wiki/Shebang_(Unix)) for
        additional script annotations and even engine selection (instead of just lua) for scripts.
      - Provides backwards compatibility so scripts without the new annotations will behave as they did before.
      - Appropriate tests.
      - Changes `EVAL[SHA]/_RO` to be flagged as `STALE` commands. This makes it possible to flag individual
        scripts as `allow-stale` or not flag them as such. In backwards compatibility mode these commands will
        return the `MASTERDOWN` error as before.
      - Changes `SCRIPT LOAD` to be flagged as a `STALE` command. This is mainly to make it logically
        compatible with the change to `EVAL` in the previous point. It enables loading a script on a stale server
        which is technically okay it doesn't relate directly to the server's dataset. Running the script does, but that
        won't work unless the script is explicitly marked as `allow-stale`.
      
      Note that even though the LUA syntax doesn't support hash tag comments `.lua` files do support a shebang
      tag on the top so they can be executed on Unix systems like any shell script. LUA's `luaL_loadfile` handles
      this as part of the LUA library. In the case of `luaL_loadbuffer`, which is what Redis uses, I needed to fix the
      input script in case of a shebang manually. I did this the same way `luaL_loadfile` does, by replacing the
      first line with a single line feed character.
      7eadc5ee
  26. 23 Jan, 2022 1 commit
    • Binbin's avatar
      sub-command support for ACL CAT and COMMAND LIST. redisCommand always stores fullname (#10127) · 23325c13
      Binbin authored
      
      
      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: default avatarOran Agra <oran@redislabs.com>
      Co-authored-by: default avatarguybe7 <guy.benoish@redislabs.com>
      23325c13