- 06 Jan, 2022 1 commit
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Meir Shpilraien (Spielrein) authored
# Redis Function Libraries This PR implements Redis Functions Libraries as describe on: https://github.com/redis/redis/issues/9906. Libraries purpose is to provide a better code sharing between functions by allowing to create multiple functions in a single command. Functions that were created together can safely share code between each other without worrying about compatibility issues and versioning. Creating a new library is done using 'FUNCTION LOAD' command (full API is described below) This PR introduces a new struct called libraryInfo, libraryInfo holds information about a library: * name - name of the library * engine - engine used to create the library * code - library code * description - library description * functions - the functions exposed by the library When Redis gets the `FUNCTION LOAD` command it creates a new empty libraryInfo. Redis passes the `CODE` to the relevant engine alongside the empty libraryInfo. As a result, the engine will create one or more functions by calling 'libraryCreateFunction'. The new funcion will be added to the newly created libraryInfo. So far Everything is happening locally on the libraryInfo so it is easy to abort the operation (in case of an error) by simply freeing the libraryInfo. After the library info is fully constructed we start the joining phase by which we will join the new library to the other libraries currently exist on Redis. The joining phase make sure there is no function collision and add the library to the librariesCtx (renamed from functionCtx). LibrariesCtx is used all around the code in the exact same way as functionCtx was used (with respect to RDB loading, replicatio, ...). The only difference is that apart from function dictionary (maps function name to functionInfo object), the librariesCtx contains also a libraries dictionary that maps library name to libraryInfo object. ## New API ### FUNCTION LOAD `FUNCTION LOAD <ENGINE> <LIBRARY NAME> [REPLACE] [DESCRIPTION <DESCRIPTION>] <CODE>` Create a new library with the given parameters: * ENGINE - REPLACE Engine name to use to create the library. * LIBRARY NAME - The new library name. * REPLACE - If the library already exists, replace it. * DESCRIPTION - Library description. * CODE - Library code. Return "OK" on success, or error on the following cases: * Library name already taken and REPLACE was not used * Name collision with another existing library (even if replace was uses) * Library registration failed by the engine (usually compilation error) ## Changed API ### FUNCTION LIST `FUNCTION LIST [LIBRARYNAME <LIBRARY NAME PATTERN>] [WITHCODE]` Command was modified to also allow getting libraries code (so `FUNCTION INFO` command is no longer needed and removed). In addition the command gets an option argument, `LIBRARYNAME` allows you to only get libraries that match the given `LIBRARYNAME` pattern. By default, it returns all libraries. ### INFO MEMORY Added number of libraries to `INFO MEMORY` ### Commands flags `DENYOOM` flag was set on `FUNCTION LOAD` and `FUNCTION RESTORE`. We consider those commands as commands that add new data to the dateset (functions are data) and so we want to disallows to run those commands on OOM. ## Removed API * FUNCTION CREATE - Decided on https://github.com/redis/redis/issues/9906 * FUNCTION INFO - Decided on https://github.com/redis/redis/issues/9899 ## Lua engine changes When the Lua engine gets the code given on `FUNCTION LOAD` command, it immediately runs it, we call this run the loading run. Loading run is not a usual script run, it is not possible to invoke any Redis command from within the load run. Instead there is a new API provided by `library` object. The new API's: * `redis.log` - behave the same as `redis.log` * `redis.register_function` - register a new function to the library The loading run purpose is to register functions using the new `redis.register_function` API. Any attempt to use any other API will result in an error. In addition, the load run is has a time limit of 500ms, error is raise on timeout and the entire operation is aborted. ### `redis.register_function` `redis.register_function(<function_name>, <callback>, [<description>])` This new API allows users to register a new function that will be linked to the newly created library. This API can only be called during the load run (see definition above). Any attempt to use it outside of the load run will result in an error. The parameters pass to the API are: * function_name - Function name (must be a Lua string) * callback - Lua function object that will be called when the function is invokes using fcall/fcall_ro * description - Function description, optional (must be a Lua string). ### Example The following example creates a library called `lib` with 2 functions, `f1` and `f1`, returns 1 and 2 respectively: ``` local function f1(keys, args) return 1 end local function f2(keys, args) return 2 end redis.register_function('f1', f1) redis.register_function('f2', f2) ``` Notice: Unlike `eval`, functions inside a library get the KEYS and ARGV as arguments to the functions and not as global. ### Technical Details On the load run we only want the user to be able to call a white list on API's. This way, in the future, if new API's will be added, the new API's will not be available to the load run unless specifically added to this white list. We put the while list on the `library` object and make sure the `library` object is only available to the load run by using [lua_setfenv](https://www.lua.org/manual/5.1/manual.html#lua_setfenv) API. This API allows us to set the `globals` of a function (and all the function it creates). Before starting the load run we create a new fresh Lua table (call it `g`) that only contains the `library` API (we make sure to set global protection on this table just like the general global protection already exists today), then we use [lua_setfenv](https://www.lua.org/manual/5.1/manual.html#lua_setfenv) to set `g` as the global table of the load run. After the load run finished we update `g` metatable and set `__index` and `__newindex` functions to be `_G` (Lua default globals), we also pop out the `library` object as we do not need it anymore. This way, any function that was created on the load run (and will be invoke using `fcall`) will see the default globals as it expected to see them and will not have the `library` API anymore. An important outcome of this new approach is that now we can achieve a distinct global table for each library (it is not yet like that but it is very easy to achieve it now). In the future we can decide to remove global protection because global on different libraries will not collide or we can chose to give different API to different libraries base on some configuration or input. Notice that this technique was meant to prevent errors and was not meant to prevent malicious user from exploit it. For example, the load run can still save the `library` object on some local variable and then using in `fcall` context. To prevent such a malicious use, the C code also make sure it is running in the right context and if not raise an error.
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- 02 Jan, 2022 1 commit
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yoav-steinberg authored
This is needed in order to ease the deployment of functions for ephemeral cases, where user needs to spin up a server with functions pre-loaded. #### Details: * Added `--functions-rdb` option to _redis-cli_. * Functions only rdb via `REPLCONF rdb-filter-only functions`. This is a placeholder for a space separated inclusion filter for the RDB. In the future can be `REPLCONF rdb-filter-only "functions db:3 key-patten:user*"` and a complementing `rdb-filter-exclude` `REPLCONF` can also be added. * Handle "slave requirements" specification to RDB saving code so we can use the same RDB when different slaves express the same requirements (like functions-only) and not share the RDB when their requirements differ. This is currently just a flags `int`, but can be extended to a more complex structure with various filter fields. * make sure to support filters only in diskless replication mode (not to override the persistence file), we do that by forcing diskless (even if disabled by config) other changes: * some refactoring in rdb.c (extract portion of a big function to a sub-function) * rdb_key_save_delay used in AOFRW too * sendChildInfo takes the number of updated keys (incremental, rather than absolute) Co-authored-by:
Oran Agra <oran@redislabs.com>
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- 26 Dec, 2021 1 commit
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Meir Shpilraien (Spielrein) authored
Follow the conclusions to support Functions in redis cluster (#9899) Added 2 new FUNCTION sub-commands: 1. `FUNCTION DUMP` - dump a binary payload representation of all the functions. 2. `FUNCTION RESTORE <PAYLOAD> [FLUSH|APPEND|REPLACE]` - give the binary payload extracted using `FUNCTION DUMP`, restore all the functions on the given payload. Restore policy can be given to control how to handle existing functions (default is APPEND): * FLUSH: delete all existing functions. * APPEND: appends the restored functions to the existing functions. On collision, abort. * REPLACE: appends the restored functions to the existing functions. On collision, replace the old function with the new function. Modify `redis-cli --cluster add-node` to use `FUNCTION DUMP` to get existing functions from one of the nodes in the cluster, and `FUNCTION RESTORE` to load the same set of functions to the new node. `redis-cli` will execute this step before sending the `CLUSTER MEET` command to the new node. If `FUNCTION DUMP` returns an error, assume the current Redis version do not support functions and skip `FUNCTION RESTORE`. If `FUNCTION RESTORE` fails, abort and do not send the `CLUSTER MEET` command. If the new node already contains functions (before the `FUNCTION RESTORE` is sent), abort and do not add the node to the cluster. Test was added to verify `redis-cli --cluster add-node` works as expected.
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- 02 Dec, 2021 1 commit
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meir@redislabs.com authored
Redis function unit is located inside functions.c and contains Redis Function implementation: 1. FUNCTION commands: * FUNCTION CREATE * FCALL * FCALL_RO * FUNCTION DELETE * FUNCTION KILL * FUNCTION INFO 2. Register engine In addition, this commit introduce the first engine that uses the Redis Function capabilities, the Lua engine.
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- 04 Nov, 2021 1 commit
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Eduardo Semprebon authored
For diskless replication in swapdb mode, considering we already spend replica memory having a backup of current db to restore in case of failure, we can have the following benefits by instead swapping database only in case we succeeded in transferring db from master: - Avoid `LOADING` response during failed and successful synchronization for cases where the replica is already up and running with data. - Faster total time of diskless replication, because now we're moving from Transfer + Flush + Load time to Transfer + Load only. Flushing the tempDb is done asynchronously after swapping. - This could be implemented also for disk replication with similar benefits if consumers are willing to spend the extra memory usage. General notes: - The concept of `backupDb` becomes `tempDb` for clarity. - Async loading mode will only kick in if the replica is syncing from a master that has the same repl-id the one it had before. i.e. the data it's getting belongs to a different time of the same timeline. - New property in INFO: `async_loading` to differentiate from the blocking loading - Slot to Key mapping is now a field of `redisDb` as it's more natural to access it from both server.db and the tempDb that is passed around. - Because this is affecting replicas only, we assume that if they are not readonly and write commands during replication, they are lost after SYNC same way as before, but we're still denying CONFIG SET here anyways to avoid complications. Considerations for review: - We have many cases where server.loading flag is used and even though I tried my best, there may be cases where async_loading should be checked as well and cases where it shouldn't (would require very good understanding of whole code) - Several places that had different behavior depending on the loading flag where actually meant to just handle commands coming from the AOF client differently than ones coming from real clients, changed to check CLIENT_ID_AOF instead. **Additional for Release Notes** - Bugfix - server.dirty was not incremented for any kind of diskless replication, as effect it wouldn't contribute on triggering next database SAVE - New flag for RM_GetContextFlags module API: REDISMODULE_CTX_FLAGS_ASYNC_LOADING - Deprecated RedisModuleEvent_ReplBackup. Starting from Redis 7.0, we don't fire this event. Instead, we have the new RedisModuleEvent_ReplAsyncLoad holding 3 sub-events: STARTED, ABORTED and COMPLETED. - New module flag REDISMODULE_OPTIONS_HANDLE_REPL_ASYNC_LOAD for RedisModule_SetModuleOptions to allow modules to declare they support the diskless replication with async loading (when absent, we fall back to disk-based loading). Co-authored-by:
Eduardo Semprebon <edus@saxobank.com> Co-authored-by:
Oran Agra <oran@redislabs.com>
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- 03 Nov, 2021 1 commit
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perryitay authored
Redis lists are stored in quicklist, which is currently a linked list of ziplists. Ziplists are limited to storing elements no larger than 4GB, so when bigger items are added they're getting truncated. This PR changes quicklists so that they're capable of storing large items in quicklist nodes that are plain string buffers rather than ziplist. As part of the PR there were few other changes in redis: 1. new DEBUG sub-commands: - QUICKLIST-PACKED-THRESHOLD - set the threshold of for the node type to be plan or ziplist. default (1GB) - QUICKLIST <key> - Shows low level info about the quicklist encoding of <key> 2. rdb format change: - A new type was added - RDB_TYPE_LIST_QUICKLIST_2 . - container type (packed / plain) was added to the beginning of the rdb object (before the actual node list). 3. testing: - Tests that requires over 100MB will be by default skipped. a new flag was added to 'runtest' to run the large memory tests (not used by default) Co-authored-by:
sundb <sundbcn@gmail.com> Co-authored-by:
Oran Agra <oran@redislabs.com>
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- 03 Oct, 2021 1 commit
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Binbin authored
1. Remove forward declarations from header files to functions that do not exist: hmsetCommand and rdbSaveTime. 2. Minor phrasing fixes in #9519 3. Add missing sdsfree(title) and fix typo in redis-benchmark. 4. Modify some error comments in some zset commands. 5. Fix copy-paste bug comment in syncWithMaster about `ip-address`.
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- 13 Sep, 2021 1 commit
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zhaozhao.zz authored
The main idea is how to allow a master to load replication info from RDB file when rebooting, if master can load replication info it means that replicas may have the chance to psync with master, it can save much traffic. The key point is we need guarantee safety and consistency, so there are two differences between master and replica: 1. master would load the replication info as secondary ID and offset, in case other masters have the same replid. 2. when master loading RDB, it would propagate expired keys as DEL command to replication backlog, then replica can receive these commands to delete stale keys. p.s. the expired keys when RDB loading is useful for users, so we show it as `rdb_last_load_keys_expired` and `rdb_last_load_keys_loaded` in info persistence. Moreover, after load replication info, master should update `no_replica_time` in case loading RDB cost too long time.
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- 09 Sep, 2021 1 commit
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sundb authored
Part two of implementing #8702 (zset), after #8887. ## Description of the feature Replaced all uses of ziplist with listpack in t_zset, and optimized some of the code to optimize performance. ## Rdb format changes New `RDB_TYPE_ZSET_LISTPACK` rdb type. ## Rdb loading improvements: 1) Pre-expansion of dict for validation of duplicate data for listpack and ziplist. 2) Simplifying the release of empty key objects when RDB loading. 3) Unify ziplist and listpack data verify methods for zset and hash, and move code to rdb.c. ## Interface changes 1) New `zset-max-listpack-entries` config is an alias for `zset-max-ziplist-entries` (same with `zset-max-listpack-value`). 2) OBJECT ENCODING will return listpack instead of ziplist. ## Listpack improvements: 1) Add `lpDeleteRange` and `lpDeleteRangeWithEntry` functions to delete a range of entries from listpack. 2) Improve the performance of `lpCompare`, converting from string to integer is faster than converting from integer to string. 3) Replace `snprintf` with `ll2string` to improve performance in converting numbers to strings in `lpGet()`. ## Zset improvements: 1) Improve the performance of `zzlFind` method, use `lpFind` instead of `lpCompare` in a loop. 2) Use `lpDeleteRangeWithEntry` instead of `lpDelete` twice to delete a element of zset. ## Tests 1) Add some unittests for `lpDeleteRange` and `lpDeleteRangeWithEntry` function. 2) Add zset RDB loading test. 3) Add benchmark test for `lpCompare` and `ziplsitCompare`. 4) Add empty listpack zset corrupt dump test.
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- 10 Aug, 2021 1 commit
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sundb authored
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>
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- 05 Aug, 2021 1 commit
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sundb authored
When we load rdb or restore command, if we encounter a length of 0, it will result in the creation of an empty key. This could either be a corrupt payload, or a result of a bug (see #8453 ) This PR mainly fixes the following: 1) When restore command will return `Bad data format` error. 2) When loading RDB, we will silently discard the key. Co-authored-by:
Oran Agra <oran@redislabs.com>
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- 16 Jun, 2021 1 commit
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chenyang8094 authored
Create new module type enhanced callbacks: mem_usage2, free_effort2, unlink2, copy2. These will be given a context point from which the module can obtain the key name and database id. In addition the digest and defrag context can now be used to obtain the key name and database id.
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- 08 Feb, 2021 1 commit
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Huang Zw authored
Fix typo and some out of date comments
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- 22 Sep, 2020 1 commit
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Ariel Shtul authored
redis-check-rdb was unable to parse rdb files containing module aux data. Co-authored-by:
Oran Agra <oran@redislabs.com>
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- 17 Sep, 2020 1 commit
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Wang Yuan authored
We're already using bg_unlink in several places to delete the rdb file in the background, and avoid paying the cost of the deletion from our main thread. This commit uses bg_unlink to remove the temporary rdb file in the background too. However, in case we delete that rdb file just before exiting, we don't actually wait for the background thread or the main thread to delete it, and just let the OS clean up after us. i.e. we open the file, unlink it and exit with the fd still open. Furthermore, rdbRemoveTempFile can be called from a thread and was using snprintf which is not async-signal-safe, we now use ll2string instead.
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- 09 Apr, 2020 3 commits
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antirez authored
Related to #3243.
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antirez authored
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antirez authored
Reloading of the RDB generated by DEBUG POPULATE 5000000 SAVE is now 25% faster. This commit also prepares the ability to have more flexibility when loading stuff from the RDB, since we no longer use dbAdd() but can control exactly how things are added in the database.
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- 30 Jan, 2020 1 commit
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Guy Benoish authored
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- 29 Oct, 2019 1 commit
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Oran Agra authored
* replication hooks: role change, master link status, replica online/offline * persistence hooks: saving, loading, loading progress * misc hooks: cron loop, shutdown, module loaded/unloaded * change the way hooks test work, and add tests for all of the above startLoading() now gets flag indicating what is loaded. stopLoading() now gets an indication of success or failure. adding startSaving() and stopSaving() with similar args and role.
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- 22 Jul, 2019 1 commit
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Oran Agra authored
Other changes: * fix memory leak in error handling of rdb loading of type OBJ_MODULE
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- 17 Jul, 2019 2 commits
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antirez authored
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Oran Agra authored
now that replica can read rdb directly from the socket, it should avoid exiting on short read and instead try to re-sync. this commit tries to have minimal effects on non-diskless rdb reading. and includes a test that tries to trigger this scenario on various read cases.
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- 15 Mar, 2019 1 commit
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Yossi Gottlieb authored
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- 19 Jun, 2018 1 commit
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Oran Agra authored
due to incorrect forward declaration, it didn't provide all arguments. this lead to random value being read from the stack and return of incorrect time, which in this case doesn't matter since no one uses it.
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- 29 May, 2018 2 commits
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antirez authored
The AOF tail of a combined RDB+AOF is based on the premise of applying the AOF commands to the exact state that there was in the server while the RDB was persisted. By expiring keys while loading the RDB file, we change the state, so applying the AOF tail later may change the state. Test case: * Time1: SET a 10 * Time2: EXPIREAT a $time5 * Time3: INCR a * Time4: PERSIT A. Start bgrewiteaof with RDB preamble. The value of a is 11 without expire time. * Time5: Restart redis from the RDB+AOF: consistency violation. Thanks to @soloestoy for providing the patch. Thanks to @trevor211 for the original issue report and the initial fix. Check issue #4950 for more info.
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WuYunlong authored
we add a new slave, and do a failover, eighter by manual or not, other local slaves will delete the expired keys properly.
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- 16 Mar, 2018 2 commits
- 15 Mar, 2018 1 commit
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antirez authored
This is a big win for caching use cases, since on reloading Redis will still have some idea about what is worth to evict and what not. However this only solves part of the problem because the information is only partially propagated to slaves (on write operations). Reads will not affect slaves LFU and LRU counters, so after a failover the eviction decisions are kinda random until keys start to collect some aging/freq info. However since new slaves are initially populated via RDB file transfer, this means that if we spin up a new slave from a master, and perform an immediate manual failover (for instance in order to upgrade the master), the slave will have eviction informations to use for some time. The LFU/LRU info is persisted only if the maxmemory policy is set to one of the relevant type, even if no actual "maxmemory" memory limit is set.
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- 29 Dec, 2017 1 commit
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Oran Agra authored
- protocol parsing (processMultibulkBuffer) was limitted to 32big positions in the buffer readQueryFromClient potential overflow - rioWriteBulkCount used int, although rioWriteBulkString gave it size_t - several places in sds.c that used int for string length or index. - bugfix in RM_SaveAuxField (return was 1 or -1 and not length) - RM_SaveStringBuffer was limitted to 32bit length
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- 01 Dec, 2017 2 commits
- 19 Sep, 2017 1 commit
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antirez authored
This commit attempts to fix a number of bugs reported in #4316. They are related to the way replication info like replication ID, offsets, and currently selected DB in the master client, are stored and loaded by Redis. In order to avoid inconsistencies the changes in this commit try to enforce that: 1. Replication information are only stored when the RDB file is generated by a slave that has a valid 'master' client, so that we can always extract the currently selected DB. 2. When replication informations are persisted in the RDB file, all the info for a successful PSYNC or nothing is persisted. 3. The RDB replication informations are only loaded if the instance is configured as a slave, otherwise a master can start with IDs that relate to a different history of the data set, and stil retain such IDs in the future while receiving unrelated writes.
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- 27 Jun, 2017 1 commit
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antirez authored
The original RDB serialization format was not parsable without the module loaded, becuase the structure was managed only by the module itself. Moreover RDB is a streaming protocol in the sense that it is both produce di an append-only fashion, and is also sometimes directly sent to the socket (in the case of diskless replication). The fact that modules values cannot be parsed without the relevant module loaded is a problem in many ways: RDB checking tools must have loaded modules even for doing things not involving the value at all, like splitting an RDB into N RDBs by key or alike, or just checking the RDB for sanity. In theory module values could be just a blob of data with a prefixed length in order for us to be able to skip it. However prefixing the values with a length would mean one of the following: 1. To be able to write some data at a previous offset. This breaks stremaing. 2. To bufferize values before outputting them. This breaks performances. 3. To have some chunked RDB output format. This breaks simplicity. Moreover, the above solution, still makes module values a totally opaque matter, with the fowllowing problems: 1. The RDB check tool can just skip the value without being able to at least check the general structure. For datasets composed mostly of modules values this means to just check the outer level of the RDB not actually doing any checko on most of the data itself. 2. It is not possible to do any recovering or processing of data for which a module no longer exists in the future, or is unknown. So this commit implements a different solution. The modules RDB serialization API is composed if well defined calls to store integers, floats, doubles or strings. After this commit, the parts generated by the module API have a one-byte prefix for each of the above emitted parts, and there is a final EOF byte as well. So even if we don't know exactly how to interpret a module value, we can always parse it at an high level, check the overall structure, understand the types used to store the information, and easily skip the whole value. The change is backward compatible: older RDB files can be still loaded since the new encoding has a new RDB type: MODULE_2 (of value 7). The commit also implements the ability to check RDB files for sanity taking advantage of the new feature.
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- 09 Nov, 2016 1 commit
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antirez authored
The gist of the changes is that now, partial resynchronizations between slaves and masters (without the need of a full resync with RDB transfer and so forth), work in a number of cases when it was impossible in the past. For instance: 1. When a slave is promoted to mastrer, the slaves of the old master can partially resynchronize with the new master. 2. Chained slalves (slaves of slaves) can be moved to replicate to other slaves or the master itsef, without requiring a full resync. 3. The master itself, after being turned into a slave, is able to partially resynchronize with the new master, when it joins replication again. In order to obtain this, the following main changes were operated: * Slaves also take a replication backlog, not just masters. * Same stream replication for all the slaves and sub slaves. The replication stream is identical from the top level master to its slaves and is also the same from the slaves to their sub-slaves and so forth. This means that if a slave is later promoted to master, it has the same replication backlong, and can partially resynchronize with its slaves (that were previously slaves of the old master). * A given replication history is no longer identified by the `runid` of a Redis node. There is instead a `replication ID` which changes every time the instance has a new history no longer coherent with the past one. So, for example, slaves publish the same replication history of their master, however when they are turned into masters, they publish a new replication ID, but still remember the old ID, so that they are able to partially resynchronize with slaves of the old master (up to a given offset). * The replication protocol was slightly modified so that a new extended +CONTINUE reply from the master is able to inform the slave of a replication ID change. * REPLCONF CAPA is used in order to notify masters that a slave is able to understand the new +CONTINUE reply. * The RDB file was extended with an auxiliary field that is able to select a given DB after loading in the slave, so that the slave can continue receiving the replication stream from the point it was disconnected without requiring the master to insert "SELECT" statements. This is useful in order to guarantee the "same stream" property, because the slave must be able to accumulate an identical backlog. * Slave pings to sub-slaves are now sent in a special form, when the top-level master is disconnected, in order to don't interfer with the replication stream. We just use out of band "\n" bytes as in other parts of the Redis protocol. An old design document is available here: https://gist.github.com/antirez/ae068f95c0d084891305 However the implementation is not identical to the description because during the work to implement it, different changes were needed in order to make things working well.
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- 02 Oct, 2016 1 commit
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antirez authored
When double precision is not needed, to take 2x space in the serialization is not good.
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- 11 Aug, 2016 1 commit
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antirez authored
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- 09 Aug, 2016 1 commit
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antirez authored
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- 03 Jun, 2016 1 commit
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antirez authored
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