1. 21 Dec, 2021 1 commit
    • zhugezy's avatar
      Remove EVAL script verbatim replication, propagation, and deterministic execution logic (#9812) · 1b0968df
      zhugezy authored
      
      
      # Background
      
      The main goal of this PR is to remove relevant logics on Lua script verbatim replication,
      only keeping effects replication logic, which has been set as default since Redis 5.0.
      As a result, Lua in Redis 7.0 would be acting the same as Redis 6.0 with default
      configuration from users' point of view.
      
      There are lots of reasons to remove verbatim replication.
      Antirez has listed some of the benefits in Issue #5292:
      
      >1. No longer need to explain to users side effects into scripts.
          They can do whatever they want.
      >2. No need for a cache about scripts that we sent or not to the slaves.
      >3. No need to sort the output of certain commands inside scripts
          (SMEMBERS and others): this both simplifies and gains speed.
      >4. No need to store scripts inside the RDB file in order to startup correctly.
      >5. No problems about evicting keys during the script execution.
      
      When looking back at Redis 5.0, antirez and core team decided to set the config
      `lua-replicate-commands yes` by default instead of removing verbatim replication
      directly, in case some bad situations happened. 3 years later now before Redis 7.0,
      it's time to remove it formally.
      
      # Changes
      
      - configuration for lua-replicate-commands removed
        - created config file stub for backward compatibility
      - Replication script cache removed
        - this is useless under script effects replication
        - relevant statistics also removed
      - script persistence in RDB files is also removed
      - Propagation of SCRIPT LOAD and SCRIPT FLUSH to replica / AOF removed
      - Deterministic execution logic in scripts removed (i.e. don't run write commands
        after random ones, and sorting output of commands with random order)
        - the flags indicating which commands have non-deterministic results are kept as hints to clients.
      - `redis.replicate_commands()` & `redis.set_repl()` changed
        - now `redis.replicate_commands()` does nothing and return an 1
        - ...and then `redis.set_repl()` can be issued before `redis.replicate_commands()` now
      - Relevant TCL cases adjusted
      - DEBUG lua-always-replicate-commands removed
      
      # Other changes
      - Fix a recent bug comparing CLIENT_ID_AOF to original_client->flags instead of id. (introduced in #9780)
      Co-authored-by: default avatarOran Agra <oran@redislabs.com>
      1b0968df
  2. 05 Aug, 2021 1 commit
    • Binbin's avatar
      Make sure execute SLAVEOF command in the right order in psync2 test. (#9316) · d0244bfc
      Binbin authored
      
      
      The psync2 test has failed several times recently.
      In #9159 we only solved half of the problem.
      i.e. reordering of the replica that's already connected to
      the newly promoted master.
      
      Consider this scenario:
      0 slaveof 2
      1 slaveof 2
      3 slaveof 2
      4 slaveof 1
      0 slaveof no one, became a new master got a new replid
      2 slaveof 0, partial resync and got the new replid
      3 reconnect 2, inherit the new replid
      3 slaveof 4, use the new replid and got a full resync
      
      And another scenario:
      1 slaveof 3
      2 slaveof 4
      3 slaveof 0
      4 slaveof 0
      4 slaveof no one, became a new master got a new replid
      2 reconnect 4, inherit the new replid
      2 slaveof 1, use the new replid and got a full resync
      
      So maybe we should reattach replicas in the right order.
      i.e. In the above example, if it would have reattached 1, 3 and 0 to
      the new chain formed by 4 before trying to attach 2 to 1, it would succeed.
      
      This commit break the SLAVEOF loop into two loops. (ideas from oran)
      
      First loop that uses random to decide who replicates from who.
      Second loop that does the actual SLAVEOF command.
      In the second loop, we make sure to execute it in the right order,
      and after each SLAVEOF, wait for it to be connected before we proceed.
      Co-authored-by: default avatarOran Agra <oran@redislabs.com>
      d0244bfc
  3. 30 Jun, 2021 1 commit
    • Binbin's avatar
      Fix timing issue in psync2 test. (#9159) · 1d5aa37d
      Binbin authored
      
      
      *** [err]: PSYNC2: total sum of full synchronizations is exactly 4 intests/integration/psync2.tcl
      Expected 5 == 4 (context: type eval line 8 cmd {assert {$sum == 4}} proc::test)
      
      Sometime the test got an unexpected full sync since a replica switch to master,
      before the new master change propagated the new replid to all replicas,
      a replica attempted to sync with it using a wrong replid and triggered a full resync.
      
      Consider this scenario:
          1 slaveof 4 full resync
          0 slaveof 4 full resync
          2 slaveof 0 full resync
          3 slaveof 1 full resync
      
          1 slaveof no one, replid changed
          3 reconnect 1, did a partial resyn and got the new replid
      
          Before 2 inherits the new replid.
          3 slaveof 2
          3 try to do a partial resyn with 2.
          But their replication ids are inconsistent, so a full resync happens.
      
      :) A special thank you for oran and helping me in this test case.
      Co-authored-by: default avatarOran Agra <oran@redislabs.com>
      1d5aa37d
  4. 10 Jun, 2021 1 commit
    • Binbin's avatar
      Fixed some typos, add a spell check ci and others minor fix (#8890) · 0bfccc55
      Binbin authored
      This PR adds a spell checker CI action that will fail future PRs if they introduce typos and spelling mistakes.
      This spell checker is based on blacklist of common spelling mistakes, so it will not catch everything,
      but at least it is also unlikely to cause false positives.
      
      Besides that, the PR also fixes many spelling mistakes and types, not all are a result of the spell checker we use.
      
      Here's a summary of other changes:
      1. Scanned the entire source code and fixes all sorts of typos and spelling mistakes (including missing or extra spaces).
      2. Outdated function / variable / argument names in comments
      3. Fix outdated keyspace masks error log when we check `config.notify-keyspace-events` in loadServerConfigFromString.
      4. Trim the white space at the end of line in `module.c`. Check: https://github.com/redis/redis/pull/7751
      5. Some outdated https link URLs.
      6. Fix some outdated comment. Such as:
          - In README: about the rdb, we used to said create a `thread`, change to `process`
          - dbRandomKey function coment (about the dictGetRandomKey, change to dictGetFairRandomKey)
          - notifyKeyspaceEvent fucntion comment (add type arg)
          - Some others minor fix in comment (Most of them are incorrectly quoted by variable names)
      7. Modified the error log so that users can easily distinguish between TCP and TLS in `changeBindAddr`
      0bfccc55
  5. 09 Jun, 2021 1 commit
    • Yossi Gottlieb's avatar
      Improve test suite to handle external servers better. (#9033) · 8a86bca5
      Yossi Gottlieb authored
      This commit revives the improves the ability to run the test suite against
      external servers, instead of launching and managing `redis-server` processes as
      part of the test fixture.
      
      This capability existed in the past, using the `--host` and `--port` options.
      However, it was quite limited and mostly useful when running a specific tests.
      Attempting to run larger chunks of the test suite experienced many issues:
      
      * Many tests depend on being able to start and control `redis-server` themselves,
      and there's no clear distinction between external server compatible and other
      tests.
      * Cluster mode is not supported (resulting with `CROSSSLOT` errors).
      
      This PR cleans up many things and makes it possible to run the entire test suite
      against an external server. It also provides more fine grained controls to
      handle cases where the external server supports a subset of the Redis commands,
      limited number of databases, cluster mode, etc.
      
      The tests directory now contains a `README.md` file that describes how this
      works.
      
      This commit also includes additional cleanups and fixes:
      
      * Tests can now be tagged.
      * Tag-based selection is now unified across `start_server`, `tags` and `test`.
      * More information is provided about skipped or ignored tests.
      * Repeated patterns in tests have been extracted to common procedures, both at a
        global level and on a per-test file basis.
      * Cleaned up some cases where test setup was based on a previous test executing
        (a major anti-pattern that repeats itself in many places).
      * Cleaned up some cases where test teardown was not part of a test (in the
        future we should have dedicated teardown code that executes even when tests
        fail).
      * Fixed some tests that were flaky running on external servers.
      8a86bca5
  6. 06 Dec, 2020 1 commit
    • Oran Agra's avatar
      Sanitize dump payload: fuzz tester and fixes for segfaults and leaks it exposed · c31055db
      Oran Agra authored
      The test creates keys with various encodings, DUMP them, corrupt the payload
      and RESTORES it.
      It utilizes the recently added use-exit-on-panic config to distinguish between
       asserts and segfaults.
      If the restore succeeds, it runs random commands on the key to attempt to
      trigger a crash.
      
      It runs in two modes, one with deep sanitation enabled and one without.
      In the first one we don't expect any assertions or segfaults, in the second one
      we expect assertions, but no segfaults.
      We also check for leaks and invalid reads using valgrind, and if we find them
      we print the commands that lead to that issue.
      
      Changes in the code (other than the test):
      - Replace a few NPD (null pointer deference) flows and division by zero with an
        assertion, so that it doesn't fail the test. (since we set the server to use
        `exit` rather than `abort` on assertion).
      - Fix quite a lot of flows in rdb.c that could have lead to memory leaks in
        RESTORE command (since it now responds with an error rather than panic)
      - Add a DEBUG flag for SET-SKIP-CHECKSUM-VALIDATION so that the test don't need
        to bother with faking a valid checksum
      - Remove a pile of code in serverLogObjectDebugInfo which is actually unsafe to
        run in the crash report (see comments in the code)
      - fix a missing boundary check in lzf_decompress
      
      test suite infra improvements:
      - be able to run valgrind checks before the process terminates
      - rotate log files when restarting servers
      c31055db
  7. 10 Jul, 2020 1 commit
    • Oran Agra's avatar
      tests/valgrind: don't use debug restart (#7404) · 69ade873
      Oran Agra authored
      * tests/valgrind: don't use debug restart
      
      DEBUG REATART causes two issues:
      1. it uses execve which replaces the original process and valgrind doesn't
         have a chance to check for errors, so leaks go unreported.
      2. valgrind report invalid calls to close() which we're unable to resolve.
      
      So now the tests use restart_server mechanism in the tests, that terminates
      the old server and starts a new one, new PID, but same stdout, stderr.
      
      since the stderr can contain two or more valgrind report, it is not enough
      to just check for the absence of leaks, we also need to check for some known
      errors, we do both, and fail if we either find an error, or can't find a
      report saying there are no leaks.
      
      other changes:
      - when killing a server that was already terminated we check for leaks too.
      - adding DEBUG LEAK which was used to test it.
      - adding --trace-children to valgrind, although no longer needed.
      - since the stdout contains two or more runs, we need slightly different way
        of checking if the new process is up (explicitly looking for the new PID)
      - move the code that handles --wait-server to happen earlier (before
        watching the startup message in the log), and serve the restarted server too.
      
      * squashme - CR fixes
      69ade873
  8. 28 May, 2020 1 commit
  9. 27 May, 2020 1 commit
  10. 25 May, 2020 1 commit
  11. 17 May, 2020 1 commit
  12. 28 Apr, 2020 1 commit
  13. 27 Apr, 2020 1 commit
    • Oran Agra's avatar
      Keep track of meaningful replication offset in replicas too · 4447ddc8
      Oran Agra authored
      Now both master and replicas keep track of the last replication offset
      that contains meaningful data (ignoring the tailing pings), and both
      trim that tail from the replication backlog, and the offset with which
      they try to use for psync.
      
      the implication is that if someone missed some pings, or even have
      excessive pings that the promoted replica has, it'll still be able to
      psync (avoid full sync).
      
      the downside (which was already committed) is that replicas running old
      code may fail to psync, since the promoted replica trims pings form it's
      backlog.
      
      This commit adds a test that reproduces several cases of promotions and
      demotions with stale and non-stale pings
      
      Background:
      The mearningful offset on the master was added recently to solve a problem were
      the master is left all alone, injecting PINGs into it's backlog when no one is
      listening and then gets demoted and tries to replicate from a replica that didn't
      have any of the PINGs (or at least not the last ones).
      
      however, consider this case:
      master A has two replicas (B and C) replicating directly from it.
      there's no traffic at all, and also no network issues, just many pings in the
      tail of the backlog. now B gets promoted, A becomes a replica of B, and C
      remains a replica of A. when A gets demoted, it trims the pings from its
      backlog, and successfully replicate from B. however, C is still aware of
      these PINGs, when it'll disconnect and re-connect to A, it'll ask for something
      that's not in the backlog anymore (since A trimmed the tail of it's backlog),
      and be forced to do a full sync (something it didn't have to do before the
      meaningful offset fix).
      
      Besides that, the psync2 test was always failing randomly here and there, it
      turns out the reason were PINGs. Investigating it shows the following scenario:
      
      cycle 1: redis #1 is master, and all the rest are direct replicas of #1
      cycle 2: redis #2 is promoted to master, #1 is a replica of #2 and #3 is replica of #1
      now we see that when #1 is demoted it prints:
      17339:S 21 Apr 2020 11:16:38.523 * Using the meaningful offset 3929963 instead of 3929977 to exclude the final PINGs (14 bytes difference)
      17339:S 21 Apr 2020 11:16:39.391 * Trying a partial resynchronization (request e2b3f8817735fdfe5fa4626766daa938b61419e5:3929964).
      17339:S 21 Apr 2020 11:16:39.392 * Successful partial resynchronization with master.
      and when #3 connects to the demoted #2, #2 says:
      17339:S 21 Apr 2020 11:16:40.084 * Partial resynchronization not accepted: Requested offset for secondary ID was 3929978, but I can reply up to 3929964
      
      so the issue here is that the meaningful offset feature saved the day for the
      demoted master (since it needs to sync from a replica that didn't get the last
      ping), but it didn't help one of the other replicas which did get the last ping.
      4447ddc8
  14. 05 Mar, 2020 1 commit
    • Oran Agra's avatar
      fix for flaky psync2 test · 27641ee4
      Oran Agra authored
      *** [err]: PSYNC2: total sum of full synchronizations is exactly 4 in tests/integration/psync2.tcl
      Expected 5 == 4 (context: type eval line 6 cmd {assert {$sum == 4}} proc ::test)
      
      issue was that sometime the test got an unexpected full sync since it
      tried to switch to the replica before it was in sync with it's master.
      27641ee4
  15. 05 May, 2019 1 commit
    • Oran Agra's avatar
      make replication tests more stable on slow machines · ba809f26
      Oran Agra authored
      solving few replication related tests race conditions which fail on slow machines
      
      bugfix in slave buffers test: since the test is executed twice, each time with
      a different commands count, the threshold for the delta can't be a constant.
      ba809f26
  16. 11 Sep, 2018 1 commit
  17. 31 Jul, 2018 1 commit
  18. 30 Nov, 2017 1 commit
  19. 29 Nov, 2016 3 commits
  20. 28 Nov, 2016 2 commits
    • antirez's avatar
      PSYNC2: stop sending newlines to sub-slaves when master is down. · eab865a0
      antirez authored
      This actually includes two changes:
      
      1) No newlines to take the master-slave link up when the upstream master
      is down. Doing this is dangerous because the sub-slave often is received
      replication protocol for an half-command, so can't receive newlines
      without desyncing the replication link, even with the code in order to
      cancel out the bytes that PSYNC2 was using. Moreover this is probably
      also not needed/sane, because anyway the slave can keep serving
      requests, and because if it's configured to don't serve stale data, it's
      a good idea, actually, to break the link.
      
      2) When a +CONTINUE with a different ID is received, we now break
      connection with the sub-slaves: they need to be notified as well. This
      was part of the original specification but for some reason it was not
      implemented in the code, and was alter found as a PSYNC2 bug in the
      integration testing.
      eab865a0
    • antirez's avatar
      PSYNC2: Test (WIP). · 16559a02
      antirez authored
      This is the PSYNC2 test that helped find issues in the code, and that
      still can show a protocol desync from time to time. Work is in progress
      in order to find the issue. For now the test is not enabled in "make
      test" and must be run manually.
      16559a02