1. 30 Apr, 2013 1 commit
    • antirez's avatar
      Sentinel: only demote old master into slave under certain conditions. · 70845320
      antirez authored
      We used to always turn a master into a slave if the DEMOTE flag was set,
      as this was a resurrecting master instance.
      
      However the following race condition is possible for a Sentinel that
      got partitioned or internal issues (tilt mode), and was not able to
      refresh the state in the meantime:
      
      1) Sentinel X is running, master is instance "A".
      3) "A" fails, sentinels will promote slave "B" as master.
      2) Sentinel X goes down because of a network partition.
      4) "A" returns available, Sentinels will demote it as a slave.
      5) "B" fails, other Sentinels will promote slave "A" as master.
      6) At this point Sentinel X comes back.
      
      When "X" comes back he thinks that:
      
      "B" is the master.
      "A" is the slave to demote.
      
      We want to avoid that Sentinel "X" will demote "A" into a slave.
      We also want that Sentinel "X" will detect that the conditions changed
      and will reconfigure itself to monitor the right master.
      
      There are two main ways for the Sentinel to reconfigure itself after
      this event:
      
      1) If "B" is reachable and already configured as a slave by other
      sentinels, "X" will perform a redirection to "A".
      2) If there are not the conditions to demote "A", the fact that "A"
      reports to be a master will trigger a failover detection in "X", that
      will end into a reconfiguraiton to monitor "A".
      
      However if the Sentinel was not reachable, its state may not be updated,
      so in case it titled, or was partiitoned from the master instance of the
      slave to demote, the new implementation waits some time (enough to
      guarantee we can detect the new INFO, and new DOWN conditions).
      
      If after some time still there are not the right condiitons to demote
      the instance, the DEMOTE flag is cleared.
      70845320
  2. 29 Apr, 2013 1 commit
  3. 24 Apr, 2013 4 commits
    • antirez's avatar
      Sentinel: always redirect on master->slave transition. · d2ff5ed6
      antirez authored
      Sentinel redirected to the master if the instance changed runid or it
      was the first time we got INFO, and a role change was detected from
      master to slave.
      
      While this is a good idea in case of slave->master, since otherwise we
      could detect a failover without good reasons just after a reboot with a
      slave with a wrong configuration, in the case of master->slave
      transition is much better to always perform the redirection for the
      following reasons:
      
      1) A Sentinel may go down for some time. When it is back online there is
      no other way to understand there was a failover.
      2) Pointing clients to a slave seems to be always the wrong thing to do.
      3) There is no good rationale about handling things differently once an
      instance is rebooted (runid change) in that case.
      d2ff5ed6
    • antirez's avatar
      b06f13e7
    • antirez's avatar
      AOF: sync data on disk every 32MB when rewriting. · 9ca306d8
      antirez authored
      This prevents the kernel from putting too much stuff in the output
      buffers, doing too heavy I/O all at once. So the goal of this commit is
      to split the disk pressure due to the AOF rewrite process into smaller
      spikes.
      
      Please see issue #1019 for more information.
      9ca306d8
    • antirez's avatar
  4. 23 Apr, 2013 1 commit
    • antirez's avatar
      Test: fix RDB test checking file permissions. · e426ea52
      antirez authored
      When the test is executed using the root account, setting the permission
      to 222 does not work as expected, as root can read files with 222
      permission.
      
      Now we skip the test if root is detected.
      
      This fixes issue #1034 and the duplicated #1040 issue.
      
      Thanks to Jan-Erik Rediger (@badboy on Github) for finding a way to reproduce the issue.
      e426ea52
  5. 22 Apr, 2013 2 commits
  6. 19 Apr, 2013 1 commit
  7. 18 Apr, 2013 1 commit
    • antirez's avatar
      Redis/Jemalloc Gitignore were too aggressive. · 0e3baa52
      antirez authored
      Redis gitignore was too aggressive since simply broken.
      
      Jemalloc gitignore was too agressive because it is conceived to just
      keep the files that allow to generate all the rest in development
      environments (so for instance the "configure" file is excluded).
      0e3baa52
  8. 11 Apr, 2013 2 commits
    • antirez's avatar
      redis-cli: raise error on bad command line switch. · 42ba5d37
      antirez authored
      Previously redis-cli never tried to raise an error when an unrecognized
      switch was encountered, as everything after the initial options is to be
      transmitted to the server.
      
      However this is too liberal, as there are no commands starting with "-".
      So the new behavior is to produce an error if there is an unrecognized
      switch starting with "-". This should not break past redis-cli usages
      but should prevent broken options to be silently discarded.
      
      As far the first token not starting with "-" is encountered, all the
      rest is considered to be part of the command, so you cna still use
      strings starting with "-" as values, like in:
      
          redis-cli --port 6380 set foo --my-value
      42ba5d37
    • antirez's avatar
      redis-cli: --latency-history mode implemented. · 0d7b10ee
      antirez authored
      0d7b10ee
  9. 04 Apr, 2013 1 commit
  10. 03 Apr, 2013 1 commit
  11. 02 Apr, 2013 9 commits
  12. 29 Mar, 2013 1 commit
  13. 28 Mar, 2013 7 commits
  14. 27 Mar, 2013 3 commits
  15. 26 Mar, 2013 5 commits
    • antirez's avatar
      TTL / PTTL commands: two bugs fixed. · a452b548
      antirez authored
      This commit fixes two corner cases for the TTL command.
      
      1) When the key was already logically expired (expire time older
      than current time) the command returned -1 instead of -2.
      
      2) When the key was existing and the expire was found to be exactly 0
      (the key was just about to expire), the command reported -1 (that is, no
      expire) instead of a TTL of zero (that is, about to expire).
      a452b548
    • antirez's avatar
      Flag PUBLISH as read-only in the command table. · 10c6195e
      antirez authored
      10c6195e
    • antirez's avatar
      Transactions: propagate MULTI/EXEC only when needed. · 2618101a
      antirez authored
      MULTI/EXEC is now propagated to the AOF / Slaves only once we encounter
      the first command that is not a read-only one inside the transaction.
      
      The old behavior was to always propagate an empty MULTI/EXEC block when
      the transaction was composed just of read only commands, or even
      completely empty. This created two problems:
      
      1) It's a bandwidth waste in the replication link and a space waste
         inside the AOF file.
      
      2) We used to always increment server.dirty to force the propagation of
         the EXEC command, resulting into triggering RDB saves more often
         than needed.
      
      Note: even read-only commands may also trigger writes that will be
      propagated, when we access a key that is found expired and Redis will
      synthesize a DEL operation. However there is no need for this to stay
      inside the transaction itself, but only to be ordered.
      
      So for instance something like:
      
          MULTI
          GET foo
          SET key zap
          EXEC
      
      May be propagated into:
      
          DEL foo
          MULTI
          SET key zap
          EXEC
      
      While the DEL is outside the transaction, the commands are delivered in
      the right order and it is not possible for other commands to be inserted
      between DEL and MULTI.
      2618101a
    • antirez's avatar
      82516e81
    • antirez's avatar
      Transactions: use the propagate() API to propagate MULTI. · d91dfaf6
      antirez authored
      The behavior is the same, but the code is now cleaner and uses the
      proper interface instead of dealing directly with AOF/replication
      functions.
      d91dfaf6