1. 26 Jan, 2016 2 commits
    • antirez's avatar
      Better address udpate strategy when processing gossip sections. · 025f936c
      antirez authored
      The change covers the case where:
      
      1. There is a node we can't reach (in fail or pfail state).
      2. We see a different address for this node, in the gossip section sent
      to us by a node that, instead, is able to talk with the node we cannot
      talk to.
      
      In this case it's a good bet to switch to the address reported by this
      node, since there was an address switch and it is able to talk with the
      node and we are not.
      
      However previosuly this was done in a dangerous way, by initiating an
      handshake. The handshake, using the MEET packet, forces the receiver to
      join our cluster, and this is not a good idea. If the node in question
      really just switched address, but is the same node, it already knows about
      us, so we just need to perform an address update and a reconnection.
      
      So with this commit instead we just update the address of the node,
      release the node link if any, and attempt to reconnect in the next
      clusterCron() cycle.
      
      The commit also improves debugging messages printed by Cluster during
      address or ID switches.
      025f936c
    • antirez's avatar
      5d9a5335
  2. 25 Jan, 2016 15 commits
  3. 19 Jan, 2016 1 commit
  4. 08 Jan, 2016 3 commits
    • antirez's avatar
      Scripting: handle trailing comments. · e50b9a07
      antirez authored
      This fix, provided by Paul Kulchenko (@pkulchenko), allows the Lua
      scripting engine to evaluate statements with a trailing comment like the
      following one:
      
          EVAL "print() --comment" 0
      
      Lua can't parse the above if the string does not end with a newline, so
      now a final newline is always added automatically. This does not change
      the SHA1 of scripts since the SHA1 is computed on the body we pass to
      EVAL, without the other code we add to register the function.
      
      Close #2951.
      e50b9a07
    • antirez's avatar
      Allow MIGRATE to always be called on local keys for open slots. · e9abc944
      antirez authored
      Extend the MIGRATE extra freedom to be able to be called in the context
      of the local slot, anytime there is a slot open in one or the other
      direction (importing or migrating). This is useful for redis-trib to fix
      the cluster when it has in an odd state.
      
      Thix fix allows "redis-trib fix" to make its work in certain cases where
      previously an error was reported.
      e9abc944
    • antirez's avatar
  5. 06 Jan, 2016 1 commit
    • antirez's avatar
      Cluster: don't send -ASK to MIGRATE. · 319a4c04
      antirez authored
      For non existing keys, we don't want to send -ASK redirections to
      MIGRATE, since when moving slots from the migrating node to the
      importing node, we want just to ignore keys that are no longer there.
      They may be expired or deleted between the GETKEYSINSLOT call and the
      MIGRATE call. Otherwise this causes an error during migrations with
      redis-trib (or equivalent cluster management tools).
      319a4c04
  6. 02 Jan, 2016 1 commit
  7. 18 Dec, 2015 10 commits
  8. 17 Dec, 2015 1 commit
    • antirez's avatar
      Fix a race that may lead to the active (slave) client to be freed. · d999f5a6
      antirez authored
      In issue #2948 a crash was reported in processCommand(). Later Oran Agra
      (@oranagra) traced the bug (in private chat) in the following sequence
      of events:
      
      1. Some maxmemory is set.
      2. The slave is the currently active client and is executing PING or
         REPLCONF or whatever a slave can send to its master.
      3. freeMemoryIfNeeded() is called since maxmemory is set.
      4. flushSlavesOutputBuffers() is called by freeMemoryIfNeeded().
      5. During slaves buffers flush, a write error could be encoutered in
         writeToClient() or sendReplyToClient() depending on the version of
         Redis. This will trigger freeClient() against the currently active
         client, so a segmentation fault will likely happen in
         processCommand() immediately after the call to freeMemoryIfNeeded().
      
      There are different possible fixes:
      
      1. Add flags to writeToClient() (recent versions code base) so that
         we can ignore the write errors, and use this flag in
         flushSlavesOutputBuffers(). However this is not simple to do in older
         versions of Redis.
      2. Use freeClientAsync() during write errors. This works but changes the
         current behavior of releasing clients ASAP when possible. Normally
         we write to clients during the normal event loop processing, in the
         writable client, where there is no active client, so no care must be
         taken.
      3. The fix of this commit: to detect that the current client is no
         longer valid. This fix is a bit "ad-hoc", but works across all the
         versions and has the advantage of not changing the remaining
         behavior. Only alters what happens during this race condition,
         hopefully.
      d999f5a6
  9. 15 Dec, 2015 1 commit
  10. 13 Dec, 2015 5 commits
    • antirez's avatar
      Fix 3.0 merge issues with new MIGRATE. · a5d27d39
      antirez authored
      a5d27d39
    • antirez's avatar
      Cluster: redis-trib: use variadic MIGRATE. · ea897338
      antirez authored
      We use the new variadic/pipelined MIGRATE for faster migration.
      Testing is not easy because to see the time it takes for a slot to be
      migrated requires a very large data set, but even with all the overhead
      of migrating multiple slots and to setup them properly, what used to
      take 4 seconds (1 million keys, 200 slots migrated) is now 1.6 which is
      a good improvement. However the improvement can be a lot larger if:
      
      1. We use large datasets where a single slot has many keys.
      2. By moving more than 10 keys per iteration, making this configurable,
         which is planned.
      
      Close #2710
      Close #2711
      ea897338
    • antirez's avatar
      MIGRATE: Fix key extraction for new form. · 170adbf2
      antirez authored
      170adbf2
    • antirez's avatar
      32e940c0
    • antirez's avatar
      MIGRATE: fix replies processing and argument rewriting. · c460458d
      antirez authored
      We need to process replies after errors in order to delete keys
      successfully transferred. Also argument rewriting was fixed since
      it was broken in several ways. Now a fresh argument vector is created
      and set if we are acknowledged of at least one key.
      c460458d