RESTORE now supports:
1. Setting LRU/LFU
2. Absolute-time TTL
Other related changes:
1. RDB loading will not override LRU bits when RDB file
does not contain the LRU opcode.
2. RDB loading will not set LRU/LFU bits if the server's
maxmemory-policy does not match.
This commit, in some parts derived from PR #3041 which is no longer
possible to merge (because the user deleted the original branch),
implements the ability of slaves to have a special configuration
preventing that they try to start a failover when the master is failing.
There are multiple reasons for wanting this, and the feautre was
requested in issue #3021 time ago.
The differences between this patch and the original PR are the
following:
1. The flag is saved/loaded on the nodes configuration.
2. The 'myself' node is now flag-aware, the flag is updated as needed
when the configuration is changed via CONFIG SET.
3. The flag name uses NOFAILOVER instead of NO_FAILOVER to be consistent
with existing NOADDR.
4. The redis.conf documentation was rewritten.
Thanks to @deep011 for the original patch.
Add AE_BARRIER to the writable event loop so that slaves requesting
votes can't be served before we re-enter the event loop in the next
iteration, so clusterBeforeSleep() will fsync to disk in time.
Also add the call to explicitly fsync, given that we modified the last
vote epoch variable.
The main change introduced by this commit is pretending that help
arrays are more text than code, thus indenting them at level 0. This
improves readability, and is an old practice when defining arrays of
C strings describing text.
Additionally a few useless return statements are removed, and the HELP
subcommand capitalized when printed to the user.
There was not enough sanity checking in the code loading the slots of
Redis Cluster from the nodes.conf file, this resulted into the
attacker's ability to write data at random addresses in the process
memory, by manipulating the index of the array. The bug seems
exploitable using the following techique: the config file may be altered so
that one of the nodes gets, as node ID (which is the first field inside the
structure) some data that is actually executable: then by writing this
address in selected places, this node ID part can be executed after a
jump. So it is mostly just a matter of effort in order to exploit the
bug. In practice however the issue is not very critical because the
bug requires an unprivileged user to be able to modify the Redis cluster
nodes configuration, and at the same time this should result in some
gain. However Redis normally is unprivileged as well. Yet much better to
have this fixed indeed.
Fix#4278.
This function failed when an internal-only flag was set as an only flag
in a node: the string was trimmed expecting a final comma before
exiting the function, causing a crash. See issue #4142.
Moreover generation of flags representation only needed at DEBUG log
level was always performed: a waste of CPU time. This is fixed as well
by this commit.
