If a key exists in the target node during a migration (BUSYKEY),
the value of the key on both nodes (source and target) will be compared.
If the key has the same value on both keys, the migration will be
automatically retried with the REPLACE argument in order to override
the target's key.
If the key has different values, the behaviour will depend on such
cases:
- In case of 'fix' command, the migration will stop and the user
will be warned to manually check the key(s).
- In other cases (ie. reshard), if the user launched the command
with the --cluster-replace option, the migration will be
retried with the REPLACE argument, elsewhere the migration will
stop and the user will be warned.
When loading data, we call processEventsWhileBlocked
to process events and execute commands.
But if we are loading AOF it's dangerous, because
processCommand would call freeMemoryIfNeeded to evict,
and that will break data consistency, see issue #5686.
Thanks to @soloestoy for discovering this issue in #5667.
This is an alternative fix in order to avoid both cycling the clients
and also disconnecting clients just having valid read-only transactions
pending.
these metrics become negative when RSS is smaller than the used_memory.
This can easily happen when the program allocated a lot of memory and haven't
written to it yet, in which case the kernel doesn't allocate any pages to the process
In MEMORY USAGE command, we count the key argv[2] into usage,
but the argument in command may contains free spaces because of
sdsMakeRoomFor. But the key in db never contains free spaces
because we use sdsdup when dbAdd, so using the real key to
count the usage is more accurate.
If we encounter an unsupported protocol in the "bind" list, don't
ipso-facto consider it a fatal error. We continue to abort startup if
there are no listening sockets at all.
This ensures that the lack of IPv6 support does not prevent Redis from
starting on Debian where we try to bind to the ::1 interface by default
(via "bind 127.0.0.1 ::1"). A machine with IPv6 disabled (such as some
container systems) would simply fail to start Redis after the initiall
call to apt(8).
This is similar to the case for where "bind" is not specified:
https://github.com/antirez/redis/issues/3894
... and was based on the corresponding PR:
https://github.com/antirez/redis/pull/4108
... but also adds EADDRNOTAVAIL to the list of errors to catch which I
believe is missing from there.
This issue was raised in Debian as both <https://bugs.debian.org/900284>
& <https://bugs.debian.org/914354>.