Changes:
- When AOF is enabled **after** startup, the data accumulated during `AOF_WAIT_REWRITE`
will only be stored in a temp INCR AOF file. Only after the first AOFRW is successful, we will
add it to manifest file.
Before this fix, the manifest referred to the temp file which could cause a restart during that
time to load it without it's base.
- Add `aof_rewrites_consecutive_failures` info field for aofrw limiting implementation.
Now we can guarantee that these behaviors of MP-AOF are the same as before (past redis releases):
- When AOF is enabled after startup, the data accumulated during `AOF_WAIT_REWRITE` will only
be stored in a visible place. Only after the first AOFRW is successful, we will add it to manifest file.
- When disable AOF, we did not delete the AOF file in the past so there's no need to change that
behavior now (yet).
- When toggling AOF off and then on (could be as part of a full-sync), a crash or restart before the
first rewrite is completed, would result with the previous version being loaded (might not be right thing,
but that's what we always had).
Make sure the status return from loading multiple AOF files reflects the overall
result, not just the one of the last file.
When one of the AOF files succeeded to load, but the last AOF file
was empty, the loadAppendOnlyFiles will return AOF_EMPTY.
This commit changes this behavior, and return AOF_OK in that case.
This can happen for example, when loading old AOF file, and no more commands processed,
the manifest file will include base AOF file with data, and empty incr AOF file.
Co-authored-by: chenyang8094 <chenyang8094@users.noreply.github.com>
Co-authored-by: Oran Agra <oran@redislabs.com>
Modifications of this PR:
1. Support the verification of `Multi Part AOF`, while still maintaining support for the
old-style `AOF/RDB-preamble`. `redis-check-aof` will automatically choose which
mode to use according to the incoming file format.
`Usage: redis-check-aof [--fix|--truncate-to-timestamp $timestamp] <AOF/manifest>`
2. Refactor part of the code to make it easier to understand
3. Currently only supports truncate (`--fix` or `--truncate-to-timestamp`) the last AOF
file (may be `BASE` or `INCR`)
The reasons for 3 above:
- for `--fix`: Only the last AOF may be truncated, this is guaranteed by redis
- for `--truncate-to-timestamp`: Normally, we only have `BASE` + `INCR` files
at most, and `BASE` cannot be truncated(It only contains a timestamp annotation
at the beginning of the file), so only `INCR` can be truncated. If we have a
`BASE+INCR1+INCR2` file (meaning we have an interrupted AOFRW), Only `INCR2`
files can be truncated at this time. If we still insist on truncate `INCR1`, we need to
manually delete `INCR2` and update the manifest file, then re-run `redis-check-aof`
- If we want to support truncate any file, we need to add very complicated code to support
the atomic modification of multiple file deletion and update manifest, I think this is unnecessary
This extends the previous fix (#10049) to address any form of
non-printable or whitespace character (including newlines, quotes,
non-printables, etc.)
Also, removes the limitation on appenddirname, to align with the way
filenames are handled elsewhere in Redis.
Force create a BASE file (use a foreground `rewriteAppendOnlyFile`) when redis starts from an
empty data set and `appendonly` is yes.
The reasoning is that normally, after redis is running for some time, and the AOF has gone though
a few rewrites, there's always a base rdb file. and the scenario where the base file is missing, is
kinda rare (happens only at empty startup), so this change normalizes it.
But more importantly, there are or could be some complex modules that are started with some
configuration, when they create persistence they write that configuration to RDB AUX fields, so
that can can always know with which configuration the persistence file they're loading was
created (could be critical). there is (was) one scenario in which they could load their persisted data,
and that configuration was missing, and this change fixes it.
Add a new module event: REDISMODULE_SUBEVENT_PERSISTENCE_SYNC_AOF_START, similar to
REDISMODULE_SUBEVENT_PERSISTENCE_AOF_START which is async.
Co-authored-by: Oran Agra <oran@redislabs.com>
Implement Multi-Part AOF mechanism to avoid overheads during AOFRW.
Introducing a folder with multiple AOF files tracked by a manifest file.
The main issues with the the original AOFRW mechanism are:
* buffering of commands that are processed during rewrite (consuming a lot of RAM)
* freezes of the main process when the AOFRW completes to drain the remaining part of the buffer and fsync it.
* double disk IO for the data that arrives during AOFRW (had to be written to both the old and new AOF files)
The main modifications of this PR:
1. Remove the AOF rewrite buffer and related code.
2. Divide the AOF into multiple files, they are classified as two types, one is the the `BASE` type,
it represents the full amount of data (Maybe AOF or RDB format) after each AOFRW, there is only
one `BASE` file at most. The second is `INCR` type, may have more than one. They represent the
incremental commands since the last AOFRW.
3. Use a AOF manifest file to record and manage these AOF files mentioned above.
4. The original configuration of `appendfilename` will be the base part of the new file name, for example:
`appendonly.aof.1.base.rdb` and `appendonly.aof.2.incr.aof`
5. Add manifest-related TCL tests, and modified some existing tests that depend on the `appendfilename`
6. Remove the `aof_rewrite_buffer_length` field in info.
7. Add `aof-disable-auto-gc` configuration. By default we're automatically deleting HISTORY type AOFs.
It also gives users the opportunity to preserve the history AOFs. just for testing use now.
8. Add AOFRW limiting measure. When the AOFRW failures reaches the threshold (3 times now),
we will delay the execution of the next AOFRW by 1 minute. If the next AOFRW also fails, it will be
delayed by 2 minutes. The next is 4, 8, 16, the maximum delay is 60 minutes (1 hour). During the limit
period, we can still use the 'bgrewriteaof' command to execute AOFRW immediately.
9. Support upgrade (load) data from old version redis.
10. Add `appenddirname` configuration, as the directory name of the append only files. All AOF files and
manifest file will be placed in this directory.
11. Only the last AOF file (BASE or INCR) can be truncated. Otherwise redis will exit even if
`aof-load-truncated` is enabled.
Co-authored-by: Oran Agra <oran@redislabs.com>
