The fs.MustWriteSync() already fsyncs the created file, so there is no need in additional fsync() call.
While at it, add missing fsync for the parent directory after creating a directory for persistent queue.
- Drop the code needed for asynchronous removal of the directory on NFS shares.
This code was needed when VictoriaMetrics could keep open files after their deletion
or renaming. This is no longer the case after the commit 43b24164ef .
Now files are deleted only after all the readers close them.
This updates https://github.com/VictoriaMetrics/VictoriaMetrics/issues/61
- Unify MustRemoveAll() and MustRemoveDirAtomic() into MustRemoveDir() and MustRemovePath()
functions:
- The MustRemoveDir() deletes the given directory with all its contents, in an "atomic" way:
it creates a special `.delete-this-dir` file in the directory, then removes all its contents
except of this file, and later removes the `.delete-this-dir` file together with the directory
itself. This makes possible easily determining whether the given directory needs to be deleted
after unclean shutdown - if it contains the `.delete-this-dir` file or if it is empty, it must be deleted.
Add IsPartiallyRemovedDir() function, which can be used for detecting whether the given directory must be removed
at starup.
Previously the MustRemoveDirAtomic() was using a "trick" for atomic directory removal: it was "atomically" renaming
the directory to a temporary directory with '.must-remove.' marker in the directory name, and after that it
was removing the renamed directory. On startup all the directories with the `.must-remove.` marker were deleted
if they are left after unclean shutdown. This "trick" doesn't work for NFS and object storage such as S3,
since these storage systems do not support atomic renaming of directories with multiple entries inside.
The new MustRemoveDir() function doesn't use this "trick", so it can be safely used in NFS and S3-like storage systems.
This is based on the pull request from @func25 - https://github.com/VictoriaMetrics/VictoriaMetrics/pull/9486/files .
- The MustRemovePath() deletes the given file or an empty directory.
- Delete the existing parts and partitions at startup if they were partially deleted.
- Consistently use fs.MustRemoveDir() and fs.MustRemovePath() instead of os.RemoveAll() across the codebase.
This reduces the amounts of bolierplate code related to error handling.
- Consistently use fs.MustWriteSync() instead of os.WriteFile() across the codebase.
Previously, if the command-line flag value `-remoteWrite.showURL` changed, vmagent dropped content of persistent queues. It's not expected behavior and may lead to data-loss at queue.
Further more if command-line flag value `-remoteWrite.showURL` is set to `true`, any changes to url query arguments will lead to persistent queue drop. The most common uses is kafka and gcp pub-sub integration. It uses url query arguments for client configuration.
Also, it complicates copy content of persistent queue between vmagents. Since it requires to properly change name inside metainfo.json.
This commit removes persistent queue name equality check from `lib/persistentqueue`. This check was added as an additional protection from on-disk data corruption.
It's safe to skip this check for vmagent, because vmagent encodes remoteWrite.url as part of path to the queue. It guarantees that there will be no collision.
related issue:
https://github.com/VictoriaMetrics/VictoriaMetrics/issues/8477.
### Checklist
The following checks are **mandatory**:
- [x] My change adheres [VictoriaMetrics contributing
guidelines](https://docs.victoriametrics.com/contributing/).
---------
Signed-off-by: f41gh7 <nik@victoriametrics.com>
Co-authored-by: f41gh7 <nik@victoriametrics.com>
* app/vmagent,lib/persistentqueue: show warning message if `--remoteWrite.maxDiskUsagePerURL` flag lower than 500MB
* app/vmagent,lib/persistentqueue: linter fix
* app/vmagent,lib/persistentqueue: fix comment
Use fs.MustReadDir() instead of os.ReadDir() across the code in order to reduce the code verbosity.
The fs.MustReadDir() logs the error with the directory name and the call stack on error
before exit. This information should be enough for debugging the cause of the error.
Callers of CreateFlockFile log the returned err and exit.
It is better to log the error inside the MustCreateFlockFile together with the path
to the specified directory and the call stack. This simplifies
the code at the callers' side while leaving the debuggability at the same level.
Callers of this function log the returned error and exit.
It is better logging the error together with the path to the filename
and call stack directly inside the function. This simplifies
the code at callers' side without reducing the level of debuggability
Callers of this function log the returned error and exit.
Let's log the error with the path to the filename and call stack
inside the function. This simplifies the code at callers' side
without reducing the level of debuggability.
Callers of this function log the returned error and exit.
So let's just log the error with the given filepath and the call stack
inside the function itself and then exit. This simplifies the code
at callers' place while leaves the same level of debuggability in case of errors.
Callers of these functions log the returned error and then exit. The returned error already contains the path
to directory, which was failed to be created. So let's just log the error together with the call stack
inside these functions. This leaves the debuggability of the returned error at the same level
while allows simplifying the code at callers' side.
While at it, properly use MustMkdirFailIfExist instead of MustMkdirIfNotExist inside inmemoryPart.MustStoreToDisk().
It is expected that the inmemoryPart.MustStoreToDick() must fail if there is already a directory under the given path.
This fixes handling of values bigger than 2GiB for the following command-line flags:
- -storage.minFreeDiskSpaceBytes
- -remoteWrite.maxDiskUsagePerURL
The ioutil.ReadDir is deprecated since Go1.16 - see https://tip.golang.org/doc/go1.16#ioutil
VictoriaMetrics requires at least Go1.18, so it is time to switch from io.ReadDir to os.ReadDir
This is a follow-up for 02ca2342ab
The ioutil.{Read|Write}File is deprecated since Go1.16 -
see https://tip.golang.org/doc/go1.16#ioutil
VictoriaMetrics needs at least Go1.18, so it is safe to remove ioutil usage
from source code.
This is a follow-up for 02ca2342ab
Previously bytesutil.Resize() was copying the original byte slice contents to a newly allocated slice.
This wasted CPU cycles and memory bandwidth in some places, where the original slice contents wasn't needed
after slize resizing. Switch such places to bytesutil.ResizeNoCopy().
Rename the original bytesutil.Resize() function to bytesutil.ResizeWithCopy() for the sake of improved readability.
Additionally, allocate new slice with `make()` instead of `append()`. This guarantees that the capacity of the allocated slice
exactly matches the requested size. The `append()` could return a slice with bigger capacity as an optimization for further `append()` calls.
This could result in excess memory usage when the returned byte slice was cached (for instance, in lib/blockcache).
Updates https://github.com/VictoriaMetrics/VictoriaMetrics/issues/2007
The strategy is:
- Periodical flushing of inmemory blocks to files, so they aren't lost on unclean shutdown.
- Periodical syncing of metadata for persisted queues, so the metadata remains in sync with the persisted data.
- Automatic adjusting of too big chunk size when opening the queue. The chunk size may be bigger than the writer offset after unclean shutdown.
- Skipping of broken chunk file if it cannot be read.
- Fsyncing finalized chunk files.
Updates https://github.com/VictoriaMetrics/VictoriaMetrics/issues/687
Metric `vm_persistentqueue_bytes_pending` is a gauge that shows current amount
of bytes in persistentqueue flushed on disk as a difference between write and read
offsets. This metric is very similar to `vmagent_remotewrite_pending_data_bytes`
except of accounting for bytes in-memory.
