Commit Graph

742 Commits

Author SHA1 Message Date
Aliaksandr Valialkin
9183a439c7
lib/filestream: change Create() to MustCreate()
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
2023-04-14 15:12:48 -07:00
Aliaksandr Valialkin
5eb163a08a
lib/filestream: transform Open() -> MustOpen()
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.
2023-04-14 15:03:42 -07:00
Aliaksandr Valialkin
f341b7b3f8
lib/fs: substitute ReadFullData with MustReadData
Callers of ReadFullData() log the error and then exit.
So let's log the error with the path to the filename and the call stack
inside MustReadData(). This simplifies the code at callers' side,
while leaving the debuggability at the same level.
2023-04-14 14:39:29 -07:00
Aliaksandr Valialkin
bd6de6406a
lib/fs: improve error logging inside MustWriteData
Log the path to file on errors inside MustWriteData().
This improves debuggability of errors, which may occur inside MustWriteData().
2023-04-14 14:32:45 -07:00
Aliaksandr Valialkin
e0595af2bf
lib/{mergeset,storage}: remove isInMerge flag from parts only when they werent removed yet from the list of active parts
This prevents from possible panic during access to pw.p when it is set to nil at partWrapper.decRef() called inside swapSrcWithDstParts()
2023-04-14 00:08:11 -07:00
Aliaksandr Valialkin
9f8209d593
docs/CHANGELOG.md: run at least 4 background mergers on systems with less than 4 CPU cores
This reduces the probability of sudden spike in the number of small parts when all the background mergers
are busy with big merges.
2023-04-13 23:43:17 -07:00
Aliaksandr Valialkin
550d5c7ea4
lib/{mergeset,storage}: make sure that getFlushToDiskDeadline() takes into account only in-memory parts 2023-04-13 23:43:17 -07:00
Aliaksandr Valialkin
809fbaeaac
lib/fs: add Must prefix to CopyDirectory and CopyFile functions
Callers of these functions log the returned error and then exit.
Let's log the error with the call stack inside the function itself.
This simplifies the code at callers' side, while leaving the same
level of debuggability in case of errors.
2023-04-13 23:02:59 -07:00
Aliaksandr Valialkin
780abc3b3b
lib/fs: rename SymlinkRelative to MustSymlinkRelative
Callers of this function log the returned error and then exit.
Let's log the error with the call stack inside the function itself.
This simplifies the code at callers' side, while leaving the same
level of debuggability in case of errors.
2023-04-13 22:52:55 -07:00
Aliaksandr Valialkin
5f487ed996
lib/fs: rename HardLinkFiles to MustHardLinkFiles
Callers of this function log the returned error and then exit.
Let's log the error with the call stack inside the function itself.
This simplifies the code at callers' side, while leaving the same
level of debuggability in case of errors.
2023-04-13 22:48:07 -07:00
Aliaksandr Valialkin
30425ca81a
lib/fs: rename WriteFileAtomically to MustWriteAtomic
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.
2023-04-13 22:41:15 -07:00
Aliaksandr Valialkin
036a7b7365
lib/fs: replace MkdirAllIfNotExist->MustMkdirIfNotExist and MkdirAllFailIfExist->MustMkdirFailIfExist
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.
2023-04-13 22:11:59 -07:00
Aliaksandr Valialkin
344209e5e6
lib/fs: rename MustWriteFileAndSync to MustWriteSync in order to improve readability a bit
This is a follow-up for 2a8395be05
2023-04-13 21:43:32 -07:00
Aliaksandr Valialkin
b15c5961ab
lib/{mergeset,storage}: remove unused path field from blockStreamWriter
This is a follow-up after 42bba64aa7
2023-04-13 21:39:59 -07:00
Aliaksandr Valialkin
2a8395be05
lib/fs: replace WriteFileAndSync with MustWriteAndSync
When WriteFileAndSync fails, then the caller eventually logs the error message
and exits. The error message returned by WriteFileAndSync already contains the path
to the file, which couldn't be created. This information alongside the call stack
is enough for debugging the issue. So just use log.Panicf("FATAL: ...") inside MustWriteAndSync().
This simplifies error handling at caller side a bit.
2023-04-13 21:33:19 -07:00
Aliaksandr Valialkin
25f089de9d
lib/{mergeset,storage}: properly fsync part directory listing after writing in-memory part to disk
This is a follow-up after 42bba64aa7

Previously the part directory listing was fsync'ed implicitly inside partHeader.WriteMetadata()
by calling fs.WriteFileAtomically(). Now it must be fsync'ed explicitly.

There is no need in fsync'ing the parent directory, since it is fsync'ed by the caller
when updating parts.json file.
2023-04-13 21:19:04 -07:00
Aliaksandr Valialkin
42bba64aa7
lib/{mergeset,storage}: explicitly fsync the created part directory listing
Previously the created part directory listing was fsynced implicitly
when storing metadata.json file in it.

Also remove superflouous fsync for part directory listing,
which was called at blockStreamWriter.MustClose().
After that the metadata.json file is created, so an additional fsync
for the directory contents is needed.
2023-04-13 21:03:08 -07:00
Aliaksandr Valialkin
e1211a1187
app/vmstorage: deprecate -bigMergeConcurrency command-line flag
Improperly configured -bigMergeConcurrency command-line flag usually leads to uncontrolled
growth of unmerged parts, which, in turn, increases CPU usage and query durations.

So it is better deprecating this flag. In rare cases -smallMergeConcurrency command-line flag
can be used instead for controlling the concurrency of background merges.
2023-04-13 20:40:24 -07:00
Haleygo
0ad6010c91
fix sort pendingDateMetricsIDs (#4102) 2023-04-10 10:23:12 -07:00
Aliaksandr Valialkin
19b189e9b7
lib/storage: use shorter code after 03bde173b7 2023-04-02 21:35:52 -07:00
faceair
38fc55976e
lib/storage: fix reuse pendingMetricRow (#4049) 2023-04-02 21:35:50 -07:00
faceair
f3af8331ec
lib/storage: remove unused code (#4050) 2023-04-02 21:24:42 -07:00
Roman Khavronenko
27b958ba8b
lib/storage: check for free disk space before opening tables (#4035)
* lib/storage: check for free disk space before opening tables

We check for free disk space before call to `openTable`,
so `Storage` can be set to ReadOnly before mergeWorkers start.

Before the change, there was a chance that merges will start
even if Storage has to start in ReadOnly mode because of
`-storage.minFreeDiskSpaceBytes` limit.

https://github.com/VictoriaMetrics/VictoriaMetrics/issues/4023
Signed-off-by: hagen1778 <roman@victoriametrics.com>

* lib/storage: chore

Signed-off-by: hagen1778 <roman@victoriametrics.com>

* Update lib/storage/storage.go

---------

Signed-off-by: hagen1778 <roman@victoriametrics.com>
Co-authored-by: Aliaksandr Valialkin <valyala@victoriametrics.com>
2023-03-31 23:50:27 -07:00
Aliaksandr Valialkin
c8f2febaa1
lib/storage: consistently use OS-independent separator in file paths
This is needed for Windows support, which uses `\` instead of `/` as file separator

Updates https://github.com/VictoriaMetrics/VictoriaMetrics/issues/70
2023-03-25 14:33:58 -07:00
Aliaksandr Valialkin
b14d96618c
all: follow-up after 34634ec357
- Use windows.FlushFileBuffers() instead of windows.Fsync() at streamTracker.adviseDontNeed()
  for consistency with implementations for other architectures.
- Use filepath.Base() instead of filepath.Split(), since the dir part isn't used.
  This simplifies the code a bit.

Updates https://github.com/VictoriaMetrics/VictoriaMetrics/issues/70
2023-03-25 11:57:39 -07:00
Nikolay
34634ec357
lib/fs: adds memory map for windows (#3988)
This is a follow-up for 43b24164ef

* lib/fs: adds memory map for windows
it should improve performance for file reading

* lib/storage: replace '/' with os specific separator
it must fix an errors for windows

* lib/fs: mention windows fsync support

* lib/filestream: adds fdatasync for windows writes

Updates https://github.com/VictoriaMetrics/VictoriaMetrics/issues/70
2023-03-25 11:43:19 -07:00
Dmytro Kozlov
5c92022cc6
lib/storage: fix collect downsampling metrics (#489)
* lib/storage: fix downsampling

* lib/storage: update logic

* lib/storage: fix comments, removed unneeded check
2023-03-19 23:34:46 -07:00
Aliaksandr Valialkin
43b24164ef
all: add Windows build for VictoriaMetrics
This commit changes background merge algorithm, so it becomes compatible with Windows file semantics.

The previous algorithm for background merge:

1. Merge source parts into a destination part inside tmp directory.
2. Create a file in txn directory with instructions on how to atomically
   swap source parts with the destination part.
3. Perform instructions from the file.
4. Delete the file with instructions.

This algorithm guarantees that either source parts or destination part
is visible in the partition after unclean shutdown at any step above,
since the remaining files with instructions is replayed on the next restart,
after that the remaining contents of the tmp directory is deleted.

Unfortunately this algorithm doesn't work under Windows because
it disallows removing and moving files, which are in use.

So the new algorithm for background merge has been implemented:

1. Merge source parts into a destination part inside the partition directory itself.
   E.g. now the partition directory may contain both complete and incomplete parts.
2. Atomically update the parts.json file with the new list of parts after the merge,
   e.g. remove the source parts from the list and add the destination part to the list
   before storing it to parts.json file.
3. Remove the source parts from disk when they are no longer used.

This algorithm guarantees that either source parts or destination part
is visible in the partition after unclean shutdown at any step above,
since incomplete partitions from step 1 or old source parts from step 3 are removed
on the next startup by inspecting parts.json file.

This algorithm should work under Windows, since it doesn't remove or move files in use.
This algorithm has also the following benefits:

- It should work better for NFS.
- It fits object storage semantics.

The new algorithm changes data storage format, so it is impossible to downgrade
to the previous versions of VictoriaMetrics after upgrading to this algorithm.

Updates https://github.com/VictoriaMetrics/VictoriaMetrics/issues/3236
Updates https://github.com/VictoriaMetrics/VictoriaMetrics/issues/3821
Updates https://github.com/VictoriaMetrics/VictoriaMetrics/issues/70
2023-03-19 01:36:51 -07:00
Aliaksandr Valialkin
6460475e3b
lib/{mergeset,storage}: prevent from long wait time when creating a snapshot under high data ingestion rate
Updates https://github.com/VictoriaMetrics/VictoriaMetrics/issues/3551
Updates https://github.com/VictoriaMetrics/VictoriaMetrics/pull/3873
2023-03-19 00:15:30 -07:00
Aliaksandr Valialkin
a26c6628fd
lib/{fs,mergeset,storage}: substitute os.Open()+os.File.Readdir() with os.ReadDir()
This simplifies code a bit
2023-03-17 21:03:37 -07:00
Zakhar Bessarab
6a5d236245
lib/storage: log original labels set when label value is truncated (#3952)
lib/storage: log original labels set when label value is truncated
2023-03-14 10:59:40 +01:00
Nikolay
927d9da270
lib/storage: correctly handle io.EOF error for pre-fetched metrics (#3946)
io.EOF shouldn't be returned from this function. It breaks all search
API logic and may result in empty query results.
2023-03-11 23:29:43 -08:00
Nikolay
6bfe9cc733
lib{mergset,storage}: prevent possible race condition with logging st… (#3900)
lib{mergset,storage}: prevent possible race condition with logging stats for merges

Previously partwrapper could be release by background process and reference for part may be invalid 
during logging stats. It will lead to panic at vmstorage
https://github.com/VictoriaMetrics/VictoriaMetrics/issues/3897
2023-03-03 12:33:42 +01:00
Aliaksandr Valialkin
0d3f31f60e
lib/storage: follow-up for 39cdc546dd
- Use flag.Duration instead of flagutil.Duration for -snapshotCreateTimeout,
  since the flagutil.Duration is intended mostly for big durations, e.g. days, months and years,
  while the -snapshotCreateTimeout is usually smaller than one hour.
- Add links to https://docs.victoriametrics.com/#how-to-work-with-snapshots in docs/CHANGELOG.md,
  so readers could easily find the corresponding docs when reading the changelog.
- Properly remove all the created directories on unsuccessful attempt to create
  snapshot in Storage.CreateSnapshot().

Updates https://github.com/VictoriaMetrics/VictoriaMetrics/issues/3551
2023-02-27 13:07:38 -08:00
Zakhar Bessarab
39cdc546dd
lib/storage: enhancements for snapshots process (#3873)
* lib/{fs,mergeset,storage}: skip `.must-remove.` dirs when creating snapshot (#3858)

* lib/{mergeset,storage}: add timeout configuration for snapshots creation, remove incomplete snapshots from storage

* docs: fix formatting

* app/vmstorage: add metrics to track status of snapshots

* app/vmstorage: use `vm_http_requests_total` metric for snapshot endpoints metrics, rename new flag to make name more clear

Signed-off-by: Zakhar Bessarab <z.bessarab@victoriametrics.com>

* app/vmstorage: update flag name in docs

Signed-off-by: Zakhar Bessarab <z.bessarab@victoriametrics.com>

* app/vmstorage: reflect new metrics names change in docs

Signed-off-by: Zakhar Bessarab <z.bessarab@victoriametrics.com>

---------

Signed-off-by: Zakhar Bessarab <z.bessarab@victoriametrics.com>
Co-authored-by: Aliaksandr Valialkin <valyala@victoriametrics.com>
2023-02-27 12:12:03 -08:00
Zakhar Bessarab
d8eaa511b0
lib/{fs,mergeset,storage}: skip .must-remove. dirs when creating snapshot (#3858) (#3867) 2023-02-24 12:38:42 -08:00
Oleksandr Redko
9fff48c3e3
app,lib: fix typos in comments (#3804) 2023-02-13 13:27:13 +01:00
Aliaksandr Valialkin
3ec8a4dc80
lib/{mergeset,storage}: allow at least 3 concurrent flushes during background merges on systems with 1 or 2 CPU cores
This should prevent from data ingestion slowdown and query performance degradation
on systems with small number of CPU cores (1 or 2), when big merge is performed.

This should help https://github.com/VictoriaMetrics/VictoriaMetrics/issues/3790

Updates https://github.com/VictoriaMetrics/VictoriaMetrics/issues/3337
2023-02-11 12:08:52 -08:00
Nikolay
9254e494f9
lib/storage: fixes finalDedup for backfilled data (#3737)
previously historical data backfilling may trigger force merge for previous month every hour
it consumes cpu, disk io and decrease cluster performance.
Following commit fixes it by applying deduplication for InMemoryParts
2023-02-01 09:54:21 -08:00
Nikolay
465a285324
lib/storage: properly release parts inMerge lock (#3711)
if storage doesn't have enough disk space, finalDedupWatcher holds inMerge lock for all parts and never release it until storage restart
2023-01-26 08:05:20 -08:00
Aliaksandr Valialkin
ba5a6c851c
lib/storage: use deterministic random generator in tests
Updates https://github.com/VictoriaMetrics/VictoriaMetrics/issues/3683
2023-01-23 20:10:32 -08:00
Aliaksandr Valialkin
2ac530eb28
lib/{storage,mergeset}: wake up background merges as soon as there is a potential work for them
Updates https://github.com/VictoriaMetrics/VictoriaMetrics/issues/3647
2023-01-18 01:10:18 -08:00
Aliaksandr Valialkin
b8409d6600
lib/{storage,mergeset}: do not run assisted merges when flushing pending samples to parts
Assisted merges are intended to be performed by goroutines, which accept the incoming samples,
in order to limit the data ingestion rate.

The worker, which converts pending samples to parts, shouldn't be penalized by assisted merges,
since this may result in increased number of pending rows as seen at https://github.com/VictoriaMetrics/VictoriaMetrics/issues/3647#issuecomment-1385039142
when the assisted merge takes too much time.
2023-01-18 00:20:58 -08:00
Aliaksandr Valialkin
1ac025bbc9
lib/storage: use better naming for a function returning new []rawRows - newRawRowsBlock() -> newRawRows() 2023-01-18 00:01:03 -08:00
Aliaksandr Valialkin
09d7fa2737
lib/{mergeset,storage}: do not slow down concurrently executed queries during assisted merges
Updates https://github.com/VictoriaMetrics/VictoriaMetrics/issues/3647
Updates https://github.com/VictoriaMetrics/VictoriaMetrics/issues/3641
Updates https://github.com/VictoriaMetrics/VictoriaMetrics/issues/648
Updates https://github.com/VictoriaMetrics/VictoriaMetrics/issues/291
2023-01-16 14:31:52 -08:00
Aliaksandr Valialkin
2f3ddd4884
app/vmselect/promql: avoid memory allocations and copying from source timeseries to the returned result at timeseriesToResult() 2023-01-09 22:38:59 -08:00
Aliaksandr Valialkin
7afcca0c51
all: use metricsql.CompileRegexp instead of regexp.Compile for compiling regexps used in graphite queries
This should speed up repeated queries, since metricsql.CompileRegexp returns regexps from the cache
on subsequent calls for the same input regexp.
2023-01-09 21:43:08 -08:00
Aliaksandr Valialkin
41e00a0df7
lib/storage: simplify the fix from 488940502c
Updates https://github.com/VictoriaMetrics/VictoriaMetrics/issues/3566
2023-01-07 01:04:43 -08:00
Dmytro Kozlov
488940502c
lib/storage: fix returning camelcase label names (#3608)
* lib/storage: fix returning camelcase label names

* doc: add change log

* Update docs/CHANGELOG.md

* Update docs/CHANGELOG.md

Co-authored-by: Aliaksandr Valialkin <valyala@victoriametrics.com>
2023-01-07 00:50:14 -08:00
Aliaksandr Valialkin
c63755c316
lib/writeconcurrencylimiter: improve the logic behind -maxConcurrentInserts limit
Previously the -maxConcurrentInserts was limiting the number of established client connections,
which write data to VictoriaMetrics. Some of these connections could be idle.
Such connections do not consume big amounts of CPU and RAM, so there is a little sense in limiting
the number of such connections. So now the -maxConcurrentInserts command-line option
limits the number of concurrently executed insert requests, not including idle connections.

It is recommended removing -maxConcurrentInserts command-line option, since the default value
for this option should work good for most cases.
2023-01-06 22:20:19 -08:00
Roman Khavronenko
5bdd880142
vmstorage: add more context to the flock acquiring msg (#3584)
See https://github.com/VictoriaMetrics/VictoriaMetrics/issues/3578

Signed-off-by: hagen1778 <roman@victoriametrics.com>

Signed-off-by: hagen1778 <roman@victoriametrics.com>
2023-01-05 18:30:42 -08:00
Aliaksandr Valialkin
1b16118e17
lib/{storage,mergeset}: tune the threshold for assisted merge
The https://github.com/VictoriaMetrics/VictoriaMetrics/issues/3425#issuecomment-1359117221
reveals that CPU usage for incoming queries may significantly increase when the number
of in-memory parts becomes too big.

This commit reduces the maximum number of in-memory parts before starting the assisted merge
during data ingestion. This should reduce CPU usage for incoming queries,
since they need to inspect lower number of in-memory parts.

This should help https://github.com/VictoriaMetrics/VictoriaMetrics/issues/3425
2022-12-28 14:39:24 -08:00
Aliaksandr Valialkin
4e55b67a44
lib/storage: clear the err if it is set to io.EOF when searching for the TSID by metricID
This is expected error after when recently added indexdb data isn't available for search yet
or wasn't flushed to disk after unclean shutdown of VictoriaMetrics.

Updates https://github.com/VictoriaMetrics/VictoriaMetrics/issues/3515
2022-12-20 14:05:29 -08:00
Aliaksandr Valialkin
944effca54
lib/storage: do not check for the result returned by db.doExtDB() where this isn't necessary
This simplifies the code a bit
2022-12-19 13:23:13 -08:00
Aliaksandr Valialkin
6c98b56935
lib/storage: search for TSIDs for the given metricIDs in the previous indexdb if they aren't found in the current indexdb
The issue triggers after the indexdb rotation for time series, which stop receiving new samples.
This results in missing data for such time series in query responses.

This commit should address the https://github.com/VictoriaMetrics/VictoriaMetrics/issues/3502

The issue has been introduced in 2dd93449d8
2022-12-19 12:03:09 -08:00
Aliaksandr Valialkin
dc0b08efb0
lib/storage: optimize partSearch.searchBHS() for common case when the TSID for the current block header is bigger or equal to the current tsid
This should help improving performance at https://github.com/VictoriaMetrics/VictoriaMetrics/issues/3425
2022-12-19 10:28:03 -08:00
Aliaksandr Valialkin
057fb2120b
lib/storage: properly set buf capacity inside marshalMetricID
Previously it was always set to 0. In theory this could result into incorrect marshaling
of metricIDs.

The issue has been introduced in 5e4dfe50c6
2022-12-19 10:14:38 -08:00
Aliaksandr Valialkin
ad8852759d
lib/storage: skip missing tsids in the current block header by using binary search
This improves performance by up to 10x when big number of the requested TSIDs
are missing in the searched parts.

This should help https://github.com/VictoriaMetrics/VictoriaMetrics/issues/3425
2022-12-14 22:06:51 -08:00
Aliaksandr Valialkin
4de9d35458
lib/flagutil/bytes.go: properly handle values bigger than 2GiB on 32-bit architectures
This fixes handling of values bigger than 2GiB for the following command-line flags:

- -storage.minFreeDiskSpaceBytes
- -remoteWrite.maxDiskUsagePerURL
2022-12-14 19:26:31 -08:00
Aliaksandr Valialkin
0d41d933e9
lib/mergeset: reduce the parts threshold before starting assisted merges
This should improve query speed in general case.

This is a follow-up for d1af6046c7
2022-12-13 09:13:49 -08:00
Aliaksandr Valialkin
d1af6046c7
lib/{mergeset,storage}: do not block small merges by pending big merges - assist with small merges instead
Blocked small merges may result into big number of small parts, which, in turn,
may result in increased CPU and memory usage during queries, since queries need to inspect
all the existing small parts.

The issue has been introduced in 8189770c50

Updates https://github.com/VictoriaMetrics/VictoriaMetrics/issues/3337
2022-12-12 17:00:50 -08:00
Aliaksandr Valialkin
5b9e6b9d24
lib/storage: follow-up after 7c0ae3a86a
- Update docs at https://docs.victoriametrics.com/#deduplication
- Optimize the deduplication loop a bit

Updates https://github.com/VictoriaMetrics/VictoriaMetrics/issues/3333
2022-12-08 18:16:57 -08:00
Roman Khavronenko
7c0ae3a86a
lib/storage: keep sample with the biggest value on timestamp conflict (#3421)
The change leaves raw sample with the biggest value for identical
timestamps per each `-dedup.minScrapeInterval` discrete interval
when the deduplication is enabled.

```
benchstat old.txt new.txt
name                                         old time/op    new time/op    delta
DeduplicateSamples/minScrapeInterval=1s-10      817ns ± 2%     832ns ± 3%      ~     (p=0.052 n=10+10)
DeduplicateSamples/minScrapeInterval=2s-10     1.56µs ± 1%    2.12µs ± 0%   +35.19%  (p=0.000 n=9+7)
DeduplicateSamples/minScrapeInterval=5s-10     1.32µs ± 3%    1.65µs ± 2%   +25.57%  (p=0.000 n=10+10)
DeduplicateSamples/minScrapeInterval=10s-10    1.13µs ± 2%    1.50µs ± 1%   +32.85%  (p=0.000 n=10+10)

name                                         old speed      new speed      delta
DeduplicateSamples/minScrapeInterval=1s-10   10.0GB/s ± 2%   9.9GB/s ± 3%      ~     (p=0.052 n=10+10)
DeduplicateSamples/minScrapeInterval=2s-10   5.24GB/s ± 1%  3.87GB/s ± 0%   -26.03%  (p=0.000 n=9+7)
DeduplicateSamples/minScrapeInterval=5s-10   6.22GB/s ± 3%  4.96GB/s ± 2%   -20.37%  (p=0.000 n=10+10)
DeduplicateSamples/minScrapeInterval=10s-10  7.28GB/s ± 2%  5.48GB/s ± 1%   -24.74%  (p=0.000 n=10+10)
```

https://github.com/VictoriaMetrics/VictoriaMetrics/issues/3333
Signed-off-by: hagen1778 <roman@victoriametrics.com>

Signed-off-by: hagen1778 <roman@victoriametrics.com>
2022-12-08 18:06:11 -08:00
Aliaksandr Valialkin
d99d222f0a
lib/{storage,mergeset}: log the duration for flushing in-memory parts on graceful shutdown 2022-12-05 21:30:48 -08:00
Aliaksandr Valialkin
8189770c50
all: add -inmemoryDataFlushInterval command-line flag for controlling the frequency of saving in-memory data to disk
The main purpose of this command-line flag is to increase the lifetime of low-end flash storage
with the limited number of write operations it can perform. Such flash storage is usually
installed on Raspberry PI or similar appliances.

For example, `-inmemoryDataFlushInterval=1h` reduces the frequency of disk write operations
to up to once per hour if the ingested one-hour worth of data fits the limit for in-memory data.

The in-memory data is searchable in the same way as the data stored on disk.
VictoriaMetrics automatically flushes the in-memory data to disk on graceful shutdown via SIGINT signal.
The in-memory data is lost on unclean shutdown (hardware power loss, OOM crash, SIGKILL).

Updates https://github.com/VictoriaMetrics/VictoriaMetrics/issues/3337
2022-12-05 15:16:14 -08:00
Aliaksandr Valialkin
544ea89f91
lib/{mergeset,storage}: add start background workers via startBackgroundWorkers() function 2022-12-04 00:01:04 -08:00
Aliaksandr Valialkin
33dda2809b
lib/mergeset: panic when too long item is passed to Table.AddItems() 2022-12-03 23:32:16 -08:00
Aliaksandr Valialkin
932c1f90ae
lib/storage: remove duplicate logging for filepath on errors 2022-12-03 23:15:22 -08:00
Aliaksandr Valialkin
044a304adb
lib/storage: pass a single arg - rowsPerBlock - to getCompressLevel() function instead of two args 2022-12-03 23:10:16 -08:00
Aliaksandr Valialkin
cb44976716
lib/{storage,mergeset}: use a single sync.WaitGroup for all background workers
This simplifies the code
2022-12-03 23:03:08 -08:00
Aliaksandr Valialkin
28e6d9e1ff
lib/storage: properly pass retentionMsecs to OpenStorage() at TestIndexDBRepopulateAfterRotation 2022-12-03 23:02:10 -08:00
Aliaksandr Valialkin
343c69fc15
lib/{mergeset,storage}: pass compressLevel to blockStreamWriter.InitFromInmemoryPart
This allows packing in-memory blocks with different compression levels
depending on its contents. This may save memory usage.
2022-12-03 22:46:48 -08:00
Aliaksandr Valialkin
f3e3a3daeb
lib/{mergeset,storage}: take into account byte slice capacity when returning the size of in-memory part
This results in more correct reporting of memory usage for in-memory parts
2022-12-03 22:30:36 -08:00
Aliaksandr Valialkin
45299efe22
lib/{storage,mergeset}: consistency rename: `flushRaw{Rows,Items} -> flushPending{Rows,Items} 2022-12-03 22:17:46 -08:00
Aliaksandr Valialkin
5ca58cc4fb
lib/storage: optimization: do not scan block for rows outside retention if it is covered by the retention 2022-12-03 22:14:12 -08:00
Aliaksandr Valialkin
152ac564ab
lib/storage: remove logging redundant path values in a single error message 2022-12-03 22:13:13 -08:00
Aliaksandr Valialkin
05c65bd83f
lib/storage: speed up search for data block for the given tsids
Use binary search instead of linear scan for looking up the needed
data block inside index block.

Updates https://github.com/VictoriaMetrics/VictoriaMetrics/issues/3425
2022-12-03 20:58:32 -08:00
Aliaksandr Valialkin
299285b147
lib/storage: fix TestUpdateCurrHourMetricIDs test when it runs on the first hour of the day by UTC 2022-12-02 18:52:37 -08:00
Aliaksandr Valialkin
e9636b4c69
lib/{mergeset,storage}: re-use the code for removing isInMerge flag at parts
Move the common code into releasePartsToMerge() method and consistently use it throughout the code.
2022-12-02 18:52:37 -08:00
匠心零度
fa0ce10275
lib/storage: remove extra error check (#3396) 2022-11-28 16:43:31 -08:00
Aliaksandr Valialkin
daa70e6560
lib/storage: follow-up for 790768f20b
- Document the bugfix at docs/CHANGELOG.md
- Simplify the bugfix a bit
2022-11-07 14:04:08 +02:00
Aliaksandr Valialkin
f9dc3da9e2
lib/storage: typo fix after 32d48f8dfbb03174858c00bdfe6d9d22431dc8d8 2022-11-07 13:58:27 +02:00
Aliaksandr Valialkin
dd88c628aa
lib/storage: remove unused isFull field from hourMetricIDs struct 2022-11-07 13:58:26 +02:00
Łukasz Marszał
790768f20b
Fix issue-3309 - currHourMetricIDs shouldn't contain metrics from prev hour (#3320)
* fix issue-3309 currHourMetricIDs shouldn't contain metrics from prev hour

* Update storage.go
2022-11-07 13:55:37 +02:00
Aliaksandr Valialkin
c4265322f4
lib/fs: add canOverwrite arg to WriteFileAtomically when it is allowed to overwrite the file atomically if it already exists 2022-10-26 01:07:34 +03:00
Aliaksandr Valialkin
8e998aa1a1
lib/storage: add support for retention filters (aka multiple retentions for distinct sets of time series)
Updates https://github.com/VictoriaMetrics/VictoriaMetrics/issues/143
Updates https://github.com/VictoriaMetrics/VictoriaMetrics/issues/289
2022-10-24 16:40:20 +03:00
Aliaksandr Valialkin
dba218a8ce
lib/storage: skip blocks outside the configured retention during search
Blocks outside the configured retention are eventually deleted during background merge.
But such blocks may reside in the storage for long time until background merge.
Previously VictoriaMetrics could spend additional CPU time on processing such blocks
during search queries. Now these blocks are skipped.
2022-10-24 02:52:44 +03:00
Aliaksandr Valialkin
e2f0b76ebf
lib/storage: do not pass retentionMsecs and isReadOnly args explicitly - access them via Storage arg
This makes code easier to read.

This is a follow-up after d2d30581a0
2022-10-24 01:31:04 +03:00
Aliaksandr Valialkin
89a1108b1a
lib/storage: small code cleanups 2022-10-24 01:17:47 +03:00
Aliaksandr Valialkin
05512fdd74
lib/storage: re-use newTestStorage() instead of manually initializing Storage mock
This is a follow-up for d2d30581a0
2022-10-23 16:24:00 +03:00
Aliaksandr Valialkin
d2d30581a0
lib/storage: pass Storage to table and partition instead of getDeletedMetricIDs callback
This improves code readability a bit.
2022-10-23 16:10:04 +03:00
Aliaksandr Valialkin
54f35c175c
lib/storage: small refactoring: move retentionDeadline to blockStreamMerger
This allows defining per-block retention in the future by updating the getRetentionDeadline function
2022-10-23 16:10:02 +03:00
Aliaksandr Valialkin
187e294a53
lib/storage: use a single reference to the currently merged block - bsm.Block during the block merge loop 2022-10-23 14:08:57 +03:00
Aliaksandr Valialkin
d0a9ca1bc2
lib/storage: properly pass uint64 constant to fmt.Errorf on 32-bit platforms 2022-10-23 12:48:00 +03:00
Aliaksandr Valialkin
5e4dfe50c6
lib/storage: subsitute searchTSIDs functions with more lightweight searchMetricIDs function
The searchTSIDs function was searching for metricIDs matching the the given tag filters
and then was locating the corresponding TSID entries for the found metricIDs.

The TSID entries aren't needed when searching for time series names (aka MetricName),
so this commit removes the uneeded TSID search from the implementation of /api/v1/series API.
This improves perfromance of /api/v1/series calls.

This commit also improves performance a bit for /api/v1/query and /api/v1/query_range calls,
since now these calls cache small metricIDs instead of big TSID entries
in the indexdb/tagFilters cache (now this cache is named indexdb/tagFiltersToMetricIDs)
without the need to compress the saved entries in order to save cache space.

This commit also removes concurrency limiter during searching for matching time series,
which was introduced in 8f16388428, since the concurrency
for all the read queries is already limited with -search.maxConcurrentRequests command-line flag.

Updates https://github.com/VictoriaMetrics/VictoriaMetrics/issues/648
2022-10-23 12:23:47 +03:00
Aliaksandr Valialkin
4128ad71e2
lib/storage: move common code to newRawRowsBlock() function 2022-10-21 14:46:55 +03:00
Aliaksandr Valialkin
b5674164c6
lib/storage: simplify code a bit after 3f5959c053 2022-10-21 14:39:27 +03:00
Aliaksandr Valialkin
fd7c86ae25
lib/{mergeset,storage}: simplify the code a bit after ae55ad8749 2022-10-21 14:33:03 +03:00
Aliaksandr Valialkin
99d67ac8ad
lib/storage: validate timestamps in the block only if they use encoding, which needs validation
This reduces CPU usage when there is no sense in validating timestamps.

This is a follow-up for 5fa9525498

Updates https://github.com/VictoriaMetrics/VictoriaMetrics/issues/2998
Updates https://github.com/VictoriaMetrics/VictoriaMetrics/issues/3011
2022-10-21 00:52:32 +03:00
Aliaksandr Valialkin
3f5959c053
lib/storage: try generating initial parts from inmemory rows with identical sizes under high ingestion rate
This should improve background merge rate under high load a bit
2022-10-20 23:28:24 +03:00
Aliaksandr Valialkin
150e99d403
lib/{mergeset,storage}: avoid unaligned 64-bit atomic operation panic on 32-bit platforms
The panic has been introduced in 68f3a02589

While at it, add padding to shard structs in order to avoid false sharing on mordern CPUs

This should improve scalability on systems with many CPU cores
2022-10-20 16:25:43 +03:00
Aliaksandr Valialkin
fb50730ba7
lib/storage: double the number of rawRows shards on multi-core systems
This should increase data ingestion scalability on multi-core systems at the cost of slightly higher memory usage
2022-10-17 18:19:51 +03:00
Aliaksandr Valialkin
ae55ad8749
lib/{storage,mergeset}: do not hold per-shard lock in fast path when adding per-shard items to the flush list 2022-10-17 18:01:26 +03:00
Aliaksandr Valialkin
db16759c68
lib/storage: optimize matching speed for non-trivial regexp filters
Wrap re.Match into bytesutil.FastStringMatcher.

This increases performance for `{foo=~"complex_regex_here"}` filters
by up to 4x.
2022-10-01 12:06:06 +03:00
Aliaksandr Valialkin
042a532f70
lib/storage: substitute remaining calls to fs.MustRemoveAll with fs.MustRemoveDirAtomic
Updates https://github.com/VictoriaMetrics/VictoriaMetrics/issues/3038
2022-09-13 16:17:38 +03:00
Aliaksandr Valialkin
68e32b0764
lib/storage: atomically remove parts inside partitions
Updates https://github.com/VictoriaMetrics/VictoriaMetrics/issues/3038
2022-09-13 16:17:38 +03:00
Aliaksandr Valialkin
340ada871d
lib/storage: atomically remove partitions, which went outside the configured retention
Updates https://github.com/VictoriaMetrics/VictoriaMetrics/issues/3038
2022-09-13 16:17:37 +03:00
Aliaksandr Valialkin
978dcb4574
lib/storage: properly remove cache directory contents if reset_cache_on_startup file is located there
Previously the cache directory was removed. This could result in error when the cache directory
is mounted to a separate filesystem.
2022-09-13 16:17:36 +03:00
Aliaksandr Valialkin
5f28ca1f42
lib/storage: atomically remove snapshot directories
Updates https://github.com/VictoriaMetrics/VictoriaMetrics/issues/3038
2022-09-13 16:17:36 +03:00
Aliaksandr Valialkin
5fa9525498
lib/storage: verify that timestamps in block are in the range specified by blockHeader.{Min,Max}Timestamp when upacking the block
This should reduce chances of unnoticed on-disk data corruption.

Updates https://github.com/VictoriaMetrics/VictoriaMetrics/issues/2998
Updates https://github.com/VictoriaMetrics/VictoriaMetrics/issues/3011

This change modifies the format for data exported via /api/v1/export/native -
now this data contains MaxTimestamp and PrecisionBits fields from blockHeader.

This is OK, since the native export format is undocumented.
2022-09-06 13:08:09 +03:00
Aliaksandr Valialkin
0ad3bbadd3
lib/regexutil: add Simplify() function for simplifying the regular expression 2022-08-26 11:57:12 +03:00
Aliaksandr Valialkin
0d4ea03a73
lib/promrelabel: optimize action: {labeldrop,labelkeep,keep,drop} with regex containing alternate values
For example, the following relabeling rule must work much faster now:

- action: labeldrop
  regex: "foo|bar|baz"
2022-08-24 17:54:29 +03:00
Aliaksandr Valialkin
0d46e24af5
lib/storage: increase the maximum possible or values extracted from regexp from 20 to 100
This should improve time series search speed for regexp filters with big number of `or` values.
2022-08-24 17:15:25 +03:00
Aliaksandr Valialkin
fdbf5b5795
lib/storage: ignore start text and end text anchors in getOrValues(regexp) function
This is OK, since the anchors are implicitly applied to the whole regexp.
This optimization should improve the speed for regexp series filters with explicit $ and ^ anchors.
For example, `{label="^(foo|bar)$"}`
2022-08-24 17:12:52 +03:00
Aliaksandr Valialkin
796aa310c2
app/vmstorage: expose vm_{hourly,daily}_series_limit_{max,current}_series metrics if -storage.max{Hourly,Daily}Series limits are set
These metrics allow alerting when the number of unique series approach the limit.
For example, the following query alerts when the number of series reaches 90% of the configured limit:

    vm_hourly_series_limit_current_series / vm_hourly_series_limit_max_series > 0.9
2022-08-24 13:44:04 +03:00
Aliaksandr Valialkin
1f89278d88
all: subsitute ioutil.ReadAll with io.ReadAll
ioutil.ReadAll is deprecated since Go1.16 - see https://tip.golang.org/doc/go1.16#ioutil
VictoriaMetrics requires at least Go1.18, so it is OK to switch from ioutil.ReadAll to io.ReadAll.

This is a follow-up for 02ca2342ab
2022-08-22 00:16:37 +03:00
Aliaksandr Valialkin
9f94c295ab
all: use os.{Read|Write}File instead of ioutil.{Read|Write}File
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
2022-08-21 23:52:35 +03:00
Roman Khavronenko
d59d829cdb
lib/storage: bump max merge concurrency for small parts to 15 (#2997)
* lib/storage: bump max merge concurrency for small parts to 15

The change is based on the feedback from users on github.
Thier examples show, that limit of 8 sometimes become a
bottleneck. Users report that without limit concurrency
can climb up to 15-20 merges at once.

Signed-off-by: hagen1778 <roman@victoriametrics.com>

* Update lib/storage/partition.go

Signed-off-by: hagen1778 <roman@victoriametrics.com>
Co-authored-by: Aliaksandr Valialkin <valyala@victoriametrics.com>
2022-08-21 23:32:08 +03:00
Roman Khavronenko
31f922944e
lib/storage: fix the search for empty label name (#2991)
* lib/storage: fix the search for empty label name

Signed-off-by: hagen1778 <roman@victoriametrics.com>

* Apply suggestions from code review

Signed-off-by: hagen1778 <roman@victoriametrics.com>
Co-authored-by: Aliaksandr Valialkin <valyala@victoriametrics.com>
2022-08-17 21:32:25 +03:00
Aliaksandr Valialkin
b0e1bb517e
lib/storage: typo fix in comments after f830edc0bc 2022-08-16 13:44:45 +03:00
Aliaksandr Valialkin
f830edc0bc
lib/storage: improve performance for /api/v1/labels and /api/v1/label/.../values endpoints when match[] filter matches small number of time series
Updates https://github.com/VictoriaMetrics/VictoriaMetrics/issues/2978
2022-08-16 13:32:40 +03:00
Roman Khavronenko
a0e7432e42
lib/storage: prevent excessive loops when storage is in RO (#2962)
* lib/storage: prevent excessive loops when storage is in RO

Returning nil error when storage is in RO mode results
into excessive loops and function calls which could
result into CPU exhaustion. Returning an err instead
will trigger delays in the for loop and save some resources.

Signed-off-by: hagen1778 <roman@victoriametrics.com>

* document the change

Co-authored-by: Aliaksandr Valialkin <valyala@victoriametrics.com>
2022-08-09 12:17:00 +03:00
Aliaksandr Valialkin
5a4c58f9a2
lib/storage: explain why the GetOrCreateTSIDByName function doesnt check whether the per-day entry for the given date exists if TSID is found in global index 2022-08-02 09:12:29 +03:00
Aliaksandr Valialkin
78520f2702
lib/storage: do not compress small number of tsids when storing them in tagFiltersCache
This speeds up tsids retreival from the cache for 0-2 tsids
2022-07-30 00:08:51 +03:00
guidao
91faa152a5
add next retention metric (#2863)
Co-authored-by: wangfeng <wangfeng@zhihu.com>
2022-07-13 12:37:04 +03:00
Aliaksandr Valialkin
5c8eee26bf
all: make fmt via the upcoming Go1.19 2022-07-11 19:22:15 +03:00
Aliaksandr Valialkin
77cbbacfdb
lib/vmselectapi: pass storage.SearchQuery to API calls instead of []*storage.TagFilters + storage.TimeRange + maxMetrics
This reduces the number of args to vmselectapi calls
2022-07-06 12:37:54 +03:00
Aliaksandr Valialkin
e1b8059086
lib/vmselectapi: rename deleteMetrics to more correct deleteSeries 2022-07-06 12:37:54 +03:00
Aliaksandr Valialkin
a60e03b3a7
lib/vmselectapi: use string type for tagKey and tagValuePrefix args at TagValueSuffixes()
This improves the API consistency
2022-07-06 12:37:53 +03:00
Aliaksandr Valialkin
edc76286ac
lib/storage: put the (date, metricID) entry in dateMetricIDCache just after the corresponding series is registered in the per-day inverted index
Previously the time series could be put into dateMetricIDCache without
registering in the per-day inverted index if GetOrCreateTSIDByName
finds TSID entry in the global index. This could lead to missing
series in query results.

The issue has been introduced in the commit 55e7afae3a,
which has been included in VictoriaMetrics v1.78.0
2022-07-05 14:54:03 +03:00
Aliaksandr Valialkin
3e2dd85f7d
all: readability improvements for query traces
- show dates in human-readable format, e.g. 2022-05-07, instead of a numeric value
- limit the maximum length of queries and filters shown in trace messages
2022-06-30 18:20:33 +03:00
Aliaksandr Valialkin
a350d1e81c
lib/storage: return marshaled metric names from SearchMetricNames
Previously SearchMetricNames was returning unmarshaled metric names.
This wasn't great for vmstorage, which should spend additional CPU time
for marshaling the metric names before sending them to vmselect.

While at it, remove possible duplicate metric names, which could occur when
multiple samples for new time series are ingested via concurrent requests.

Also sort the metric names before returning them to the client.
This simplifies debugging of the returned metric names across repeated requests to /api/v1/series
2022-06-28 18:17:15 +03:00
Aliaksandr Valialkin
2c836bd398
lib/storage: put into query trace the number of found entries in SearchMetricNames 2022-06-28 14:50:53 +03:00
Aliaksandr Valialkin
e578549b8a
app/vmselect: optimize /api/v1/series a bit for time ranges smaller than one day 2022-06-28 13:02:47 +03:00
Aliaksandr Valialkin
a963b2a0aa
all: show timeRange in traces in human-readable format instead of timestamps in milliseconds 2022-06-27 13:45:51 +03:00
Aliaksandr Valialkin
ba514284f1
lib/storage: add querytracer to more contexts
querytracer has been added to the following storage.Storage methods:
- RegisterMetricNames
- DeleteMetrics
- SearchTagValueSuffixes
- SearchGraphitePaths
2022-06-27 13:45:51 +03:00
Aliaksandr Valialkin
134751e43e
all: locate throttled loggers via logger.WithThrottler() only once and then use them
This reduces the contention on logThrottlerRegistryMu mutex when logger.WithThrottler()
is called frequently from concurrent goroutines.
2022-06-27 13:45:50 +03:00
Aliaksandr Valialkin
b958fc7846
lib/storage: properly take into account already registered series when -storage.maxHourlySeries or -storage.maxDailySeries limits are enabled
The commit 5fb45173ae takes into account only newly registered series
when applying cardinality limits. This means that the cardinality limit could be exceeded with already registered series.
This commit returns back accounting for already registered series when applying cardinality limits.
2022-06-20 13:47:47 +03:00
Aliaksandr Valialkin
55e7afae3a
lib/storage: create per-day indexes together with global indexes when registering new time series
Previously the creation of per-day indexes and global indexes
for the newly registered time series was decoupled.

Now global indexes and per-day indexes for the current day are created toghether for new time series.
This should speed up registering new time series a bit.
2022-06-19 22:42:10 +03:00
Aliaksandr Valialkin
5fb45173ae
lib/storage: do not register new series if -storage.maxHourlySeries or -storage.maxDailySeries limits are exceeded
Previously samples for new series weren't added as expected when series limits were reached,
but new series were still registered in indexdb.
2022-06-19 22:42:09 +03:00
Aliaksandr Valialkin
62e2371a67
lib/storage: reset metric id caches for the previous and the current hour
Updates https://github.com/VictoriaMetrics/VictoriaMetrics/issues/2698
2022-06-19 22:42:09 +03:00
Aliaksandr Valialkin
ec7963208d
app/vmselect: accept focusLabel query arg at /api/v1/status/tsdb
This allows filling the seriesCountByFocusLabelValue list in the /api/v1/status/tsdb response
with label values for the specified focusLabel, which contain the highest number of time series.

TODO: add this to Cardinality explorer at VMUI - https://docs.victoriametrics.com/#cardinality-explorer
2022-06-14 18:36:54 +03:00
Aliaksandr Valialkin
b6c1ca12b7
lib/storage: show top labels with the highest number of series in cardinality explorer 2022-06-14 16:32:38 +03:00
Aliaksandr Valialkin
a75e59700f
lib/storage: improve error message when -search.max* command-line flag values are exceeded 2022-06-14 13:27:59 +03:00
Aliaksandr Valialkin
52cf05c6d2
lib/storage: test GetTSDBStatusWithFiltersForDate on a global time range 2022-06-12 14:27:40 +03:00
Aliaksandr Valialkin
374beb350e
app/vmselect: optimize /api/v1/labels and /api/v1/label/.../values handlers when match[] query arg is passed to them 2022-06-12 04:32:13 +03:00
Aliaksandr Valialkin
2bcb960f17
all: improve query tracing coverage for indexdb search
Updates https://github.com/VictoriaMetrics/VictoriaMetrics/issues/1403
2022-06-09 20:07:07 +03:00
Aliaksandr Valialkin
12ac255dae
lib/querytracer: make it easier to use by passing trace context message to New and NewChild
The context message can be extended by calling Donef.
If there is no need to extend the message, then just call Done.
2022-06-08 21:06:52 +03:00
Dmytro Kozlov
018d2303c4
Cardinality explorer (#2625)
* Cardinality explorer

* vmui, vmselect: updated field name, added description to spinner

* make vmui-update

* updated const name, make vmui-update

* lib/storage: changes calculation for totalSeries values

* added static files

* wip

* wip

* wip

* wip

* docs/CHANGELOG.md: document cardinality explorer feature

See https://github.com/VictoriaMetrics/VictoriaMetrics/issues/2233

Co-authored-by: f41gh7 <nik@victoriametrics.com>
Co-authored-by: Aliaksandr Valialkin <valyala@victoriametrics.com>
2022-06-08 18:43:05 +03:00
Roman Khavronenko
1ee1e986da
lib/storage: limit max mergeConcurrency value for systems with high number of CPUs (#2673)
Workers count for merges affects the max part size during merges. Such behaviour
protects storage from running out of disk space for scenario when all workers
are merging parts with the max size.

This works very well for most cases. But for systems where high number of CPUs
is allocated for vmstorage components this could significantly impact the max
part size and result in more unmerged parts than expected.

While checking multiple production highly loaded setups it was discovered that
`max_over_time(vm_active_merges{type="storage/big}[1h]}"` rarely exceeds 2,
and `max_over_time(vm_active_merges{type="storage/small}[1h]}"` rarely exceeds 4.
The change in this commit limits the max value for concurrency accordingly.

Signed-off-by: hagen1778 <roman@victoriametrics.com>
2022-06-07 14:55:09 +03:00