github-mirrors/VictoriaMetrics
1
0
Fork 0
mirror of https://github.com/VictoriaMetrics/VictoriaMetrics.git synced 2024-11-21 14:44:00 +00:00
Code Issues Projects Releases Packages Wiki Activity
803 commits 150 branches 748 tags 347 MiB
Commit graph

299 commits

Author SHA1 Message Date
Aliaksandr Valialkin
b5645ccbdf app/vmselect/promql: increase the estimated number of time series returned by aggr() by (something) from 100 to 1K, since 100 may result in OOM for high number of time series 2020-01-03 01:02:21 +02:00
Aliaksandr Valialkin
cb3a342882 app/vmselect/promql: add share_le_over_time and share_gt_over_time functions for SLI and SLO calculations 2020-01-03 00:41:16 +02:00
Aliaksandr Valialkin
6f67e0b56b lib/metricsq: add ExpandWithExprs 2019-12-25 22:20:30 +02:00
Aliaksandr Valialkin
1925ee038d Rename lib/promql to lib/metricsql and apply small fixes 2019-12-25 22:03:59 +02:00
Mike Poindexter
bec62e4e43 Split Extended PromQL parsing to a separate library 2019-12-25 22:03:51 +02:00
Aliaksandr Valialkin
d880325cf6 app/vmselect/promql: make sure AdjustStartEnd returns time range covering the same number of points as the initial time range 
This should prevent from the following panic at app/vmselect/promql/binary_op.go:255:

    BUG: len(leftVaues) must match len(rightValues) and len(dstValues)
 2019-12-24 22:45:56 +02:00
Aliaksandr Valialkin
9e19949c6b app/vmselect/promql: adjust calculations for rate and increase for the first value 
These calculations should trigger alerts on `/api/v1/query` for counters starting from values greater than 0.
 2019-12-24 19:39:25 +02:00
Aliaksandr Valialkin
0455c03cb9 app/vmselect/promql: properly calculate rate on the first data point 
It is calculated as `value / scrape_interval`, since the value was missing on the previous scrape,
i.e. we can assume its value was 0 at this time.
 2019-12-24 15:55:52 +02:00
Aliaksandr Valialkin
5cb8d97743 all: use gozstd instead of pure Go zstd for GOARCH=amd64 2019-12-24 12:42:42 +02:00
Aliaksandr Valialkin
5b75984aa9 app/vmselect/netstorage: move MustAdviseSequentialRead to lib/fs 2019-12-23 23:16:11 +02:00
Aliaksandr Valialkin
bea5a8700a app/vmselect: add -search.maxExportDuration command-line flag for limiting /api/v1/export duration 
Updates https://github.com/VictoriaMetrics/VictoriaMetrics/issues/275
 2019-12-20 11:35:22 +02:00
Andrii Dembitskyi
2fba7b6f35 Fix typo in log message 2019-12-19 14:33:20 +02:00
Aliaksandr Valialkin
d03827c57d app/vminsert: return StatusNoContent http response for /api/v1/import to be consistent with other insert handlers 2019-12-19 01:21:54 +02:00
Aliaksandr Valialkin
96ff8d9adb app/vmselect: add ability to pass match[], start and end to /api/v1/labels 
This makes the `/api/v1/labels` handler consistent with already existing functionality for `/api/v1/label/.../values`.

See https://github.com/prometheus/prometheus/issues/6178 for more details.
 2019-12-15 00:20:50 +02:00
Aliaksandr Valialkin
02f6566ce1 app/vmbackup: mention that backups are possible to Ceph and Swift 2019-12-14 01:08:49 +02:00
Aliaksandr Valialkin
bc645152cb app/vminsert: simultaneously accept telnet put and HTTP /api/put OpenTSDB metrics at -opentsdbListenAddr 
Updates https://github.com/VictoriaMetrics/VictoriaMetrics/issues/266
 2019-12-14 00:30:12 +02:00
Aliaksandr Valialkin
cea5a14853 all: rename Extended PromQL to PromQL extensions 2019-12-12 19:25:58 +02:00
Aliaksandr Valialkin
6ddcd162ed all: publish Docker images for the following GOARCH: amd64, arm, arm64, ppc64le and 386 
Updates https://github.com/VictoriaMetrics/VictoriaMetrics/issues/258
 2019-12-11 23:32:59 +02:00
Aliaksandr Valialkin
73b2a3d4b7 app/vmselect/promql: return lower and upper bounds for the estimated percentile from histogram_quantile if third arg is passed 
Updates https://github.com/prometheus/prometheus/issues/5706
 2019-12-11 13:57:26 +02:00
Aliaksandr Valialkin
caa4eb72d9 app/vmselect/promql: return matrix instead of vector on subqueries to /api/v1/query like Prometheus does 2019-12-11 01:00:26 +02:00
Aliaksandr Valialkin
3c076544bf app/vmselect/promql: allow negative offsets 
Updates https://github.com/prometheus/prometheus/issues/6282
 2019-12-11 01:00:23 +02:00
Aliaksandr Valialkin
68e1cf8942 app/vminsert: add /api/v1/import handler 
Updates https://github.com/VictoriaMetrics/VictoriaMetrics/issues/6
 2019-12-09 20:59:04 +02:00
Aliaksandr Valialkin
8501b4a48d app/vminsert: consistency renaming for counters 2019-12-09 16:43:10 +02:00
Aliaksandr Valialkin
293b541784 make vendor-update 2019-12-07 23:10:16 +02:00
Aliaksandr Valialkin
84b57e8974 app/vminsert/influx: add a test case from https://community.librenms.org/t/integration-with-victoriametrics/9689 2019-12-07 23:00:40 +02:00
Aliaksandr Valialkin
c09472dfd9 app/vmselect/promql: add {topk|bottomk}_{min|max|avg|median} aggregate functions for returning the exact k time series on the given time range 
The full list of functions added:
- `topk_min(k, q)` - returns top K time series with the max minimums on the given time range
- `topk_max(k, q)` - returns top K time series with the max maximums on the given time range
- `topk_avg(k, q)` - returns top K time series with the max averages on the given time range
- `topk_median(k, q)` - returns top K time series with the max medians on the given time range
- `bottomk_min(k, q)` - returns bottom K time series with the min minimums on the given time range
- `bottomk_max(k, q)` - returns bottom K time series with the min maximums on the given time range
- `bottomk_avg(k, q)` - returns bottom K time series with the min averages on the given time range
- `bottomk_median(k, q)` - returns bottom K time series with the min medians on the given time range
 2019-12-05 19:26:47 +02:00
Aliaksandr Valialkin
face3d57bf app/vmselect: add placeholders for /api/v1/rules and /api/v1/alerts 2019-12-03 19:36:33 +02:00
Aliaksandr Valialkin
20812008a7 lib/storage: remove metricID with missing metricID->metricName entry 
The metricID->metricName entry can be missing in the indexdb after unclean shutdown
when only a part of entries for new time series is written into indexdb.

Recover from such a situation by removing the broken metricID. New metricID
will be automatically created for time series with the given metricName
when new data point will arive to it.
 2019-12-02 20:46:44 +02:00
Aliaksandr Valialkin
9476b73527 app/vmselect/promql: estimate per-series scrape interval as 0.6 quantile for the first 100 intervals 
This should improve scrape interval estimation for tiem series with gaps.
 2019-12-02 13:42:33 +02:00
Aliaksandr Valialkin
811b7a8303 app/vminsert/influx: allow empty measurement in Influx line protocol 
In this case metric names are mapped directly from field names without any prefixes.
 2019-11-30 23:18:41 +02:00
Aliaksandr Valialkin
75ff524a4e app/vmselect/promql: fix corner case for increase over time series with gaps 
In this case `increase` could return invalid high value for the first point after the gap.
 2019-11-30 01:34:56 +02:00
Aliaksandr Valialkin
96492348cb deployment/docker/certs: update TLS certs source from alpine:3.9 to alpine:3.10 2019-11-29 19:57:29 +02:00
Aliaksandr Valialkin
f733cb2186 lib/backup: cosmetic fixes after #243 2019-11-29 18:07:04 +02:00
glebsam
15b7406f7b Add option to provide custom endpoint for S3, add option to specify S3 config profile (#243) 
* Add option to provide custom endpoint for S3 for use with s3-compatible storages, add option to specify S3 config profile

* make fmt
 2019-11-29 17:59:56 +02:00
Aliaksandr Valialkin
4c859d980c app/vmselect/prometheus: consistently apply nocache arg to /api/v1/query the same way ast to /api/v1/query_range 
Updates https://github.com/VictoriaMetrics/VictoriaMetrics/issues/241
 2019-11-26 22:55:43 +02:00
Aliaksandr Valialkin
110235f789 app/vmselect/prometheus: fix content-type for /api/v1/export responses 
The correct Content-Type should be `application/stream+json` instead of `application/json`
Thanks to Joshua Ryder for pointing to this.
 2019-11-26 17:45:26 +02:00
Aliaksandr Valialkin
205233d9a7 app/vmselect/promql: remove zero timeseries from prometheus_buckets output 2019-11-25 19:10:23 +02:00
Aliaksandr Valialkin
3f99f39e9b app/vmselect/prometheus: reduce default value for -search.latencyOffset from 60s to 30s 
30 seconds should be enough for almost all the cases
 2019-11-25 16:33:42 +02:00
Aliaksandr Valialkin
e91cb34c0e app/vmselect/promql: allow nested parens 2019-11-25 16:13:41 +02:00
Aliaksandr Valialkin
826dfd63a5 vendor: update github.com/VictoriaMetrics/metrics from v1.9.0 to v1.9.1 2019-11-25 15:23:01 +02:00
Aliaksandr Valialkin
0401969d78 app/vmselect/promql: re-use metrics.Histogram when calculating histogram function for each point on the graph 
This should reduce the amounts memory allocations
 2019-11-25 14:24:21 +02:00
Aliaksandr Valialkin
da98703748 app/vmselect/promql: optimize binary search over big number of samples during rollup calculations 2019-11-25 14:01:46 +02:00
Aliaksandr Valialkin
c28876172f app/vmselect/promql: adjust tests after the upgrade of github.com/VictoriaMetrics/metrics from v1.8.3 to v1.9.0 2019-11-25 13:43:57 +02:00
Aliaksandr Valialkin
50ae1879c6 app/vmselect/promql: add histogram aggregate function, which is useful for building heatmaps from multiple time series 2019-11-24 00:04:25 +02:00
Aliaksandr Valialkin
8582b50360 app/vmselect/promql: do not take into account buckets with negative counters in prometheus_buckets 2019-11-23 14:19:25 +02:00
Aliaksandr Valialkin
19dfe52254 app/vmselect/promql: properly handle histogram_quantile(0, ...) with zero buckets 2019-11-23 14:02:35 +02:00
Aliaksandr Valialkin
4bb88843cf app/vmselect: add vm_per_query_{rows,series}_processed_count histograms 2019-11-23 13:23:26 +02:00
Aliaksandr Valialkin
7753c8c0a1 app/vmselect/promql: transparently apply prometheus_buckets in histogram_quantile 2019-11-23 11:48:51 +02:00
Aliaksandr Valialkin
c4287b3c86 app/vmselect/promql: add prometheus_buckets function for converting the upcoming histogram buckets from github.com/VictoriaMetrics/metrics to Prometheus-compatible buckets 2019-11-23 00:20:20 +02:00
Aliaksandr Valialkin
1f3fd2c910 app/vmselect: adjust end arg instead of adjusting start arg if start > end 
`start` arg has higher chances to be set properly comparing to `end` arg,
so it is expected that the `end` arg could be adjusted if it was set incorrectly.
 2019-11-22 16:12:19 +02:00
Aliaksandr Valialkin
7a4635f853 all: remove the remaining mentions of cluster version 2019-11-21 23:18:22 +02:00
Aliaksandr Valialkin
443189fb0a app/{vmbackup,vmrestore}: add -maxBytesPerSecond command-line flag for limiting the used network bandwidth during backup / restore 2019-11-19 20:31:52 +02:00
Aliaksandr Valialkin
0094bc4fc9 app/vmselect/prometheus: properly adjust too big time time on /api/v1/query 
Too big `time` must be adjusted to `now()-queryOffset`.
 2019-11-19 00:42:00 +02:00
Aliaksandr Valialkin
3f1637fae8 app/vmselect/promql: properly calculate integrate(q[d]) 2019-11-13 21:10:41 +02:00
Aliaksandr Valialkin
c56b9ed03b app/victoria-metrics: add build rules for GOARCH=ppc64le 
Updates https://github.com/VictoriaMetrics/VictoriaMetrics/issues/235
 2019-11-13 20:24:33 +02:00
Aliaksandr Valialkin
3fd32e331a app/vmselect/promql: use universal approach for determining maxByteSliceLen on 32-bit and 64-bit archs 
Updates https://github.com/VictoriaMetrics/VictoriaMetrics/issues/235
 2019-11-13 20:24:26 +02:00
Aliaksandr Valialkin
119dfd01bb lib/storage: add vm_cache_size_bytes{type="storage/hour_metric_ids"} metric 2019-11-13 20:24:21 +02:00
Aliaksandr Valialkin
86a1cd700b lib/storage: remove inmemory index for recent hour, since it uses too much memory 
Production workload shows that the index requires ~4Kb of RAM per active time series.
This is too much for high number of active time series, so let's delete this index.

Now the queries should fall back to the index for the current day instead of the index
for the recent hour. The query performance for the current day index should be good enough
given the 100M rows/sec scan speed per CPU core.
 2019-11-13 17:58:07 +02:00
Aliaksandr Valialkin
c57eb0ff83 lib/storage: add -disableRecentHourIndex flag for disabling inmemory index for recent hour 
This may be useful for saving RAM on high number of time series aka high cardinality
 2019-11-13 15:02:51 +02:00
Aliaksandr Valialkin
ca259864e2 lib/storage: return back inmemory inverted index for recent hour 
Issues fixed:
- Slow startup times. Now the index is loaded from cache during start.
- High memory usage related to superflouos index copies every 10 seconds.
 2019-11-13 13:11:04 +02:00
Aliaksandr Valialkin
01bb3c06c7 lib/storage: remove inmemory inverted index for recent hours 
Production load with >10M active time series showed it could
slow down VictoriaMetrics startup times and could eat
all the memory leading to OOM.

Remove inmemory inverted index for recent hours until thorough
testing on production data shows it works OK.
 2019-11-13 10:45:53 +02:00
Aliaksandr Valialkin
6c2303764e Revert "lib/fs: do not postpone directory removal on NFS error" 
This reverts commit 4c02e496f7.

Reason for revert: the commit breaks on NFS - see https://github.com/VictoriaMetrics/VictoriaMetrics/issues/234
 2019-11-12 16:18:09 +02:00
Aliaksandr Valialkin
661dd190bb Refer to https://medium.com/@valyala/speeding-up-backups-for-big-time-series-databases-533c1a927883 from multiple places in README.md 2019-11-12 13:02:39 +02:00
Oleg Kovalov
b4f44befa3 fix misspelled words (#229) 2019-11-12 00:16:42 +02:00
Aliaksandr Valialkin
8e8f98f712 lib/storage: add tests for dateMetricIDCache 2019-11-11 13:21:57 +02:00
Aliaksandr Valialkin
56d7cc8a0d app/victoria-metrics: remove deprecated fs.MustStopDirRemover from main_test.go 2019-11-10 13:37:13 +02:00
Aliaksandr Valialkin
4c02e496f7 lib/fs: do not postpone directory removal on NFS error 
Continue trying to remove NFS directory on temporary errors for up to a minute.

The previous async removal process breaks in the following case during VictoriaMetrics start

- VictoriaMetrics opens index, finds incomplete merge transactions and starts replaying them.
- The transaction instructs removing old directories for parts, which were already merged into bigger part.
- VictoriaMetrics removes these directories, but their removal is delayed due to NFS errors.
- VictoriaMetrics scans partition directory after all the incomplete merge transactions are finished
  and finds directories, which should be removed, but weren't still removed due to NFS errors.
- VictoriaMetrics panics when it finds unexpected empty directory.

Updates https://github.com/VictoriaMetrics/VictoriaMetrics/issues/162
 2019-11-10 13:24:51 +02:00
Aliaksandr Valialkin
5c3fa59181 app/vmrestore: the upcoming release would be 1.29.0 2019-11-10 00:20:41 +02:00
Aliaksandr Valialkin
ee7765b10d lib/storage: implement per-day inverted index 2019-11-10 00:02:46 +02:00
Aliaksandr Valialkin
5810ba57c2 lib/storage: use specialized cache for (date, metricID) entries 
This improves ingestion performance.
 2019-11-09 23:06:11 +02:00
Aliaksandr Valialkin
6ad7fe8eeb lib/storage: export vm_new_timeseries_created_total metric for determining time series churn rate 2019-11-08 21:21:07 +02:00
Aliaksandr Valialkin
63b05c0b9f app/vmselect/promql: adjust memory limits calculations for incremental aggregate functions 
Incremental aggregate functions don't keep all the selected time series in memory -
they keep only up to GOMAXPROCS time series for incremental aggregations.

Take into account that the number of time series in RAM can be higher if they are split
into many groups with `by (...)` or `without (...)` modifiers.

This should reduce the number of `not enough memory for processing ... data points` false
positive errors.
 2019-11-08 21:21:07 +02:00
Aliaksandr Valialkin
d888b21657 lib/storage: add inmemory inverted index for the last hour 
It should improve performance for `last N hours` dashboards with update intervals smaller than 1 hour.
 2019-11-08 21:21:07 +02:00
Aliaksandr Valialkin
1e46961d68 app/{vmbackup,vmrestore}: add vmbackup and vmrestore tools for creating backups on s3 or gcs from instant snapshots 
Updates https://github.com/VictoriaMetrics/VictoriaMetrics/issues/203
Updates https://github.com/VictoriaMetrics/VictoriaMetrics/issues/38
 2019-11-08 21:21:07 +02:00
Aliaksandr Valialkin
e472f0b23b lib/storage: substitute error message about unsorted items in the index block after metricIDs merge with counter 
The origin of the error has been detected and documented in the code,
so it is enough to export a counter for such errors at `vm_index_blocks_with_metric_ids_incorrect_order_total`,
so it could be monitored and alerted on high error rates.

Export also the counter for processed index blocks with metricIDs - `vm_index_blocks_with_metric_ids_processed_total`,
so its' rate could be compared to `rate(vm_index_blocks_with_metric_ids_incorrect_order_total)`.
 2019-11-06 14:28:11 +02:00
Aliaksandr Valialkin
2f58f37f07 app/vmselect/promql: add lag(q[d]) function, which returns the lag between the current timestamp and the timstamp for the last data point in q 2019-11-01 12:21:33 +02:00
Aliaksandr Valialkin
d18ea0c95b app/vmstorage: add -bigMergeConcurrency and -smallMergeConcurrency flags for tuning the maximum number of CPU cores used during merges 2019-10-31 16:19:13 +02:00
Aliaksandr Valialkin
b0295dbf2e app/vmselect: add -search.latencyOffset flag for tuning the time after data collection when data points become visible in query results 
Updates https://github.com/VictoriaMetrics/VictoriaMetrics/issues/218
 2019-10-28 12:31:07 +02:00
Aliaksandr Valialkin
e83fe938c8 all: make fmt 2019-10-17 20:04:34 +03:00
Aliaksandr Valialkin
97ce4e03a5 all: add support for GOARCH=386 and fix all the issues related to 32-bit architectures such as GOARCH=arm 
Updates https://github.com/VictoriaMetrics/VictoriaMetrics/issues/212
 2019-10-17 18:23:23 +03:00
Aliaksandr Valialkin
f752479cb8 app/victoria-metrics/test: add missing docs to public funcs PopulateTimeTplString and PopulateTimeTpl 2019-10-17 00:50:46 +03:00
Aliaksandr Valialkin
61e956e175 app/victoria-metrics: add a test for max_lookback=<duration> query arg 
Updates https://github.com/VictoriaMetrics/VictoriaMetrics/issues/209
 2019-10-15 21:31:48 +03:00
Aliaksandr Valialkin
c66a691593 app/vmselect/prometheus: add -search.maxLookback command-line flag for overriding dynamic calculations for max lookback interval 
This flag is similar to `-search.lookback-delta` if set. The max lookback interval is determined dynamically
from interval between datapoints for each input time series if the flag isn't set.

The interval can be overriden on per-query basis by passing `max_lookback=<duration>` query arg to `/api/v1/query` and `/api/v1/query_range`.

Updates https://github.com/VictoriaMetrics/VictoriaMetrics/issues/209
 2019-10-15 21:31:48 +03:00
Aliaksandr Valialkin
cc21b31502 app/victoria-metrics/test: add a test for PopulateTimeTplString 2019-10-15 21:31:48 +03:00
Aliaksandr Valialkin
956fdd89d3 app/vmselect/promql: take into account the previous point when calculating max_over_time and min_over_time 
This lines up with `first_over_time` function used in `rollup_candlestick`, so `rollup=low` always returns
the minimum value.

Updates https://github.com/VictoriaMetrics/VictoriaMetrics/issues/204
 2019-10-08 12:30:05 +03:00
Artem Navoiev
1e2c511747 Add regression test for query apo 
Part of https://github.com/VictoriaMetrics/VictoriaMetrics/issues/187
cover:
- https://github.com/VictoriaMetrics/VictoriaMetrics/issues/153
- https://github.com/VictoriaMetrics/VictoriaMetrics/issues/150
 2019-10-07 22:18:04 +03:00
Artem Navoiev
a116f5e7c1 Add regression test for query apo (#194) 
Part of https://github.com/VictoriaMetrics/VictoriaMetrics/issues/187
cover:
- https://github.com/VictoriaMetrics/VictoriaMetrics/issues/184
 2019-09-30 11:25:54 +03:00
Aliaksandr Valialkin
4e9e1ca0f7 app/vmselect/netstorage: hint the OS that tmpBlocksFile is read almost sequentially 
This became the case after b7ee2e7af2 .
 2019-09-30 00:11:14 +03:00
Aliaksandr Valialkin
c1d3705be0 app/vmselect/netstorage: marshal block outside tmpBlocksFile.WriteBlock 
This allows re-using the destination buffer for marshaling in the outer loop.
 2019-09-28 21:07:13 +03:00
Aliaksandr Valialkin
b7ee2e7af2 app/vmselect/netstorage: reduce the number of disk seeks when the query processes big number of time series 2019-09-28 21:07:09 +03:00
Aliaksandr Valialkin
67d44b0845 app/vmselect/promql: do not generate timestamps for NaN values in timestamp function according to Prometheus logic 2019-09-27 18:54:43 +03:00
Artem Navoiev
1e6ae9eff4 Add regression test for duplicated labels and series 
Part of https://github.com/VictoriaMetrics/VictoriaMetrics/issues/187
cover:
- https://github.com/VictoriaMetrics/VictoriaMetrics/issues/155
- https://github.com/VictoriaMetrics/VictoriaMetrics/issues/172
 2019-09-27 16:52:16 +03:00
Artem Navoiev
cf4786f34a add test for https://github.com/VictoriaMetrics/VictoriaMetrics/issues/161 2019-09-26 12:45:19 +03:00
Aliaksandr Valialkin
26dc21cf64 app/vmselect/promql: add increases_over_time and decreases_over_time functions 
`increases_over_time(q[d])` returns the number of `q` increases during the given duration `d`.
`decreases_over_time(q[d])` returns the number of `q` decreases during the given duration `d`.
 2019-09-25 20:38:44 +03:00
Aliaksandr Valialkin
d32f88c378 app/vminsert/opentsdbhttp: remove FATAL prefix from logger.Fatalf errors for the sake of consistency with other logger.Fatalf calls 2019-09-19 22:15:59 +03:00
Aliaksandr Valialkin
d4218d27e6 app/vmselect/promql: properly handle subqueries like aggr_func(rollup_func(metric[window:step])) 
Updates https://github.com/VictoriaMetrics/VictoriaMetrics/issues/184
 2019-09-13 21:41:04 +03:00
Aliaksandr Valialkin
4d636c244d app/vmselect/promql: binary operation fixes according to Prometheus behaviour 
The follosing issues were fixed:
- VictoriaMetrics could leave superflouos labels when using `on` or `ignoring` modifiers
- VictoriaMetrics could return `duplicate timeseries` error when using `group_left` or `group_right` with non-empty label list
 2019-09-13 17:42:52 +03:00
Artem Navoiev
4fd741f40d [tests] check timestamp in tests (#177) 2019-09-08 19:48:38 +03:00
Artem Navoiev
22e3fabefd Add OpenTSDB and Prometheus integration tests (#168) 
* [WIP] open tsdb and prometheus integration tests

* app/victoria-metrics: fix race condition on parallel tests
 2019-09-05 17:55:38 +03:00
Aliaksandr Valialkin
88f8670ede lib/fs: add MustStopDirRemover for waiting until pending directories are removed on graceful shutdown 
This patch is mainly required for laggy NFS. See https://github.com/VictoriaMetrics/VictoriaMetrics/issues/162
 2019-09-05 11:13:17 +03:00