Repeated instant queries with long lookbehind windows, which contain one of the following rollup functions,
are optimized via partial result caching:
- sum_over_time()
- count_over_time()
- avg_over_time()
- increase()
- rate()
The basic idea of optimization is to calculate
rf(m[d] @ t)
as
rf(m[offset] @ t) + rf(m[d] @ (t-offset)) - rf(m[offset] @ (t-d))
where rf(m[d] @ (t-offset)) is cached query result, which was calculated previously
The offset may be in the range of up to 1 hour.
The new metric gets increased each time `-search.logQueryMemoryUsage` memory limit
is exceeded by a query. This metric should help to identify expensive and heavy queries
without inspecting the logs.
Signed-off-by: hagen1778 <roman@victoriametrics.com>
* app/vmselect: limit the number of parallel workers by 32
The change should improve performance and memory usage during query processing
on machines with big number of CPU cores. The number of parallel workers for
query processing is controlled via `-search.maxWorkersPerQuery` command-line flag.
By default, the number of workers is limited by the number of available CPU cores,
but not more than 32. The limit can be increased via `-search.maxWorkersPerQuery`.
Signed-off-by: hagen1778 <roman@victoriametrics.com>
* wip
- The `-search.maxWorkersPerQuery` command-line flag doesn't limit resource usage,
so move it from the `resource usage limits` to `troubleshooting` chapter at docs/Single-server-VictoriaMetrics.md
- Make more clear the description for the `-search.maxWorkersPerQuery` command-line flag
- Add the description of `-search.maxWorkersPerQuery` to docs/Cluster-VictoriaMetrics.md
- Limit the maximum value, which can be passed to `-search.maxWorkersPerQuery`, to GOMAXPROCS,
because bigger values may worsen query performance and increase CPU usage
- Improve the the description of the change at docs/CHANGELOG.md. Mark it as FEATURE instead of BUGFIX,
since it is closer to a feature than to a bugfix.
Updates https://github.com/VictoriaMetrics/VictoriaMetrics/issues/5087
---------
Signed-off-by: hagen1778 <roman@victoriametrics.com>
Co-authored-by: Aliaksandr Valialkin <valyala@victoriametrics.com>
This can be useful in the following queries:
drop_empty_series(temperature <= 30) default 40
This query drops temperature series with all the values bigger than 30 on the selected time range,
while replacing gaps in the remaining series with 40.
The query without drop_empty_series:
(temperature <= 30) default 40
would leave all the temperature series with all the values bigger than 30 on the selected time range,
and replace all their values with 40. This is not what could be epxected in some cases
like here - https://github.com/VictoriaMetrics/VictoriaMetrics/issues/5071
- Reduce vertical space usage, so more information is available on the screen without the need to scroll.
- Show information for lines with higher values at the top of the legend under the graph.
This should simplify graph analysis when it contains many lines.
reduce lock contention for heavy aggregation requests
previously lock contetion may happen on machine with big number of CPU due to enabled string interning. sync.Map was a choke point for all aggregation requests.
Now instead of interning, new string is created. It may increase CPU and memory usage for some cases.
https://github.com/VictoriaMetrics/VictoriaMetrics/issues/5087
`median_over_time` is handled by predefined WITH template in MetricsQL library which translates it to `quantile_over_time(0.5)`
This makes it impossble to use `median_over_time` as a usual rollup function for `aggr_over_time`.
See: https://github.com/VictoriaMetrics/VictoriaMetrics/issues/5034
Signed-off-by: Zakhar Bessarab <z.bessarab@victoriametrics.com>
* Add button to prettify query
Just capitalizes query text for now
* Add /prettify-query API handler
* Replace UI pretiffier using prettifier API
* Add showing server errors
Had to pass setQueryErrors from useFetchQuery.ts
* Use serverUrl from global AppState
* Change icon to AutoAwsome icon + added style change color when button is active
* Add sync/await to prettifyQuery function
* Doc public function for lint
* Minor async fix
* Removed extra blank lines
* Extract usePrettifyQuery hook
* Made more generic style for :active button
* Refactor usePrettifyQuery
However, prettify errors don't clean up query errors, but should
* Add prettyQuery functionality to CHANGELOG.md
* Reuse queryErrors
* Unhide errors on start
---------
Co-authored-by: Tamara <toma.vashchuk@gmail.com>
This reverts commit 252643d100.
Reason for revert: the commit incorrectly fixes the the issue.
The `remoteAddr` must be properly quoted inside lib/httpserver.GetQuotedRemoteAddr().
It isn't quoted properly if the request contains X-Forwarded-For header.
The proper fix will be included in the follow-up commit.
Updates https://github.com/VictoriaMetrics/VictoriaMetrics/pull/4676
This eliminates the need in .(*T) casting for results obtained from Load()
Leave atomic.Value for map, since atomic.Pointer[map[...]...] makes double pointer to map,
because map is already a pointer type.
- Add `Active queries` chapter to VMUI docs
- Set `Content-Type: json` header inside promql.WriteActiveQueries() handler,
in order to be consistent with other request handlers called at app/vmselect/main.go
- Pass the request to promql.WriteActiveQueries() handler, so it can change its output
depending on the provided request params. This also improves consistency of
promql.WriteActiveQueries() args with other request hanlers at app/vmselect/main.go
Updates https://github.com/VictoriaMetrics/VictoriaMetrics/pull/4653
* feat: add page to display a list of active queries (#4598)
* app/vmagent: code formatting
* fix: remove console
---------
Co-authored-by: dmitryk-dk <kozlovdmitriyy@gmail.com>
The `a op b keep_metric_names` is ambigouos to `a op (b keep_metric_names)` when `b` is a transform or rollup function.
For example, `a + rate(b) keep_metric_names`. So it is better to use more clear syntax: `(a op b) keep_metric_names`
Updates https://github.com/VictoriaMetrics/VictoriaMetrics/issues/3710
