### Describe Your Changes
In most cases histograms are exposed in sorted manner with lower buckets
being first. This means that during scraping buckets with lower bounds
have higher chance of being updated earlier than upper ones.
Previously, values were propagated from upper to lower bounds, which
means that in most cases that would produce results higher than expected
once all buckets will become updated.
Propagating from upper bound effectively limits highest value of
histogram to the value of previous scrape. Once the data will become
consistent in the subsequent evaluation this causes spikes in the
result.
Changing propagation to be from lower to higher buckets reduces value
spikes in most cases due to nature of the original inconsistency.
See: https://github.com/VictoriaMetrics/VictoriaMetrics/issues/4580
An example histogram with previous(red) and updated(blue) versions:
![1719565540](https://github.com/VictoriaMetrics/VictoriaMetrics/assets/1367798/605c5e60-6abe-45b5-89b2-d470b60127b8)
This also makes logic of filling nan values with lower buckets values: [1 2 3 nan nan nan] => [1 2 3 3 3 3] obsolete.
Since buckets are now fixed from lower ones to upper this happens in the main loop, so there is no need in a second one.
---------
Signed-off-by: Zakhar Bessarab <z.bessarab@victoriametrics.com>
Signed-off-by: hagen1778 <roman@victoriametrics.com>
Co-authored-by: Andrii Chubatiuk <andrew.chubatiuk@gmail.com>
Co-authored-by: hagen1778 <roman@victoriametrics.com>
(cherry picked from commit 6a4bd5049b)
'any' type is supported starting from Go1.18. Let's consistently use it
instead of 'interface{}' type across the code base, since `any` is easier to read than 'interface{}'.
Use metricsql.IsLikelyInvalid() function for determining whether the given query is likely invalid,
e.g. there is high change the query is incorrectly written, so it will return unexpected results.
The query is invalid most of the time if it passes something other than series selector into rollup function.
For example:
- rate(sum(foo))
- rate(foo + bar)
- rate(foo > bar)
Improtant note: the query is considered valid if it misses the lookbehind window in square brackes inside rollup function,
e.g. rate(foo), since this is very convenient MetricsQL extention to PromQL, and this query returns the expected results
most of the time.
Other unsafe query types can be added in the future into metricsql.IsLikelyInvalid().
TODO: probably, the -search.disableImplicitConversion command-line flag must be set by default in the future releases of VictoriaMetrics.
Updates https://github.com/VictoriaMetrics/VictoriaMetrics/issues/4338
Updates https://github.com/VictoriaMetrics/VictoriaMetrics/pull/6180
Updates https://github.com/VictoriaMetrics/VictoriaMetrics/pull/6450
This reverts commit 5ecf439078.
Reason for revert: the previous logic was correct.
The purpose of `-search.maxSamplesPerQuery` command-line flag is to limit the amounts of CPU resources,
which could be taken by a single query - see https://docs.victoriametrics.com/#resource-usage-limits .
VictoriaMetrics processes samples in blocks during querying - it reads the block, then unpacks it,
then filters out samples outside the selected time range. This means that it _spends CPU time_
on reading and unpacking of _all the samples_ in every block on the requested time range,
even if only a single sample per each block matches the given time range.
The previous logic was effectively limiting CPU time a single query could take.
The new logic fails limiting CPU time a single query could take in some pathological cases
when only a small fraction of samples per each requested block fit the requested time range.
This allows performing multiplication DoS-attacks by querying very narrow time ranges over historical blocks,
which tend to be full. For example, if the `-search.maxSamplesPerQuery` equals to a billion,
and the query requests a single sample out of 8K samples per each block, this means that the query
may unpack a billion of such blocks without exceeding the limit, e.g. it may unpack and process 8K*1e9=8e12 samples.
This is not what the resource usage limits were created for originally - see https://docs.victoriametrics.com/#resource-usage-limits
Updates https://github.com/VictoriaMetrics/VictoriaMetrics/issues/5851
Updates https://github.com/VictoriaMetrics/VictoriaMetrics/pull/6464
Check for ranged vector arguments in aggregate expressions when
`-search.disableImplicitConversion` or `-search.logImplicitConversion`
are enabled.
For example, `sum(up[5m])` will fail to execute if these flags are set.
### Describe Your Changes
Please provide a brief description of the changes you made. Be as
specific as possible to help others understand the purpose and impact of
your modifications.
### Checklist
The following checks are **mandatory**:
- [*] My change adheres [VictoriaMetrics contributing
guidelines](https://docs.victoriametrics.com/contributing/).
---------
Signed-off-by: hagen1778 <roman@victoriametrics.com>
(cherry picked from commit 6149adbe10)
The limit is specified with command-line flag
`-search.maxSamplesPerQuery`.
Previously, samples might be over-counted and query can't be fixed by
reducing time range.
address https://github.com/VictoriaMetrics/VictoriaMetrics/issues/5851
(cherry picked from commit 6e395048d3)
Signed-off-by: hagen1778 <roman@victoriametrics.com>
Update wording to highlight that cache is not persistent if flag is
value is empty. Previously, it was not clear if cache is not used at all
or just not persistent.
### Describe Your Changes
Added makefile rule for `GOARCH=loong64` to support building all
VictoriaMetrics components on the `loongarch64` platform.
### Checklist
The following checks are **mandatory**:
* [X] My change adheres [VictoriaMetrics contributing
guidelines](https://docs.victoriametrics.com/contributing/).
Signed-off-by: qiangxuhui <qiangxuhui@loongson.cn>
(cherry picked from commit 80f3644ee3)
Signed-off-by: hagen1778 <roman@victoriametrics.com>
- Fix docs for new functions at app/vmselect/graphite/functions.json
- Properly drain series lists on errors in aggregateSeriesListsGeneric() and aggregateSeriesList()
- Add links to docs for the added functions at docs/CHANGELOG.md
Updates https://github.com/VictoriaMetrics/VictoriaMetrics/pull/5809
This reverts commit cb23685681.
Reason for revert: the "fix" may hide programming bugs related to incorrect creation of folders
before their use. This may complicate detecting and fixing such bugs in the future.
There are the following fixes for the issue https://github.com/VictoriaMetrics/VictoriaMetrics/issues/5985 :
- To configure the OS to do not drop data from the system-wide temporary directory (aka /tmp).
- To run VictoriaMetrics with -cacheDataPath command-line flag, which points to the directory,
which cannot be removed automatically by the OS.
The case when the user accidentally deletes the directory with some files created by VictoriaMetrics
shouldn't be considered as expected, so VictoriaMetrics shouldn't try resolving this case automatically.
It is much better from operation and debuggability PoV is to crash with the clear `directory doesn't exist` error
in this case.
vmselect uses a cache folder in file system for two purposes:
1. Storing rollup cache results on shutdown;
2. Storing temporary search results from vmstorage during query executions.
It could happen that cache folder is deleted accidentally by user, or by OS
during cleanup routines. This would cause vmselect to:
1. panic on /metrics call, because `MustGetFreeSpace` will fail;
2. return query error user, as it won't be able to store temporary search results.
The changes in this commit are the following:
1. Make `MustGetFreeSpace` to try re-creating the cache folder if it is missing;
2. Make vmselect to try re-creating the cache folder if it can't persist tmp search
results.
https://github.com/VictoriaMetrics/VictoriaMetrics/issues/5985
Signed-off-by: hagen1778 <roman@victoriametrics.com>
Co-authored-by: Nikolay <nik@victoriametrics.com>
(cherry picked from commit cb23685681)
The `match[]` filter is mandatory at /api/v1/series, so it mustn't be dropped here.
There is no sense in dropping `match[]` filter together with `extra_label` and `extra_filters[]`
at /api/v1/labels and /api/v1/label/.../values if -search.ignoreExtraFiltersAtLabelsAPI commnad-line flag is set,
since:
- the `match[]` filter triggers slow path at these APIs;
- the `extra_label` and `extra_filters[]` filters narrow down the number of matched time series,
so they improve performance comparing to the case when only `match[]` filter is left,
while `extra_label` and `extra_filters[]` filters are dropped.
This is a follow-up for 0b7a23a91d
The match[] at /api/v1/labels and /api/v1/label/.../values also may lead to slow requests and
high resource usage if it matches big number of time series. So it must be igrnored if -search.ignoreExtraFiltersAtLabelsAPI
command-line flag is set.
This is a follow-up for fab02faa3f
* metricsql: fix label_join() when `dst_label` is equal to one of the `src_label`
* Update app/vmselect/promql/transform.go
* Update docs/CHANGELOG.md
---------
Co-authored-by: Aliaksandr Valialkin <valyala@victoriametrics.com>
Prevsiously they were swapped - the first arg should be the label name and the second arg should be label filters
This is a follow-up for e389b7b959e8144fdff5075bf7a5a39b2b0c6dd3
Updates https://github.com/VictoriaMetrics/VictoriaMetrics/issues/5847
This commit returns back limits for these endpoints, which have been removed at 5d66ee88bd ,
since it has been appeared that missing limits result in high CPU usage, while the introduced concurrency limiter
results in failed lightweight requests to these endpoints because of timeout when heavyweight requests are executed.
Updates https://github.com/VictoriaMetrics/VictoriaMetrics/issues/5055
* app/vmselect: adds milliseconds to the csv export response for rfc3339
* milliseconds is a standard prescion for VictoriaMetrics query request responses
https://github.com/VictoriaMetrics/VictoriaMetrics/issues/5837
* app/victoria-metrics: adds tests for csv export/import
follow-up after 3541a8d0cf96dd4f8563624c4aab6816615d0756
---------
Signed-off-by: hagen1778 <roman@victoriametrics.com>
Co-authored-by: hagen1778 <roman@victoriametrics.com>