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197 commits

Author SHA1 Message Date
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
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
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
cea5a14853 all: rename Extended PromQL to PromQL extensions 2019-12-12 19:25:58 +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
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
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
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
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
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
Oleg Kovalov
b4f44befa3 fix misspelled words (#229) 2019-11-12 00:16:42 +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
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
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
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
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
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
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
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
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
Aliaksandr Valialkin
6954e126fc app/vmselect/promql: ignore grouping by destination label in count_values, since such a grouping is performed automatically 2019-09-04 19:58:01 +03:00
Aliaksandr Valialkin
305e7bc981 app/vmselect/promql: do not return artificial points beyond the last point in time series 2019-09-04 16:35:34 +03:00
Aliaksandr Valialkin
9721d06c6a app/vmselect/prometheus: do not adjust start and end args in /api/v1/query_range if nocache=1 arg is set 
Updates https://github.com/VictoriaMetrics/VictoriaMetrics/issues/171
 2019-09-04 13:10:09 +03:00
Aliaksandr Valialkin
db4560ca31 app/vmselect/promql: reset timeseries name on group_left and group_right as Prometheus does 2019-09-03 20:42:54 +03:00
Aliaksandr Valialkin
1575a560f0 app/vmselect/netstorage: adaptively adjust the maximum inmemory file size for storing temporary blocks 
The maximum inmemory file size now depends on `-memory.allowedPercent`.
This should improve performance and reduce the number of filesystem calls
on machines with big amounts of RAM when performing heavy queries
over big number of samples and time series.
 2019-09-03 13:32:09 +03:00
Aliaksandr Valialkin
9196c085a7 all: port to FreeBSD on GOARCH=amd64 2019-08-28 01:19:23 +03:00
Aliaksandr Valialkin
603a79b357 app/vmstorage: increase default values for search.maxTagKeys, search.maxTagValues and search.maxUniqueTimeseries 2019-08-27 14:29:53 +03:00
Aliaksandr Valialkin
ac004665b5 all: return 503 http error if service is temporarily unavailable 
Updates https://github.com/VictoriaMetrics/VictoriaMetrics/issues/156
 2019-08-23 09:55:07 +03:00
Aliaksandr Valialkin
1272e407b2 app/vmselect/promql: attempt to repair invalid bucket counts passed to histogram_quantile 
Updates https://github.com/VictoriaMetrics/VictoriaMetrics/issues/136
Updates https://github.com/VictoriaMetrics/VictoriaMetrics/issues/154
 2019-08-22 14:39:46 +03:00
Aliaksandr Valialkin
f4a38f7fb1 app/vmselect/promql: fix panic on -search.disableCache 
Reset the cache if it is disabled instead of stopping, since it is stopped on graceful shutdown.
 2019-08-21 17:11:52 +03:00
Aliaksandr Valialkin
ab740afd0d app/vmselect/promql: explain why empty timeseries arent removed in transformLabelValue 2019-08-21 11:29:24 +03:00
Aliaksandr Valialkin
7b5168adfb app/vmselect/promql: remove NaNs from /api/v1/query_range output like Prometheus does 
Updates https://github.com/VictoriaMetrics/VictoriaMetrics/issues/153
 2019-08-20 23:01:41 +03:00
Aliaksandr Valialkin
a0d480fbf3 app/vmselect/promql: pre-allocate memory for map for checking for duplicate timeseries 
This should reduce memory allocations for big number of timeseries
 2019-08-20 23:01:39 +03:00
Aliaksandr Valialkin
d3fd113a80 app/vmselect/promql: add label_value(q, label_name) func, which returns numeric value labels with name label_name in q 2019-08-20 00:28:34 +03:00
Aliaksandr Valialkin
dd86e6130c app/vmselect/promql: independently track offset hints for tStart and tEnd 
This should improve performance if timeseries starts or ends on the selected time range
 2019-08-19 13:40:14 +03:00
Aliaksandr Valialkin
6a27657d73 app/vmselect/promql: optimize search for timestamp boundaries in rollupConfig.Do 
This should improve the performance of queries over big number of time series
with big number of output points.
 2019-08-19 13:03:29 +03:00
Aliaksandr Valialkin
e74fb23189 app/vmselect/promql: add scrape_interval(q[d]) function, which would return scrape interval for q over d 2019-08-18 21:08:26 +03:00
Aliaksandr Valialkin
582fdc059a app/vmselect/promql: hande comparisons with NaN similar to Prometheus 
Updates https://github.com/VictoriaMetrics/VictoriaMetrics/issues/150
 2019-08-18 00:25:50 +03:00
Aliaksandr Valialkin
1c108fc494 app/vmselect/promql: add lifetime(q[d]) function, which returns the lifetime of q over d in seconds. 
This function is useful for determining time series lifetime.
`d` must exceed the expected lifetime of the time series, otherwise
the function would return values close to `d`.
 2019-08-16 11:59:32 +03:00
Aliaksandr Valialkin
d6b5ed6d39 app/vmselect/promql: fix corner-case calculation for ideriv 2019-08-16 11:59:28 +03:00
Aliaksandr Valialkin
639b14e8ab app/vmselect/promql: properly handle corner cases for rollup functions 2019-08-15 23:29:59 +03:00
Aliaksandr Valialkin
9ecb994671 app/vmselect/promql: store compressed results in the cache 
This should increase rollup results cache capacity.
 2019-08-14 02:29:45 +03:00
Aliaksandr Valialkin
09fc6e22e5 all: use workingsetcache instead of fastcache 
This should reduce the amount of RAM required for processing time series
with non-zero churn rate.

The previous cache behavior can be restored with `-cache.oldBehavior` command-line flag.
 2019-08-13 21:39:34 +03:00
Aliaksandr Valialkin
5c83f8e203 app: add vm_concurrent_ metrics for visibility in concurrency limiters for vminsert and vmselect 2019-08-05 18:30:57 +03:00
Aliaksandr Valialkin
99e048c9df app/vmselect: allow passing match[], start and time to /api/v1/label/<label_name>/values 
`/api/v1/label/<label_name>/values?match[]=q` emulates emulates `label_values(q, <label_name>)`
call in Grafana templating.
 2019-08-04 23:09:21 +03:00
Aliaksandr Valialkin
47e4b50112 app/vmselect: optimize /api/v1/series by skipping storage data 
Fetch and process only time series metainfo.
 2019-08-04 23:01:28 +03:00
Aliaksandr Valialkin
241170dc05 app/vmselect/prometheus: prevent from fetching and scanning all the data on /api/v1/searies call by default 2019-08-04 19:42:36 +03:00
Aliaksandr Valialkin
1c69f4eadc app/vmselect/promql: tune automatic window adjustement 
Increase the windows adjustement for small scrape intervals,
since they usually have higher jitter.

Updates https://github.com/VictoriaMetrics/VictoriaMetrics/issues/139
Updates https://github.com/VictoriaMetrics/VictoriaMetrics/issues/134
 2019-08-04 19:34:05 +03:00
Aliaksandr Valialkin
8d93b15b86 app/vmselect/promql: further increase the allowed jitter for scrape interval 
Real-world production data shows higher jitter than 1/8 of scrape interval.
This may results in gaps on the graph. So increase the allowed jitter to 1/4
of scrape interval in order to reduce the probability of gaps on the graphs
over time series with high jitter for scrape_interval.
 2019-08-02 20:10:23 +03:00
Aliaksandr Valialkin
f090b2e917 app/vmselect/promql: tolerate higher jitter in scrape interval 
Allow jitter for up to 1/8 instead of 1/16 for the scrape interval.
This should imrpove graphs when `step` is smaller than the `scrape_interval`.
 2019-08-01 23:26:00 +03:00
Aliaksandr Valialkin
3a38b23fa3 app/vmselect/promql: add vm_slow_queries_total metric for counting slow queries 
The query is slow if its execution time exceeds `-search.logSlowQueryDuration`
 2019-07-31 03:36:37 +03:00
Aliaksandr Valialkin
8bd6f1f6df app/vmselect/promql: return NaN from histogram_quantile if at least a single bucket is broken 2019-07-31 01:18:07 +03:00
Aliaksandr Valialkin
4aaa5c2efc app/vmselect/promql: allow adjusting window for default rollup function 
Default rollup function is `last_over_time`. It must support adjusting
the provided window in order to prevent from gaps on the graph
for window values smaller than scrape interval.

Updates https://github.com/VictoriaMetrics/VictoriaMetrics/issues/134
 2019-07-31 00:45:54 +03:00
Aliaksandr Valialkin
10f5a26bec app/vmselect/promql: return NaN values if invalid bucket counts are passed to histogram_quantile 
Updates https://github.com/VictoriaMetrics/VictoriaMetrics/issues/136
 2019-07-30 22:05:10 +03:00
Aliaksandr Valialkin
afcc7fb167 app/vmselect/netstorage: improve error message when reading data blocks from storage 
Mention the block number in the error. This should simplify troubleshooting in this code.
 2019-07-28 12:12:35 +03:00
Aliaksandr Valialkin
17096b5750 app/vmselect/promql: return NaN from count() over zero time series 
This aligns `count` behavior with Prometheus.
 2019-07-25 22:02:30 +03:00
Aliaksandr Valialkin
66efa5745f app/vmselect/promql: properly calculate incremental aggregations grouped by __name__ 
Previously the following query may fail on multiple distinct metric names match:

    sum(count_over_time{__name__!=''}) by (__name__)
 2019-07-25 21:53:20 +03:00
Aliaksandr Valialkin
6a943a6a58 app/vmselect/promql: remove empty time series after applying filters like q > 0 
This should reduce CPU and RAM usage for queries over high number of time series.
 2019-07-12 19:59:27 +03:00
Aliaksandr Valialkin
ab88890523 app/vmselect/promql: parallelize incremental aggregation to multiple CPU cores 
This may reduce response times for aggregation over big number of time series
with small step between output data points.
 2019-07-12 15:52:22 +03:00
Aliaksandr Valialkin
62a7353479 app/vmselect/prometheus: set start arg in /api/v1/series to the minimum allowed time by default as Prometheus does 
Fixes https://github.com/VictoriaMetrics/VictoriaMetrics/issues/91
 2019-07-11 17:10:14 +03:00
Aliaksandr Valialkin
54bd21eb4a app/vmselect/prometheus: convert negative times to 0, since they arent supported by the storage 2019-07-11 17:07:20 +03:00
Aliaksandr Valialkin
a336bb4e22 app/vmselect/promql: reduce RAM usage for aggregates over big number of time series 
Calculate incremental aggregates for `aggr(metric_selector)` function instead of
keeping all the time series matching the given `metric_selector` in memory.
 2019-07-10 13:04:39 +03:00
Aliaksandr Valialkin
1fe6d784d8 all: consistency renaming: bytesSize -> sizeBytes 2019-07-10 00:47:36 +03:00
Aliaksandr Valialkin
55fe36149c app/vmselect/promql: mention -search.logSlowQueryDuration flag value in the slow query log message 2019-07-10 00:41:24 +03:00
Aliaksandr Valialkin
9203170eb2 app/vmselect/promql: extract rmoeveGroupTags function for removing unneeded tags from MetricName according to the given modifierExpr 2019-07-09 23:20:48 +03:00
Aliaksandr Valialkin
2db685c19c app/vmselect/promql: properly preserve metric name after applying functions in any case from transformFuncsKeepMetricGroup 2019-07-09 23:10:35 +03:00
Aliaksandr Valialkin
40a6c0d672 app/vmselect/prometheus: typo fix 2019-07-07 23:34:23 +03:00
Aliaksandr Valialkin
1371024747 app/vmselect/prometheus: handle minTime and maxTime values that may be set by Promxy or Prometheus client 
Fixes https://github.com/VictoriaMetrics/VictoriaMetrics/issues/88
 2019-07-07 21:53:48 +03:00
Aliaksandr Valialkin
4dbd642c86 app/vmselect/promql: remove empty timeseries left after topk call 2019-07-04 19:42:39 +03:00
Aliaksandr Valialkin
9a4b2b8315 app/vmselect/prometheus: update adjustLastPoints function 
- Do not overwrite last points by the previous NaNs, since this may result in empty time series.
- Overwrite the last 2 points instead of 3. This should be enough in most cases.
 2019-07-04 09:14:18 +03:00
Aliaksandr Valialkin
e06866005d app/vmselect/promql: gracefully handle duplicate timestamps in irate and rollup_rate funcs 
Previously such timestamps result in `+Inf` results. Now the previous timestamp is used
for the calculations.
 2019-07-03 12:39:55 +03:00