Instead of carrying around extra fields in `Meta` structs which let us
approximate what was in the chunk at the time, take a copy of the chunk.
This simplifies lots of code, and lets us correct a couple of tests which
were embedding the wrong answer.
We can also remove boundedIterator, which was only used to constrain
the OOO head chunk.
Signed-off-by: Bryan Boreham <bjboreham@gmail.com>
* expose hook for block querier
Signed-off-by: Ben Ye <benye@amazon.com>
* update comment
Signed-off-by: Ben Ye <benye@amazon.com>
* use defined type
Signed-off-by: Ben Ye <benye@amazon.com>
---------
Signed-off-by: Ben Ye <benye@amazon.com>
* Pass affected labels to MemPostings.Delete
As suggested by @bboreham, we can track the labels of the deleted series
and avoid iterating through all the label/value combinations.
This looks much faster on the MemPostings.Delete call. We don't have a
benchmark on stripeSeries.gc() where we'll pay the price of iterating
the labels of each one of the deleted series.
Signed-off-by: Oleg Zaytsev <mail@olegzaytsev.com>
* add hook to allow head compaction to create multiple output blocks
Signed-off-by: Ben Ye <benye@amazon.com>
* change Compact interface; remove BlockPopulator changes
Signed-off-by: Ben Ye <benye@amazon.com>
* rebase main
Signed-off-by: Ben Ye <benye@amazon.com>
* fix lint
Signed-off-by: Ben Ye <benye@amazon.com>
* fix unit test
Signed-off-by: Ben Ye <benye@amazon.com>
* address feedbacks; add unit test
Signed-off-by: Ben Ye <benye@amazon.com>
* Apply suggestions from code review
Signed-off-by: Ganesh Vernekar <ganeshvern@gmail.com>
* Update tsdb/compact_test.go
Signed-off-by: Ganesh Vernekar <ganeshvern@gmail.com>
---------
Signed-off-by: Ben Ye <benye@amazon.com>
Signed-off-by: Ganesh Vernekar <ganeshvern@gmail.com>
Co-authored-by: Ganesh Vernekar <ganeshvern@gmail.com>
The only call we have to LabelValuesFor() has an index.Postings, and we
expand it to pass to this method, which will iterate over the values.
That's a waste of resources: we can iterate on the index.Postings
directly.
If there's any downstream implementation that has a slice of series,
they can always do an index.ListPostings from them: doing that is
cheaper than expanding an abstract index.Postings.
Signed-off-by: Oleg Zaytsev <mail@olegzaytsev.com>
* MemPostings.PostingsForLabelMatching: let mutex go
This changes the `MemPostings.PostingsForLabelMatching` implementation
to stop holding the read mutex while matching the label values.
We've seen that this method can be slow when the matcher is expensive,
that's why we even added a context expiration check.
However, there are critical process that might be waiting on this mutex:
writes (adding new series) and compaction (deleting the
garbage-collected ones), so we should avoid holding it for a long period
of time.
Given that we've copied the values to a slice anyway, there's no need to
hold the lock while matching.
Signed-off-by: Oleg Zaytsev <mail@olegzaytsev.com>
* MemPostings: reduce locking/unlocking
MemPostings.Delete is called from Head.gc(), i.e. it gets the IDs of the
series that have churned.
I'd assume that many label values aren't affected by that churn at all,
so it doesn't make sense to touch the lock while checking them.
Signed-off-by: Oleg Zaytsev <mail@olegzaytsev.com>
It's quite common during the compaction cycle to hold series IDs for
series that aren't in the TSDB head anymore.
We shouldn't fail if that happens, as the caller has no way to figure
out which one of the IDs doesn't exist.
Fixes https://github.com/prometheus/prometheus/issues/14278
Signed-off-by: Oleg Zaytsev <mail@olegzaytsev.com>
* expose hook in tsdb to allow customizing compactor
Signed-off-by: Ben Ye <benye@amazon.com>
* address comment
Signed-off-by: Ben Ye <benye@amazon.com>
---------
Signed-off-by: Ben Ye <benye@amazon.com>
Now the error will include the timestamp and the existing and new values.
When you are trying to track down the source of this error, it can be
useful to see that the values are close, or alternating, or something
else.
Signed-off-by: Bryan Boreham <bjboreham@gmail.com>
Test with different amounts of capacity and exemplars, so that sometimes
new exemplars are evicting older exemplars.
Signed-off-by: Bryan Boreham <bjboreham@gmail.com>
Follow up on https://github.com/prometheus/prometheus/pull/14096
As promised, I bring a benchmark, which shows a very small improvement
if context is checked every 128 iterations of label instead of every
100.
It's much easier for a computer to check modulo 128 than modulo 100.
This is a very small 0-2% improvement but I'd say this is one of the
hottest paths of the app so this is still relevant.
Signed-off-by: Oleg Zaytsev <mail@olegzaytsev.com>
Followup to #14096
Unfortunately the previous PR introduced this bug by not releasing the
lock before returning.
Signed-off-by: György Krajcsovits <gyorgy.krajcsovits@grafana.com>
* tsdb: check for context cancel before regex matching postings
Regex matching can be heavy if the regex takes a lot of cycles to
evaluate and we can get stuck evaluating postings for a long time
without this fix. The constant checkContextEveryNIterations=100
may be changed later.
Signed-off-by: György Krajcsovits <gyorgy.krajcsovits@grafana.com>
Add method `PostingsForLabelMatching` to `tsdb.IndexReader`, to obtain postings for labels with a certain name and values accepted by a provided callback, and use it from `tsdb.PostingsForMatchers`.
The intention is to optimize regexp matcher paths, especially not having to load all label values before matching on them.
Plus tests, and refactor some `tsdb/index.Reader` methods.
Benchmarking shows memory reduction up to ~100%, and speedup of up to ~50%.
Signed-off-by: Arve Knudsen <arve.knudsen@gmail.com>
Co-authored-by: Bartlomiej Plotka <bwplotka@gmail.com>
use it in loadDataAsQueryable to make sure the RO Head doesn't truncate or cut new chunks in data/chunks_head/.
add a -sandbox-dir-root flag to "promtool tsdb dump/dump-openmetrics" to control the root of that sandbox dirrectory.
Signed-off-by: machine424 <ayoubmrini424@gmail.com>
Thanos can create and destroy TSDBs dynamically, and once a TSDB
disappears its files are deleted. Calculating the size of the
WAL then fails with errors like:
```
msg: "Failed to calculate size of "wal" dir", "err": "lstat
/tsdbdir/wal: no such file or directory", "caller": "wlog.go:271"
```
Signed-off-by: Giedrius Statkevičius <giedrius.statkevicius@vinted.com>
Signed-off-by: Jonathan Halterman <jonathan@grafana.com>
Signed-off-by: Jonathan Halterman <jhalterman@gmail.com>
Co-authored-by: Jesus Vazquez <jesusvazquez@users.noreply.github.com>
* Stop compactions if there's a block to write
db.Compact() checks if there's a block to write with HEAD chunks before calling db.compactBlocks().
This is to ensure that if we need to write a block then it happens ASAP, otherwise memory usage might keep growing.
But what can also happen is that we don't need to write any block, we start db.compactBlocks(),
compaction takes hours, and in the meantime HEAD needs to write out chunks to a block.
This can be especially problematic if, for example, you run Thanos sidecar that's uploading block,
which requires that compactions are disabled. Then you disable Thanos sidecar and re-enable compactions.
When db.compactBlocks() is finally called it might have a huge number of blocks to compact, which might
take a very long time, during which HEAD cannot write out chunks to a new block.
In such case memory usage will keep growing until either:
- compactions are finally finished and HEAD can write a block
- we run out of memory and Prometheus gets OOM-killed
This change adds a check for pending HEAD block writes inside db.compactBlocks(), so that
we bail out early if there are still compactions to run, but we also need to write a new
block.
Also add a test for compactBlocks.
---------
Signed-off-by: Łukasz Mierzwa <l.mierzwa@gmail.com>
Signed-off-by: Lukasz Mierzwa <lukasz@cloudflare.com>
* Use single bit to differentiate between optimized bounds and floats
Use one bit to decide what kind of data to read/write.
This reduces storage need of floats from 72 bits to 65 bits and makes the
integers store in 5 to 32 bits instead of 16.
Signed-off-by: György Krajcsovits <gyorgy.krajcsovits@grafana.com>
Signed-off-by: Jeanette Tan <jeanette.tan@grafana.com>
Signed-off-by: György Krajcsovits <gyorgy.krajcsovits@grafana.com>
Signed-off-by: Jeanette Tan <jeanette.tan@grafana.com>
Signed-off-by: George Krajcsovits <krajorama@users.noreply.github.com>
Co-authored-by: Jeanette Tan <jeanette.tan@grafana.com>
* TSDB: Don't compact the head block when empty
Don't compact the Head block if there have not yet been any samples
appended.
Previously, the logic for determining if the head should be compacted
relied on the default values for min and max time and integer overflow
when they were checked in `Head.compactable()`. The check in
`Head.compactable()` effectively did `math.MinInt64 - math.MaxInt64`
which overflowed and wrapped to `1`. Since `1` is less than `1.5`
times the chunk range, compaction did not happen. This was the correct
behavior but relying on overflow wrapping is surprising.
This change add a method for checking if the min and max time for the
head is unset and uses it to short-circuit compaction in that case.
It also replaces several explicit checks for the default value to
determine if the head has not yet had any samples added.
Signed-off-by: Nick Pillitteri <nick.pillitteri@grafana.com>
* tsdb: zero out Labels and memSeries pointers in pool
So that the garbage-collector doesn't see this memory as still in use.
Signed-off-by: Bryan Boreham <bjboreham@gmail.com>
---------
Signed-off-by: Bryan Boreham <bjboreham@gmail.com>
Signed-off-by: Björn Rabenstein <github@rabenste.in>
Co-authored-by: Björn Rabenstein <github@rabenste.in>
Dogfood native histograms.
Allow dependent projects to migrate to native histograms.
I took the defaults from client_golang.
Signed-off-by: György Krajcsovits <gyorgy.krajcsovits@grafana.com>
Clarify in the first comment that it is `watch()` that waits, and reduce
verbiage.
The second comment was slightly contradictory to the first and otherwise
didn't seem to add much, since `currentSegment` was incremented just a
few lines later.
Signed-off-by: Bryan Boreham <bjboreham@gmail.com>
* fix bug that would cause us to only read from the WAL on the 15s
fallback timer if remote write had fallen behind and is no longer
reading from the WAL segment that is currently being written to
Signed-off-by: Callum Styan <callumstyan@gmail.com>
* remove unintended logging, fix lint, plus allow test to take slightly
longer because cloud CI
Signed-off-by: Callum Styan <callumstyan@gmail.com>
* address review feedback
Signed-off-by: Callum Styan <callumstyan@gmail.com>
* fix watcher sleeps in test, flu brain is smooth
Signed-off-by: Callum Styan <callumstyan@gmail.com>
* increase timeout, unfortunately cloud CI can require a longer timeout
Signed-off-by: Callum Styan <callumstyan@gmail.com>
---------
Signed-off-by: Callum Styan <callumstyan@gmail.com>
For instance `require.NoError` will print the unexpected error; we don't
need to include it in the message.
Signed-off-by: Bryan Boreham <bjboreham@gmail.com>
'defer' runs at the end of the whole function; we should close each
segment file as soon as we finished reading it.
Signed-off-by: Bryan Boreham <bjboreham@gmail.com>
This PR is a reference implementation of the proposal described in #10420.
In addition to what described in #10420, in this PR I've introduced labels.StableHash(). The idea is to offer an hashing function which doesn't change over time, and that's used by query sharding in order to get a stable behaviour over time. The implementation of labels.StableHash() is the hashing function used by Prometheus before stringlabels, and what's used by Grafana Mimir for query sharding (because built before stringlabels was a thing).
Follow up work
As mentioned in #10420, if this PR is accepted I'm also open to upload another foundamental piece used by Grafana Mimir query sharding to accelerate the query execution: an optional, configurable and fast in-memory cache for the series hashes.
Signed-off-by: Marco Pracucci <marco@pracucci.com>
Mutex is 8 bytes; RWMutex is 24 bytes and much more complicated. Since
`RLock` is only used in two places, `UpdateMetadata` and `Delete`,
neither of which are hotspots, we should use the cheaper one.
Signed-off-by: Bryan Boreham <bjboreham@gmail.com>
Lifting an optimisation from Agent code, `seriesHashmap.del` can use
the unique series reference, doesn't need to check Labels.
Also streamline the logic for deleting from `unique` and `conflicts` maps,
and add some comments to help the next person.
Signed-off-by: Bryan Boreham <bjboreham@gmail.com>
Add test case to TestHeadLabelValuesWithMatchers, while fixing a couple
of typos in other test cases. Also enclosing some implicit sub-tests in a
`t.Run` call to make them explicitly sub-tests.
Signed-off-by: Arve Knudsen <arve.knudsen@gmail.com>
Optimize histogram iterators
Histogram iterators allocate new objects in the AtHistogram and
AtFloatHistogram methods, which makes calculating rates over long
ranges expensive.
In #13215 we allowed an existing object to be reused
when converting an integer histogram to a float histogram. This commit follows
the same idea and allows injecting an existing object in the AtHistogram and
AtFloatHistogram methods. When the injected value is nil, iterators allocate
new histograms, otherwise they populate and return the injected object.
The commit also adds a CopyTo method to Histogram and FloatHistogram which
is used in the BufferedIterator to overwrite items in the ring instead of making
new copies.
Note that a specialized HPoint pool is needed for all of this to work
(`matrixSelectorHPool`).
---------
Signed-off-by: Filip Petkovski <filip.petkovsky@gmail.com>
Co-authored-by: George Krajcsovits <krajorama@users.noreply.github.com>
Don't calculate postings beforehand: we may not need them. If all
matchers are for the requested label, we can just filter its values.
Also, if there are no values at all, no need to run any kind of
logic.
Also add more labelValuesWithMatchers benchmarks
Signed-off-by: Oleg Zaytsev <mail@olegzaytsev.com>
This functionality is needed in downstream projects because they have a
separate component that does compaction.
Upstreaming
7c8e9a2a76/tsdb/compact.go (L323-L325).
Signed-off-by: Giedrius Statkevičius <giedrius.statkevicius@vinted.com>
* tsdb/{index,compact}: allow using custom postings encoding format
We would like to experiment with a different postings encoding format in
Thanos so in this change I am proposing adding another argument to
`NewWriter` which would allow users to change the format if needed.
Also, wire the leveled compactor so that it would be possible to change
the format there too.
Signed-off-by: Giedrius Statkevičius <giedrius.statkevicius@vinted.com>
* tsdb/compact: use a struct for leveled compactor options
As discussed on Slack, let's use a struct for the options in leveled
compactor.
Signed-off-by: Giedrius Statkevičius <giedrius.statkevicius@vinted.com>
* tsdb: make changes after Bryan's review
- Make changes less intrusive
- Turn the postings encoder type into a function
- Add NewWriterWithEncoder()
Signed-off-by: Giedrius Statkevičius <giedrius.statkevicius@vinted.com>
---------
Signed-off-by: Giedrius Statkevičius <giedrius.statkevicius@vinted.com>
This reverts commit 2ddb3596ef.
Various tests are failing in CI after this change; reverting to free up
other work.
Signed-off-by: Bryan Boreham <bjboreham@gmail.com>
They are used in multiple repos, so common is a better place for them.
Several packages now don't depend on `model/textparse`, e.g.
`storage/remote`.
Also remove `metadata` struct from `api.go`, since it was identical to
a struct in the `metadata` package.
Signed-off-by: Bryan Boreham <bjboreham@gmail.com>
In https://github.com/prometheus/prometheus/pull/13276 we started reusing float histogram objects to reduce allocations in PromQL.
That PR introduces a bug where histogram pointers gets copied to the beginning of the histograms slice,
but are still kept in the end of the slice. When a new histogram is read into the last element,
it can overwrite a previous element because the pointer is the same.
This commit fixes the issue by moving outdated points to the end of the slice
so that we don't end up with duplicate pointers in the same buffer. In other words,
the slice gets rotated so that old objects can get reused.
Signed-off-by: Filip Petkovski <filip.petkovsky@gmail.com>
