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>
Prometheus is hard-coded to use a fanout storage between TSDB and
a remote storage which by default is empty.
This change detects the empty storage and skips merging between
result sets, which would make `Select()` sort results.
Bottom line: we skip a sort unless there really is some remote storage
configured.
Signed-off-by: Bryan Boreham <bjboreham@gmail.com>
The ChunkReader interface's Chunk() has been changed to ChunkOrIterable().
This is a precursor to OOO native histogram support - with OOO native histograms, the chunks.Meta passed to Chunk() can result in multiple chunks being returned rather than just a single chunk (e.g. if oooMergedChunk has a counter reset in the middle).
To support this, ChunkOrIterable() requires either a single chunk or an iterable to be returned. If an iterable is returned, the caller has the responsibility of converting the samples from the iterable into possibly multiple chunks. The OOOHeadChunkReader now returns an iterable rather than a chunk to prepare for the native histograms case. Also as a beneficial side effect, oooMergedChunk and boundedChunk has been simplified as they only need to implement the Iterable interface now, not the full Chunk interface.
---------
Signed-off-by: Fiona Liao <fiona.y.liao@gmail.com>
Co-authored-by: George Krajcsovits <krajorama@users.noreply.github.com>
* Fix issue where `chainSampleIterator` can obscure errors
Signed-off-by: Charles Korn <charles.korn@grafana.com>
* Address PR feedback.
Signed-off-by: Charles Korn <charles.korn@grafana.com>
---------
Signed-off-by: Charles Korn <charles.korn@grafana.com>
Instead of setting to nil and allocating a new slice every time the
merge is advanced, re-use the previous slice.
This is safe because the `currentSets` member is only used inside member
functions, and explicitly copied in `At()`, the only place it leaves the
struct.
Signed-off-by: Bryan Boreham <bjboreham@gmail.com>
Return annotations (warnings and infos) from PromQL queries
This generalizes the warnings we have already used before (but only for problems with remote read) as "annotations".
Annotations can be warnings or infos (the latter could be false positives). We do not treat them different in the API for now and return them all as "warnings". It would be easy to distinguish them and return infos separately, should that appear useful in the future.
The new annotations are then used to create a lot of warnings or infos during PromQL evaluations. Partially these are things we have wanted for a long time (e.g. inform the user that they have applied `rate` to a metric that doesn't look like a counter), but the new native histograms have created even more needs for those annotations (e.g. if a query tries to aggregate float numbers with histograms).
The annotations added here are not yet complete. A prominent example would be a warning about a range too short for a rate calculation. But such a warnings is more tricky to create with good fidelity and we will tackle it later.
Another TODO is to take annotations into account when evaluating recording rules.
---------
Signed-off-by: Jeanette Tan <jeanette.tan@grafana.com>
Wiser coders than myself have come to the conclusion that a `switch`
statement is almost always superior to a statement that includes any
`else if`.
The exceptions that I have found in our codebase are just these two:
* The `if else` is followed by an additional statement before the next
condition (separated by a `;`).
* The whole thing is within a `for` loop and `break` statements are
used. In this case, using `switch` would require tagging the `for`
loop, which probably tips the balance.
Why are `switch` statements more readable?
For one, fewer curly braces. But more importantly, the conditions all
have the same alignment, so the whole thing follows the natural flow
of going down a list of conditions. With `else if`, in contrast, all
conditions but the first are "hidden" behind `} else if `, harder to
spot and (for no good reason) presented differently from the first
condition.
I'm sure the aforemention wise coders can list even more reasons.
In any case, I like it so much that I have found myself recommending
it in code reviews. I would like to make it a habit in our code base,
without making it a hard requirement that we would test on the CI. But
for that, there has to be a role model, so this commit eliminates all
`if else` occurrences, unless it is autogenerated code or fits one of
the exceptions above.
Signed-off-by: beorn7 <beorn@grafana.com>
We haven't updated golint-ci in our CI yet, but this commit prepares
for that.
There are a lot of new warnings, and it is mostly because the "revive"
linter got updated. I agree with most of the new warnings, mostly
around not naming unused function parameters (although it is justified
in some cases for documentation purposes – while things like mocks are
a good example where not naming the parameter is clearer).
I'm pretty upset about the "empty block" warning to include `for`
loops. It's such a common pattern to do something in the head of the
`for` loop and then have an empty block. There is still an open issue
about this: https://github.com/mgechev/revive/issues/810 I have
disabled "revive" altogether in files where empty blocks are used
excessively, and I have made the effort to add individual
`// nolint:revive` where empty blocks are used just once or twice.
It's borderline noisy, though, but let's go with it for now.
I should mention that none of the "empty block" warnings for `for`
loop bodies were legitimate.
Signed-off-by: beorn7 <beorn@grafana.com>
This is a bit more conservative than we could be. As long as a chunk
isn't the first in a block, we can be pretty sure that the previous
chunk won't disappear. However, the incremental gain of returning
NotCounterReset in these cases is probably very small and might not be
worth the code complications.
Wwith this, we now also pay attention to an explicitly set counter
reset during ingestion. While the case doesn't show up in practice
yet, there could be scenarios where the metric source knows there was
a counter reset even if it might not be visible from the values in the
histogram. It is also useful for testing.
Signed-off-by: beorn7 <beorn@grafana.com>
Re-use previous memory if it is already of the correct type.
In `NewListSeries` we hoist the conversion to an interface value out
so it only allocates once.
Signed-off-by: Bryan Boreham <bjboreham@gmail.com>
Patterned after `Chunk.Iterator()`: pass the old iterator in so it
can be re-used to avoid allocating a new object.
(This commit does not do any re-use; it is just changing all the method
signatures so re-use is possible in later commits.)
Signed-off-by: Bryan Boreham <bjboreham@gmail.com>
Use new experimental package `golang.org/x/exp/slices`.
slices.Sort works on values that are directly comparable, like ints,
so avoids the overhad of an interface call to `.Less()`.
Left tests unchanged, because they don't need the speed and it may be
a cross-check that slices.Sort gives the same answer.
Signed-off-by: Bryan Boreham <bjboreham@gmail.com>
* Introduce out-of-order TSDB support
This implementation is based on this design doc:
https://docs.google.com/document/d/1Kppm7qL9C-BJB1j6yb6-9ObG3AbdZnFUBYPNNWwDBYM/edit?usp=sharing
This commit adds support to accept out-of-order ("OOO") sample into the TSDB
up to a configurable time allowance. If OOO is enabled, overlapping querying
are automatically enabled.
Most of the additions have been borrowed from
https://github.com/grafana/mimir-prometheus/
Here is the list ist of the original commits cherry picked
from mimir-prometheus into this branch:
- 4b2198d7ec
- 2836e5513f
- 00b379c3a5
- ff0dc75758
- a632c73352
- c6f3d4ab33
- 5e8406a1d4
- abde1e0ba1
- e70e769889
- df59320886
Co-authored-by: Jesus Vazquez <jesus.vazquez@grafana.com>
Co-authored-by: Ganesh Vernekar <ganeshvern@gmail.com>
Co-authored-by: Dieter Plaetinck <dieter@grafana.com>
Signed-off-by: Jesus Vazquez <jesus.vazquez@grafana.com>
* gofumpt files
Signed-off-by: Jesus Vazquez <jesus.vazquez@grafana.com>
* Add license header to missing files
Signed-off-by: Jesus Vazquez <jesus.vazquez@grafana.com>
* Fix OOO tests due to existing chunk disk mapper implementation
Signed-off-by: Jesus Vazquez <jesus.vazquez@grafana.com>
* Fix truncate int overflow
Signed-off-by: Jesus Vazquez <jesus.vazquez@grafana.com>
* Add Sync method to the WAL and update tests
Signed-off-by: Jesus Vazquez <jesus.vazquez@grafana.com>
* remove useless sync
Signed-off-by: Jesus Vazquez <jesus.vazquez@grafana.com>
* Update minOOOTime after truncating Head
* Update minOOOTime after truncating Head
Signed-off-by: Ganesh Vernekar <ganeshvern@gmail.com>
* Fix lint
Signed-off-by: Ganesh Vernekar <ganeshvern@gmail.com>
* Add a unit test
Signed-off-by: Ganesh Vernekar <ganeshvern@gmail.com>
Signed-off-by: Jesus Vazquez <jesus.vazquez@grafana.com>
* Load OutOfOrderTimeWindow only once per appender
Signed-off-by: Jesus Vazquez <jesus.vazquez@grafana.com>
* Fix OOO Head LabelValues and PostingsForMatchers
Signed-off-by: Jesus Vazquez <jesus.vazquez@grafana.com>
* Fix replay of OOO mmap chunks
Signed-off-by: Ganesh Vernekar <ganeshvern@gmail.com>
* Remove unnecessary err check
Signed-off-by: Jesus Vazquez <jesus.vazquez@grafana.com>
* Prevent panic with ApplyConfig
Signed-off-by: Ganesh Vernekar 15064823+codesome@users.noreply.github.com
Signed-off-by: Jesus Vazquez <jesus.vazquez@grafana.com>
* Run OOO compaction after restart if there is OOO data from WBL
Signed-off-by: Ganesh Vernekar 15064823+codesome@users.noreply.github.com
Signed-off-by: Jesus Vazquez <jesus.vazquez@grafana.com>
* Apply Bartek's suggestions
Co-authored-by: Bartlomiej Plotka <bwplotka@gmail.com>
Signed-off-by: Jesus Vazquez <jesus.vazquez@grafana.com>
* Refactor OOO compaction
Signed-off-by: Ganesh Vernekar <ganeshvern@gmail.com>
* Address comments and TODOs
- Added a comment explaining why we need the allow overlapping
compaction toggle
- Clarified TSDBConfig OutOfOrderTimeWindow doc
- Added an owner to all the TODOs in the code
Signed-off-by: Jesus Vazquez <jesus.vazquez@grafana.com>
* Run go format
Signed-off-by: Jesus Vazquez <jesus.vazquez@grafana.com>
* Fix remaining review comments
Signed-off-by: Ganesh Vernekar <ganeshvern@gmail.com>
* Fix tests
Signed-off-by: Ganesh Vernekar <ganeshvern@gmail.com>
* Change wbl reference when truncating ooo in TestHeadMinOOOTimeUpdate
Signed-off-by: Jesus Vazquez <jesus.vazquez@grafana.com>
* Fix TestWBLAndMmapReplay test failure on windows
Signed-off-by: Ganesh Vernekar <ganeshvern@gmail.com>
* Address most of the feedback
Signed-off-by: Ganesh Vernekar <ganeshvern@gmail.com>
* Refactor the block meta for out of order
Signed-off-by: Ganesh Vernekar <ganeshvern@gmail.com>
* Fix windows error
Signed-off-by: Ganesh Vernekar <ganeshvern@gmail.com>
* Fix review comments
Signed-off-by: Ganesh Vernekar <ganeshvern@gmail.com>
Signed-off-by: Jesus Vazquez <jesus.vazquez@grafana.com>
Signed-off-by: Ganesh Vernekar <ganeshvern@gmail.com>
Signed-off-by: Ganesh Vernekar 15064823+codesome@users.noreply.github.com
Co-authored-by: Ganesh Vernekar <15064823+codesome@users.noreply.github.com>
Co-authored-by: Ganesh Vernekar <ganeshvern@gmail.com>
Co-authored-by: Dieter Plaetinck <dieter@grafana.com>
Co-authored-by: Oleg Zaytsev <mail@olegzaytsev.com>
Co-authored-by: Bartlomiej Plotka <bwplotka@gmail.com>
There was a subtle and nasty bug in listSeriesIterator.Seek.
In addition, the Seek call is defined to be a no-op if the current
position of the iterator is already pointing to a suitable
sample. This commit adds fast paths for this case to several
potentially expensive Seek calls.
Another bug was in concreteSeriesIterator.Seek. It always searched the
whole series and not from the current position of the iterator.
Signed-off-by: beorn7 <beorn@grafana.com>
- Pick At... method via return value of Next/Seek.
- Do not clobber returned buckets.
- Add partial FloatHistogram suppert.
Note that the promql package is now _only_ dealing with
FloatHistograms, following the idea that PromQL only knows float
values.
As a byproduct, I have removed the histogramSeries metric. In my
understanding, series can have both float and histogram samples, so
that metric doesn't make sense anymore.
As another byproduct, I have converged the sampleBuf and the
histogramSampleBuf in memSeries into one. The sample type stored in
the sampleBuf has been extended to also contain histograms even before
this commit.
Signed-off-by: beorn7 <beorn@grafana.com>
This is to avoid copying the many fields of a histogram.Histogram all
the time.
This also fixes a bunch of formerly broken tests.
Signed-off-by: beorn7 <beorn@grafana.com>
This creates a new `model` directory and moves all data-model related
packages over there:
exemplar labels relabel rulefmt textparse timestamp value
All the others are more or less utilities and have been moved to `util`:
gate logging modetimevfs pool runtime
Signed-off-by: beorn7 <beorn@grafana.com>
* expose NewChainSampleIterator func
Signed-off-by: Ben Ye <ben.ye@bytedance.com>
* add comment
Signed-off-by: Ben Ye <ben.ye@bytedance.com>
* update comments
Signed-off-by: Ben Ye <ben.ye@bytedance.com>
A lot of this code was hacked together, literally during a
hackathon. This commit intends not to change the code substantially,
but just make the code obey the usual style practices.
A (possibly incomplete) list of areas:
* Generally address linter warnings.
* The `pgk` directory is deprecated as per dev-summit. No new packages should
be added to it. I moved the new `pkg/histogram` package to `model`
anticipating what's proposed in #9478.
* Make the naming of the Sparse Histogram more consistent. Including
abbreviations, there were just too many names for it: SparseHistogram,
Histogram, Histo, hist, his, shs, h. The idea is to call it "Histogram" in
general. Only add "Sparse" if it is needed to avoid confusion with
conventional Histograms (which is rare because the TSDB really has no notion
of conventional Histograms). Use abbreviations only in local scope, and then
really abbreviate (not just removing three out of seven letters like in
"Histo"). This is in the spirit of
https://github.com/golang/go/wiki/CodeReviewComments#variable-names
* Several other minor name changes.
* A lot of formatting of doc comments. For one, following
https://github.com/golang/go/wiki/CodeReviewComments#comment-sentences
, but also layout question, anticipating how things will look like
when rendered by `godoc` (even where `godoc` doesn't render them
right now because they are for unexported types or not a doc comment
at all but just a normal code comment - consistency is queen!).
* Re-enabled `TestQueryLog` and `TestEndopints` (they pass now,
leaving them disabled was presumably an oversight).
* Bucket iterator for histogram.Histogram is now created with a
method.
* HistogramChunk.iterator now allows iterator recycling. (I think
@dieterbe only commented it out because he was confused by the
question in the comment.)
* HistogramAppender.Append panics now because we decided to treat
staleness marker differently.
Signed-off-by: beorn7 <beorn@grafana.com>
* Push the matchers for LabelNames all the way into the index.
NB This doesn't actually implement it in the index, just plumbs it through for now...
Signed-off-by: Tom Wilkie <tom@grafana.com>
* Hack it up. Does not work.
Signed-off-by: Tom Wilkie <tom@grafana.com>
* Revert changes I don't understand
Can't see why do we need to hold a mutex on symbols, and the purpose of
the LabelNamesFor method.
Maybe I'll need to re-add this later.
Signed-off-by: Oleg Zaytsev <mail@olegzaytsev.com>
* Implement LabelNamesFor
This method provides the label names that appear in the postings
provided. We do that deeper than the label values because we know
beforehand that most of the label names we'll be the same across
different postings, and we don't want to go down an up looking up the
same symbols for all different series.
Signed-off-by: Oleg Zaytsev <mail@olegzaytsev.com>
* Mutex on symbols should be unlocked
However, I still don't understand why do we need a mutex here.
Signed-off-by: Oleg Zaytsev <mail@olegzaytsev.com>
* Fix head.LabelNamesFor
Signed-off-by: Oleg Zaytsev <mail@olegzaytsev.com>
* Implement mockIndex LabelNames with matchers
Signed-off-by: Oleg Zaytsev <mail@olegzaytsev.com>
* Nitpick on slice initialisation
Signed-off-by: Oleg Zaytsev <mail@olegzaytsev.com>
* Add tests for LabelNamesWithMatchers
Signed-off-by: Oleg Zaytsev <mail@olegzaytsev.com>
* Fix the mutex mess on head.LabelValues/LabelNames
I still don't see why we need to grab that unrelated mutex, but at least
now we're grabbing it consistently
Signed-off-by: Oleg Zaytsev <mail@olegzaytsev.com>
* Check error after iterating postings
Signed-off-by: Oleg Zaytsev <mail@olegzaytsev.com>
* Use the error from posting when there was en error in postings
Co-authored-by: Ganesh Vernekar <15064823+codesome@users.noreply.github.com>
Signed-off-by: Oleg Zaytsev <mail@olegzaytsev.com>
* Update storage/interface.go comment
Signed-off-by: Oleg Zaytsev <mail@olegzaytsev.com>
Co-authored-by: Ganesh Vernekar <15064823+codesome@users.noreply.github.com>
* Update tsdb/index/index.go comment
Signed-off-by: Oleg Zaytsev <mail@olegzaytsev.com>
Co-authored-by: Ganesh Vernekar <15064823+codesome@users.noreply.github.com>
* Update tsdb/index/index.go wrapped error msg
Signed-off-by: Oleg Zaytsev <mail@olegzaytsev.com>
Co-authored-by: Ganesh Vernekar <15064823+codesome@users.noreply.github.com>
* Update tsdb/index/index.go wrapped error msg
Signed-off-by: Oleg Zaytsev <mail@olegzaytsev.com>
Co-authored-by: Ganesh Vernekar <15064823+codesome@users.noreply.github.com>
* Update tsdb/index/index.go warpped error msg
Signed-off-by: Oleg Zaytsev <mail@olegzaytsev.com>
Co-authored-by: Ganesh Vernekar <15064823+codesome@users.noreply.github.com>
* Remove unneeded comment
Signed-off-by: Oleg Zaytsev <mail@olegzaytsev.com>
* Add testcases for LabelNames w/matchers in api.go
Signed-off-by: Oleg Zaytsev <mail@olegzaytsev.com>
* Use t.Cleanup() instead of defer in tests
Signed-off-by: Oleg Zaytsev <mail@olegzaytsev.com>
Co-authored-by: Tom Wilkie <tom@grafana.com>
Co-authored-by: Ganesh Vernekar <15064823+codesome@users.noreply.github.com>
* Append sparse histograms into the Head block
Signed-off-by: Ganesh Vernekar <ganeshvern@gmail.com>
* Add AtHistogram() to Iterator interface. Make HistoChunk conform to Chunk interface.
Signed-off-by: Ganesh Vernekar <ganeshvern@gmail.com>
* MultiError: Refactored MultiError for more concise and safe usage.
* Less lines
* Goland IDE was marking every usage of old MultiError "potential nil" error
* It was easy to forgot using Err() when error was returned, now it's safely assured on compile time.
NOTE: Potentially I would rename package to merrors. (: In different PR.
Signed-off-by: Bartlomiej Plotka <bwplotka@gmail.com>
* Addressed review comments.
Signed-off-by: Bartlomiej Plotka <bwplotka@gmail.com>
* Addressed comments.
Signed-off-by: Bartlomiej Plotka <bwplotka@gmail.com>
* Fix after rebase.
Signed-off-by: Bartlomiej Plotka <bwplotka@gmail.com>
