* Document le and quantile label transition due to native histograms
Fixes: #12984
For full explanation see the related issue. The le and quantile labels
are formatted as float with trailing .0 for whole number values when
native histograms is enabled, e.g. 10.0. This changes the resulting series
in Prometheus if previously we scraped the whole number itself, e.g. 10
over the text format.
Signed-off-by: György Krajcsovits <gyorgy.krajcsovits@grafana.com>
---------
Signed-off-by: György Krajcsovits <gyorgy.krajcsovits@grafana.com>
Signed-off-by: George Krajcsovits <krajorama@users.noreply.github.com>
* A registerer is passed to the scrape Manager,
and all scrape metrics register with it.
* For now the registry which we pass to the scrape
Manager is still the global one.
Signed-off-by: Paulin Todev <paulin.todev@gmail.com>
* Added ability to specify scrape protocols to accept during HTTP content type negotiation.
This is done via new option in GlobalConfig and ScrapeConfig: "scrape_protocol"
Signed-off-by: bwplotka <bwplotka@gmail.com>
* Fixed readability and log message.
Signed-off-by: bwplotka <bwplotka@gmail.com>
---------
Signed-off-by: bwplotka <bwplotka@gmail.com>
We don't need the buffer to read the response until the scrape http call
returns; creating it earlier makes the buffer pool larger.
I split `scrape()` into `scrape()` which returns with the http response,
and `readResponse()` which decompresses and copies the data into the
supplied buffer. This design was chosen to minimize impact on the logic.
Signed-off-by: Bryan Boreham <bjboreham@gmail.com>
The parsing doesn't seem to be perfect as I don't get all classic buckets
possibly another bug found?
Signed-off-by: György Krajcsovits <gyorgy.krajcsovits@grafana.com>
It's possible (quite common on Kubernetes) to have a service discovery
return thousands of targets then drop most of them in relabel rules.
The main place this data is used is to display in the web UI, where
you don't want thousands of lines of display.
The new limit is `keep_dropped_targets`, which defaults to 0
for backwards-compatibility.
Signed-off-by: Bryan Boreham <bjboreham@gmail.com>
Continue to remove confusion that histogram samples are also samples
and histogram values are also values etc. by renaming float values and
float samples using the same schema as for histograms.
Concretely:
- result → resultFloats (corresponding to resultHistograms)
- pendingResult → pendingFloats (corresponding to pendingHistograms)
- rolledbackResult → rolledbackFloats (corresponding to rolledbackHistograms)
- sample → floatSample (corresponding to histogramSample)
This also order the fields in `collectResultAppender` more
consistently.
Signed-off-by: beorn7 <beorn@grafana.com>
This has become a requirement for native histograms, as a single
histogram sample commonly has many buckets, so that providing many
exemplars makes sense.
Since OM text doesn't support native histograms yet, the test had to
be expanded to also support protobuf test cases.
Signed-off-by: beorn7 <beorn@grafana.com>
So far, if a target exposes a histogram with both classic and native
buckets, a native-histogram enabled Prometheus would ignore the
classic buckets. With the new scrape config option
`scrape_classic_histograms` set, both buckets will be ingested,
creating all the series of a classic histogram in parallel to the
native histogram series. For example, a histogram `foo` would create a
native histogram series `foo` and classic series called `foo_sum`,
`foo_count`, and `foo_bucket`.
This feature can be used in a migration strategy from classic to
native histograms, where it is desired to have a transition period
during which both native and classic histograms are present.
Note that two bugs in classic histogram parsing were found and fixed
as a byproduct of testing the new feature:
1. Series created from classic _gauge_ histograms didn't get the
_sum/_count/_bucket prefix set.
2. Values of classic _float_ histograms weren't parsed properly.
Signed-off-by: beorn7 <beorn@grafana.com>
Consider code like:
for i := 0; i < numTargets; i++ {
stopFuncs = append(stopFuncs, func() {
time.Sleep(i*20*time.Millisecond)
})
}
Because the loop variable i is shared by all closures,
all the stopFuncs sleep for numTargets*20 ms.
If the i were made per-iteration, as we are considering
for a future Go release, the stopFuncs would have sleep
durations ranging from 0 to (numTargets-1)*20 ms.
Two tests had code like this and were checking that the
aggregate sleep was at least numTargets*20 ms
("at least as long as the last target slept"). This is only true
today because i == numTarget during all the sleeps.
To keep the code working even if the semantics of this loop
change, this PR computes
d := time.Duration((i+1)*20) * time.Millisecond
outside the closure (but inside the loop body), and then each
closure has its own d. Now the sleeps range from 20 ms
to numTargets*20 ms, keeping the test passing
(and probably behaving closer to the intent of the test author).
The failure being fixed can be reproduced by using the current
Go development branch with
GOEXPERIMENT=loopvar go test
Signed-off-by: Russ Cox <rsc@golang.org>
Refactors textparser test to use a common test utility to create
protobuf representation from MetricFamily
Signed-off-by: György Krajcsovits <gyorgy.krajcsovits@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>
The `yolostring` routine was intended to avoid an allocation when
converting from a `[]byte` to a `string` for map lookup.
However, since 2014 Go has recognized this pattern and does not make
a copy of the data when looking up a map. So the unsafe code is not
necessary.
In line with this, constants like `scrapeHealthMetricName` also become
`[]byte`.
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>
And a few cases of `EmptyLabels()`.
Replacing code which assumes the internal structure of `Labels`.
Signed-off-by: Bryan Boreham <bjboreham@gmail.com>
* Append metadata to the WAL
Signed-off-by: Paschalis Tsilias <paschalist0@gmail.com>
* Remove extra whitespace; Reword some docstrings and comments
Signed-off-by: Paschalis Tsilias <paschalist0@gmail.com>
* Use RLock() for hasNewMetadata check
Signed-off-by: Paschalis Tsilias <paschalist0@gmail.com>
* Use single byte for metric type in RefMetadata
Signed-off-by: Paschalis Tsilias <paschalist0@gmail.com>
* Update proposed WAL format for single-byte type metadata
Signed-off-by: Paschalis Tsilias <paschalist0@gmail.com>
* Address first round of review comments
Signed-off-by: Paschalis Tsilias <paschalist0@gmail.com>
* Amend description of metadata in wal.md
Signed-off-by: Paschalis Tsilias <paschalist0@gmail.com>
* Correct key used to retrieve metadata from cache
When we're setting metadata entries in the scrapeCace, we're using the
p.Help(), p.Unit(), p.Type() helpers, which retrieve the series name and
use it as the cache key. When checking for cache entries though, we used
p.Series() as the key, which included the metric name _with_ its labels.
That meant that we were never actually hitting the cache. We're fixing
this by utiling the __name__ internal label for correctly getting the
cache entries after they've been set by setHelp(), setType() or
setUnit().
Signed-off-by: Paschalis Tsilias <paschalist0@gmail.com>
* Put feature behind a feature flag
Signed-off-by: Paschalis Tsilias <paschalist0@gmail.com>
* Reorder WAL format document
Signed-off-by: Paschalis Tsilias <paschalist0@gmail.com>
* Fix CR comments
Signed-off-by: Paschalis Tsilias <paschalist0@gmail.com>
* Extract logic about changing metadata in an anonymous function
Signed-off-by: Paschalis Tsilias <paschalist0@gmail.com>
* Implement new proposed WAL format and amend relevant tests
Signed-off-by: Paschalis Tsilias <paschalist0@gmail.com>
* Use 'const' for metadata field names
Signed-off-by: Paschalis Tsilias <paschalist0@gmail.com>
* Apply metadata to head memSeries in Commit, not in AppendMetadata
Signed-off-by: Paschalis Tsilias <paschalist0@gmail.com>
* Add docstring and rename extracted helper in scrape.go
Signed-off-by: Paschalis Tsilias <paschalist0@gmail.com>
* Fix review comments around TestMetadata* tests
Signed-off-by: Paschalis Tsilias <paschalist0@gmail.com>
* Rebase with merged TSDB changes; fix duplicate definitions after rebase
Signed-off-by: Paschalis Tsilias <paschalist0@gmail.com>
* Remove leftover changes on db_test.go
Signed-off-by: Paschalis Tsilias <paschalist0@gmail.com>
* Rename feature flag
Signed-off-by: Paschalis Tsilias <paschalist0@gmail.com>
* Simplify updateMetadata helper function
Signed-off-by: Paschalis Tsilias <paschalist0@gmail.com>
* Remove extra newline
Signed-off-by: Paschalis Tsilias <paschalist0@gmail.com>
Signed-off-by: Paschalis Tsilias <paschalist0@gmail.com>
* Send target and metadata cache in context (again)
The previous attempt was rolled back in #10590 due to memory issues.
`sl.parentCtx` and `sl.ctx` both had a copy of the cache and target info
in the previous attempt and it was hard to pin-point where the context
was being retained causing the memory increase.
I've experimented a bunch in #10627 to figure out that this approach doesn't
cause memory increase. Beyond that, just using this info in _any_ other context
is causing a memory increase.
The change fixed a bunch of long-standing in the OTel Collector that the
community was waiting on and release is blocked on a few downstream distrubutions
of OTel Collector waiting on a fix. I propose to merge this change in while
I investigate what is happening.
Signed-off-by: Goutham Veeramachaneni <gouthamve@gmail.com>
* Gate the change behind a manager option
Signed-off-by: Goutham Veeramachaneni <gouthamve@gmail.com>
* refactor: move from io/ioutil to io and os packages
* use fs.DirEntry instead of os.FileInfo after os.ReadDir
Signed-off-by: MOREL Matthieu <matthieu.morel@cnp.fr>
* scrape: allow providing a custom Dialer for scraping
This commit extends config.ScrapeConfig with an optional field to
override how HTTP connections to targets are created. This field is not
set directly in Prometheus, and is only added for the convenience of
downstream importers.
Closes#9706
Signed-off-by: Robert Fratto <robertfratto@gmail.com>
* scrape: move custom dial function to scrape.Options
Signed-off-by: Robert Fratto <robertfratto@gmail.com>
