Commit graph

13 commits

Author SHA1 Message Date
Julius Volz 3bfec97d46 Make the storage interface higher-level.
See discussion in
https://groups.google.com/forum/#!topic/prometheus-developers/bkuGbVlvQ9g

The main idea is that the user of a storage shouldn't have to deal with
fingerprints anymore, and should not need to do an individual preload
call for each metric. The storage interface needs to be made more
high-level to not expose these details.

This also makes it easier to reuse the same storage interface for remote
storages later, as fewer roundtrips are required and the fingerprint
concept doesn't work well across the network.

NOTE: this deliberately gets rid of a small optimization in the old
query Analyzer, where we dedupe instants and ranges for the same series.
This should have a minor impact, as most queries do not have multiple
selectors loading the same series (and at the same offset).
2016-07-25 13:59:22 +02:00
beorn7 836f1db04c Improve MetricsForLabelMatchers
WIP: This needs more tests.

It now gets a from and through value, which it may opportunistically
use to optimize the retrieval. With possible future range indices,
this could be used in a very efficient way. This change merely applies
some easy checks, which should nevertheless solve the use case of
heavy rule evaluations on servers with a lot of series churn.

Idea is the following:

- Only archive series that are at least as old as the headChunkTimeout
  (which was already extremely unlikely to happen).

- Then maintain a high watermark for the last archival, i.e. no
  archived series has a sample more recent than that watermark.

- Any query that doesn't reach to a time before that watermark doesn't
  have to touch the archive index at all. (A production server at
  Soundcloud with the aforementioned series churn and heavy rule
  evaluations spends 50% of its CPU time in archive index
  lookups. Since rule evaluations usually only touch very recent
  values, most of those lookup should disappear with this change.)

- Federation with a very broad label matcher will profit from this,
  too.

As a byproduct, the un-needed MetricForFingerprint method was removed
from the Storage interface.
2016-03-09 00:25:59 +01:00
beorn7 1e13f89039 Return SamplePair istead of *SamplePair consistently
Formalize ZeroSamplePair as return value for non-existing samples.

Change LastSamplePairForFingerprint to return a SamplePair (and not a
pointer to it), which saves allocations in a potentially extremely
frequent call.
2016-02-19 17:00:40 +01:00
Fabian Reinartz b35e25a082 Don't federate stale samples 2015-12-16 13:45:44 +01:00
Julius Volz dac26cef71 Rename global "labels" config option to "external_labels". 2015-09-29 20:54:20 +02:00
beorn7 ca63c05b4e Fix creation of protobuf fields 2015-09-18 19:00:53 +02:00
Fabian Reinartz 9bbd9264e2 Add global labels to federation 2015-09-03 16:38:03 +02:00
Julius Volz 995d3b831d Fix most golint warnings.
This is with `golint -min_confidence=0.5`.

I left several lint warnings untouched because they were either
incorrect or I felt it was better not to change them at the moment.
2015-08-26 12:44:46 +02:00
Fabian Reinartz d6b8da8d43 Switch promql types to common/model 2015-08-25 13:49:14 +02:00
Fabian Reinartz d6d88f8950 Add missing license headers 2015-08-24 19:19:21 +02:00
Fabian Reinartz 47aa0d536c Use common/expfmt in federation 2015-08-21 13:33:38 +02:00
Fabian Reinartz 306e8468a0 Switch from client_golang/model to common/model 2015-08-21 13:33:38 +02:00
Fabian Reinartz 39a8254963 web: add basic federation support.
This commit adds a federation handler on /federate. It accepts `match[]`
query parameters containing vector selectors. Their intersection determines
the in-memory metrics that are returned in the same way as the
/metrics endpoint does (modulo sorting).
2015-06-23 13:45:15 +02:00