prometheus/storage/remote/storage.go
Thibault Chataigner bf4a279a91 Remote storage reads based on oldest timestamp in primary storage (#3129)
Currently all read queries are simply pushed to remote read clients.
This is fine, except for remote storage for wich it unefficient and
make query slower even if remote read is unnecessary.
So we need instead to compare the oldest timestamp in primary/local
storage with the query range lower boundary. If the oldest timestamp
is older than the mint parameter, then there is no need for remote read.
This is an optionnal behavior per remote read client.

Signed-off-by: Thibault Chataigner <t.chataigner@criteo.com>
2017-10-18 12:08:14 +01:00

125 lines
3 KiB
Go

// Copyright 2017 The Prometheus Authors
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
package remote
import (
"sync"
"github.com/go-kit/kit/log"
"github.com/prometheus/common/model"
"github.com/prometheus/prometheus/config"
)
// Callback func that return the oldest timestamp stored in a storage.
type startTimeCallback func() (int64, error)
// Storage represents all the remote read and write endpoints. It implements
// storage.Storage.
type Storage struct {
logger log.Logger
mtx sync.RWMutex
// For writes
queues []*QueueManager
// For reads
clients []*Client
localStartTimeCallback startTimeCallback
externalLabels model.LabelSet
}
// NewStorage returns a remote.Storage.
func NewStorage(l log.Logger, stCallback startTimeCallback) *Storage {
if l == nil {
l = log.NewNopLogger()
}
return &Storage{logger: l, localStartTimeCallback: stCallback}
}
// ApplyConfig updates the state as the new config requires.
func (s *Storage) ApplyConfig(conf *config.Config) error {
s.mtx.Lock()
defer s.mtx.Unlock()
// Update write queues
newQueues := []*QueueManager{}
// TODO: we should only stop & recreate queues which have changes,
// as this can be quite disruptive.
for i, rwConf := range conf.RemoteWriteConfigs {
c, err := NewClient(i, &clientConfig{
url: rwConf.URL,
timeout: rwConf.RemoteTimeout,
httpClientConfig: rwConf.HTTPClientConfig,
})
if err != nil {
return err
}
newQueues = append(newQueues, NewQueueManager(
s.logger,
defaultQueueManagerConfig,
conf.GlobalConfig.ExternalLabels,
rwConf.WriteRelabelConfigs,
c,
))
}
for _, q := range s.queues {
q.Stop()
}
s.queues = newQueues
for _, q := range s.queues {
q.Start()
}
// Update read clients
clients := []*Client{}
for i, rrConf := range conf.RemoteReadConfigs {
c, err := NewClient(i, &clientConfig{
url: rrConf.URL,
timeout: rrConf.RemoteTimeout,
httpClientConfig: rrConf.HTTPClientConfig,
readRecent: rrConf.ReadRecent,
})
if err != nil {
return err
}
clients = append(clients, c)
}
s.clients = clients
s.externalLabels = conf.GlobalConfig.ExternalLabels
return nil
}
// StartTime implements the Storage interface.
func (s *Storage) StartTime() (int64, error) {
return int64(model.Latest), nil
}
// Close the background processing of the storage queues.
func (s *Storage) Close() error {
s.mtx.Lock()
defer s.mtx.Unlock()
for _, q := range s.queues {
q.Stop()
}
return nil
}