prometheus/storage/metric/view.go

163 lines
5.4 KiB
Go

// Copyright 2013 Prometheus Team
// 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 metric
import (
"sort"
"time"
clientmodel "github.com/prometheus/client_golang/model"
)
var (
// firstSupertime is the smallest valid supertime that may be seeked to.
firstSupertime = []byte{0, 0, 0, 0, 0, 0, 0, 0}
// lastSupertime is the largest valid supertime that may be seeked to.
lastSupertime = []byte{127, 255, 255, 255, 255, 255, 255, 255}
)
// ViewRequestBuilder represents the summation of all datastore queries that
// shall be performed to extract values. Each operation mutates the state of
// the builder.
type ViewRequestBuilder interface {
GetMetricAtTime(fingerprint *clientmodel.Fingerprint, time clientmodel.Timestamp)
GetMetricAtInterval(fingerprint *clientmodel.Fingerprint, from, through clientmodel.Timestamp, interval time.Duration)
GetMetricRange(fingerprint *clientmodel.Fingerprint, from, through clientmodel.Timestamp)
ScanJobs() scanJobs
}
// viewRequestBuilder contains the various unoptimized requests for data.
type viewRequestBuilder struct {
operations map[clientmodel.Fingerprint]ops
}
// NewViewRequestBuilder furnishes a ViewRequestBuilder for remarking what types
// of queries to perform.
func NewViewRequestBuilder() *viewRequestBuilder {
return &viewRequestBuilder{
operations: make(map[clientmodel.Fingerprint]ops),
}
}
var getValuesAtTimes = newValueAtTimeList(10 * 1024)
// GetMetricAtTime gets for the given Fingerprint either the value at that time
// if there is an match or the one or two values adjacent thereto.
func (v *viewRequestBuilder) GetMetricAtTime(fingerprint *clientmodel.Fingerprint, time clientmodel.Timestamp) {
ops := v.operations[*fingerprint]
op, _ := getValuesAtTimes.Get()
op.time = time
ops = append(ops, op)
v.operations[*fingerprint] = ops
}
var getValuesAtIntervals = newValueAtIntervalList(10 * 1024)
// GetMetricAtInterval gets for the given Fingerprint either the value at that
// interval from From through Through if there is an match or the one or two
// values adjacent for each point.
func (v *viewRequestBuilder) GetMetricAtInterval(fingerprint *clientmodel.Fingerprint, from, through clientmodel.Timestamp, interval time.Duration) {
ops := v.operations[*fingerprint]
op, _ := getValuesAtIntervals.Get()
op.from = from
op.through = through
op.interval = interval
ops = append(ops, op)
v.operations[*fingerprint] = ops
}
var getValuesAlongRanges = newValueAlongRangeList(10 * 1024)
// GetMetricRange gets for the given Fingerprint the values that occur
// inclusively from From through Through.
func (v *viewRequestBuilder) GetMetricRange(fingerprint *clientmodel.Fingerprint, from, through clientmodel.Timestamp) {
ops := v.operations[*fingerprint]
op, _ := getValuesAlongRanges.Get()
op.from = from
op.through = through
ops = append(ops, op)
v.operations[*fingerprint] = ops
}
var getValuesAtIntervalAlongRanges = newValueAtIntervalAlongRangeList(10 * 1024)
// GetMetricRangeAtInterval gets value ranges at intervals for the given
// Fingerprint:
//
// |----| |----| |----| |----|
// ^ ^ ^ ^ ^ ^
// | \------------/ \----/ |
// from interval rangeDuration through
func (v *viewRequestBuilder) GetMetricRangeAtInterval(fingerprint *clientmodel.Fingerprint, from, through clientmodel.Timestamp, interval, rangeDuration time.Duration) {
ops := v.operations[*fingerprint]
op, _ := getValuesAtIntervalAlongRanges.Get()
op.rangeFrom = from
op.rangeThrough = from.Add(rangeDuration)
op.rangeDuration = rangeDuration
op.interval = interval
op.through = through
ops = append(ops, op)
v.operations[*fingerprint] = ops
}
// ScanJobs emits the optimized scans that will occur in the data store. This
// effectively resets the ViewRequestBuilder back to a pristine state.
func (v *viewRequestBuilder) ScanJobs() (j scanJobs) {
for fingerprint, operations := range v.operations {
sort.Sort(startsAtSort{operations})
fpCopy := fingerprint
j = append(j, scanJob{
fingerprint: &fpCopy,
// BUG: Evaluate whether we need to implement an optimize() working also
// for getValueRangeAtIntervalOp and use it here instead of just passing
// through the list of ops as-is.
operations: operations,
})
delete(v.operations, fingerprint)
}
sort.Sort(j)
return
}
type view struct {
*memorySeriesStorage
}
func (v view) appendSamples(fingerprint *clientmodel.Fingerprint, samples Values) {
v.memorySeriesStorage.appendSamplesWithoutIndexing(fingerprint, samples)
}
func newView() view {
return view{NewMemorySeriesStorage(MemorySeriesOptions{})}
}
func giveBackOp(op interface{}) bool {
switch v := op.(type) {
case *getValuesAtTimeOp:
return getValuesAtTimes.Give(v)
case *getValuesAtIntervalOp:
return getValuesAtIntervals.Give(v)
case *getValuesAlongRangeOp:
return getValuesAlongRanges.Give(v)
case *getValueRangeAtIntervalOp:
return getValuesAtIntervalAlongRanges.Give(v)
default:
panic("unrecognized operation")
}
}