prometheus/util/stats/query_stats.go
zhulongcheng 970ef41bb6 Fix exported function comments (#6002)
Signed-off-by: zhulongcheng <zhulongcheng.dev@gmail.com>
2019-09-10 14:45:09 +01:00

158 lines
4 KiB
Go

// Copyright 2013 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 stats
import (
"context"
opentracing "github.com/opentracing/opentracing-go"
"github.com/prometheus/client_golang/prometheus"
)
// QueryTiming identifies the code area or functionality in which time is spent
// during a query.
type QueryTiming int
// Query timings.
const (
EvalTotalTime QueryTiming = iota
ResultSortTime
QueryPreparationTime
InnerEvalTime
ExecQueueTime
ExecTotalTime
)
// Return a string representation of a QueryTiming identifier.
func (s QueryTiming) String() string {
switch s {
case EvalTotalTime:
return "Eval total time"
case ResultSortTime:
return "Result sorting time"
case QueryPreparationTime:
return "Query preparation time"
case InnerEvalTime:
return "Inner eval time"
case ExecQueueTime:
return "Exec queue wait time"
case ExecTotalTime:
return "Exec total time"
default:
return "Unknown query timing"
}
}
// SpanOperation returns a string representation of a QueryTiming span operation.
func (s QueryTiming) SpanOperation() string {
switch s {
case EvalTotalTime:
return "promqlEval"
case ResultSortTime:
return "promqlSort"
case QueryPreparationTime:
return "promqlPrepare"
case InnerEvalTime:
return "promqlInnerEval"
case ExecQueueTime:
return "promqlExecQueue"
case ExecTotalTime:
return "promqlExec"
default:
return "Unknown query timing"
}
}
// queryTimings with all query timers mapped to durations.
type queryTimings struct {
EvalTotalTime float64 `json:"evalTotalTime"`
ResultSortTime float64 `json:"resultSortTime"`
QueryPreparationTime float64 `json:"queryPreparationTime"`
InnerEvalTime float64 `json:"innerEvalTime"`
ExecQueueTime float64 `json:"execQueueTime"`
ExecTotalTime float64 `json:"execTotalTime"`
}
// QueryStats currently only holding query timings.
type QueryStats struct {
Timings queryTimings `json:"timings,omitempty"`
}
// NewQueryStats makes a QueryStats struct with all QueryTimings found in the
// given TimerGroup.
func NewQueryStats(tg *QueryTimers) *QueryStats {
var qt queryTimings
for s, timer := range tg.TimerGroup.timers {
switch s {
case EvalTotalTime:
qt.EvalTotalTime = timer.Duration()
case ResultSortTime:
qt.ResultSortTime = timer.Duration()
case QueryPreparationTime:
qt.QueryPreparationTime = timer.Duration()
case InnerEvalTime:
qt.InnerEvalTime = timer.Duration()
case ExecQueueTime:
qt.ExecQueueTime = timer.Duration()
case ExecTotalTime:
qt.ExecTotalTime = timer.Duration()
}
}
qs := QueryStats{Timings: qt}
return &qs
}
// SpanTimer unifies tracing and timing, to reduce repetition.
type SpanTimer struct {
timer *Timer
observers []prometheus.Observer
span opentracing.Span
}
func NewSpanTimer(ctx context.Context, operation string, timer *Timer, observers ...prometheus.Observer) (*SpanTimer, context.Context) {
span, ctx := opentracing.StartSpanFromContext(ctx, operation)
timer.Start()
return &SpanTimer{
timer: timer,
observers: observers,
span: span,
}, ctx
}
func (s *SpanTimer) Finish() {
s.timer.Stop()
s.span.Finish()
for _, obs := range s.observers {
obs.Observe(s.timer.ElapsedTime().Seconds())
}
}
type QueryTimers struct {
*TimerGroup
}
func NewQueryTimers() *QueryTimers {
return &QueryTimers{NewTimerGroup()}
}
func (qs *QueryTimers) GetSpanTimer(ctx context.Context, qt QueryTiming, observers ...prometheus.Observer) (*SpanTimer, context.Context) {
return NewSpanTimer(ctx, qt.SpanOperation(), qs.TimerGroup.GetTimer(qt), observers...)
}