telegraf/internal/models/running_output.go

203 lines
5.0 KiB
Go

package models
import (
"log"
"sync"
"time"
"github.com/influxdata/telegraf"
"github.com/influxdata/telegraf/internal/buffer"
"github.com/influxdata/telegraf/selfstat"
)
const (
// Default size of metrics batch size.
DEFAULT_METRIC_BATCH_SIZE = 1000
// Default number of metrics kept. It should be a multiple of batch size.
DEFAULT_METRIC_BUFFER_LIMIT = 10000
)
// RunningOutput contains the output configuration
type RunningOutput struct {
Name string
Output telegraf.Output
Config *OutputConfig
MetricBufferLimit int
MetricBatchSize int
MetricsFiltered selfstat.Stat
MetricsWritten selfstat.Stat
BufferSize selfstat.Stat
BufferLimit selfstat.Stat
WriteTime selfstat.Stat
metrics *buffer.Buffer
failMetrics *buffer.Buffer
// Guards against concurrent calls to Add, Push, Reset
aggMutex sync.Mutex
// Guards against concurrent calls to the Output as described in #3009
writeMutex sync.Mutex
}
// OutputConfig containing name and filter
type OutputConfig struct {
Name string
Filter Filter
}
func NewRunningOutput(
name string,
output telegraf.Output,
conf *OutputConfig,
batchSize int,
bufferLimit int,
) *RunningOutput {
if bufferLimit == 0 {
bufferLimit = DEFAULT_METRIC_BUFFER_LIMIT
}
if batchSize == 0 {
batchSize = DEFAULT_METRIC_BATCH_SIZE
}
ro := &RunningOutput{
Name: name,
metrics: buffer.NewBuffer(batchSize),
failMetrics: buffer.NewBuffer(bufferLimit),
Output: output,
Config: conf,
MetricBufferLimit: bufferLimit,
MetricBatchSize: batchSize,
MetricsWritten: selfstat.Register(
"write",
"metrics_written",
map[string]string{"output": name},
),
MetricsFiltered: selfstat.Register(
"write",
"metrics_filtered",
map[string]string{"output": name},
),
BufferSize: selfstat.Register(
"write",
"buffer_size",
map[string]string{"output": name},
),
BufferLimit: selfstat.Register(
"write",
"buffer_limit",
map[string]string{"output": name},
),
WriteTime: selfstat.RegisterTiming(
"write",
"write_time_ns",
map[string]string{"output": name},
),
}
ro.BufferLimit.Set(int64(ro.MetricBufferLimit))
return ro
}
// AddMetric adds a metric to the output. This function can also write cached
// points if FlushBufferWhenFull is true.
func (ro *RunningOutput) AddMetric(metric telegraf.Metric) {
if ok := ro.Config.Filter.Select(metric); !ok {
ro.MetricsFiltered.Incr(1)
return
}
ro.Config.Filter.Modify(metric)
if len(metric.FieldList()) == 0 {
return
}
if output, ok := ro.Output.(telegraf.AggregatingOutput); ok {
ro.aggMutex.Lock()
output.Add(metric)
ro.aggMutex.Unlock()
return
}
ro.metrics.Add(metric)
if ro.metrics.Len() == ro.MetricBatchSize {
batch := ro.metrics.Batch(ro.MetricBatchSize)
err := ro.write(batch)
if err != nil {
ro.failMetrics.Add(batch...)
log.Printf("E! Error writing to output [%s]: %v", ro.Name, err)
}
}
}
// Write writes all cached points to this output.
func (ro *RunningOutput) Write() error {
if output, ok := ro.Output.(telegraf.AggregatingOutput); ok {
ro.aggMutex.Lock()
metrics := output.Push()
ro.metrics.Add(metrics...)
output.Reset()
ro.aggMutex.Unlock()
}
nFails, nMetrics := ro.failMetrics.Len(), ro.metrics.Len()
ro.BufferSize.Set(int64(nFails + nMetrics))
log.Printf("D! Output [%s] buffer fullness: %d / %d metrics. ",
ro.Name, nFails+nMetrics, ro.MetricBufferLimit)
var err error
if !ro.failMetrics.IsEmpty() {
// how many batches of failed writes we need to write.
nBatches := nFails/ro.MetricBatchSize + 1
batchSize := ro.MetricBatchSize
for i := 0; i < nBatches; i++ {
// If it's the last batch, only grab the metrics that have not had
// a write attempt already (this is primarily to preserve order).
if i == nBatches-1 {
batchSize = nFails % ro.MetricBatchSize
}
batch := ro.failMetrics.Batch(batchSize)
// If we've already failed previous writes, don't bother trying to
// write to this output again. We are not exiting the loop just so
// that we can rotate the metrics to preserve order.
if err == nil {
err = ro.write(batch)
}
if err != nil {
ro.failMetrics.Add(batch...)
}
}
}
batch := ro.metrics.Batch(ro.MetricBatchSize)
// see comment above about not trying to write to an already failed output.
// if ro.failMetrics is empty then err will always be nil at this point.
if err == nil {
err = ro.write(batch)
}
if err != nil {
ro.failMetrics.Add(batch...)
return err
}
return nil
}
func (ro *RunningOutput) write(metrics []telegraf.Metric) error {
nMetrics := len(metrics)
if nMetrics == 0 {
return nil
}
ro.writeMutex.Lock()
defer ro.writeMutex.Unlock()
start := time.Now()
err := ro.Output.Write(metrics)
elapsed := time.Since(start)
if err == nil {
log.Printf("D! Output [%s] wrote batch of %d metrics in %s\n",
ro.Name, nMetrics, elapsed)
ro.MetricsWritten.Incr(int64(nMetrics))
ro.WriteTime.Incr(elapsed.Nanoseconds())
}
return err
}