VictoriaMetrics/app/vmagent/remotewrite/pendingseries.go
2024-04-20 21:00:03 +02:00

311 lines
9.2 KiB
Go

package remotewrite
import (
"flag"
"sync"
"sync/atomic"
"time"
"github.com/VictoriaMetrics/VictoriaMetrics/lib/bytesutil"
"github.com/VictoriaMetrics/VictoriaMetrics/lib/cgroup"
"github.com/VictoriaMetrics/VictoriaMetrics/lib/decimal"
"github.com/VictoriaMetrics/VictoriaMetrics/lib/encoding/zstd"
"github.com/VictoriaMetrics/VictoriaMetrics/lib/fasttime"
"github.com/VictoriaMetrics/VictoriaMetrics/lib/flagutil"
"github.com/VictoriaMetrics/VictoriaMetrics/lib/logger"
"github.com/VictoriaMetrics/VictoriaMetrics/lib/persistentqueue"
"github.com/VictoriaMetrics/VictoriaMetrics/lib/prompbmarshal"
"github.com/VictoriaMetrics/VictoriaMetrics/lib/promrelabel"
"github.com/VictoriaMetrics/VictoriaMetrics/lib/timeutil"
"github.com/VictoriaMetrics/metrics"
"github.com/golang/snappy"
)
var (
flushInterval = flag.Duration("remoteWrite.flushInterval", time.Second, "Interval for flushing the data to remote storage. "+
"This option takes effect only when less than 10K data points per second are pushed to -remoteWrite.url")
maxUnpackedBlockSize = flagutil.NewBytes("remoteWrite.maxBlockSize", 8*1024*1024, "The maximum block size to send to remote storage. Bigger blocks may improve performance at the cost of the increased memory usage. See also -remoteWrite.maxRowsPerBlock")
maxRowsPerBlock = flag.Int("remoteWrite.maxRowsPerBlock", 10000, "The maximum number of samples to send in each block to remote storage. Higher number may improve performance at the cost of the increased memory usage. See also -remoteWrite.maxBlockSize")
vmProtoCompressLevel = flag.Int("remoteWrite.vmProtoCompressLevel", 0, "The compression level for VictoriaMetrics remote write protocol. "+
"Higher values reduce network traffic at the cost of higher CPU usage. Negative values reduce CPU usage at the cost of increased network traffic. "+
"See https://docs.victoriametrics.com/vmagent/#victoriametrics-remote-write-protocol")
)
type pendingSeries struct {
mu sync.Mutex
wr writeRequest
stopCh chan struct{}
periodicFlusherWG sync.WaitGroup
}
func newPendingSeries(fq *persistentqueue.FastQueue, isVMRemoteWrite bool, significantFigures, roundDigits int) *pendingSeries {
var ps pendingSeries
ps.wr.fq = fq
ps.wr.isVMRemoteWrite = isVMRemoteWrite
ps.wr.significantFigures = significantFigures
ps.wr.roundDigits = roundDigits
ps.stopCh = make(chan struct{})
ps.periodicFlusherWG.Add(1)
go func() {
defer ps.periodicFlusherWG.Done()
ps.periodicFlusher()
}()
return &ps
}
func (ps *pendingSeries) MustStop() {
close(ps.stopCh)
ps.periodicFlusherWG.Wait()
}
func (ps *pendingSeries) TryPush(tss []prompbmarshal.TimeSeries) bool {
ps.mu.Lock()
ok := ps.wr.tryPush(tss)
ps.mu.Unlock()
return ok
}
func (ps *pendingSeries) periodicFlusher() {
flushSeconds := int64(flushInterval.Seconds())
if flushSeconds <= 0 {
flushSeconds = 1
}
d := timeutil.AddJitterToDuration(*flushInterval)
ticker := time.NewTicker(d)
defer ticker.Stop()
for {
select {
case <-ps.stopCh:
ps.mu.Lock()
ps.wr.mustFlushOnStop()
ps.mu.Unlock()
return
case <-ticker.C:
if fasttime.UnixTimestamp()-ps.wr.lastFlushTime.Load() < uint64(flushSeconds) {
continue
}
}
ps.mu.Lock()
_ = ps.wr.tryFlush()
ps.mu.Unlock()
}
}
type writeRequest struct {
lastFlushTime atomic.Uint64
// The queue to send blocks to.
fq *persistentqueue.FastQueue
// Whether to encode the write request with VictoriaMetrics remote write protocol.
isVMRemoteWrite bool
// How many significant figures must be left before sending the writeRequest to fq.
significantFigures int
// How many decimal digits after point must be left before sending the writeRequest to fq.
roundDigits int
wr prompbmarshal.WriteRequest
tss []prompbmarshal.TimeSeries
labels []prompbmarshal.Label
samples []prompbmarshal.Sample
// buf holds labels data
buf []byte
}
func (wr *writeRequest) reset() {
// Do not reset lastFlushTime, fq, isVMRemoteWrite, significantFigures and roundDigits, since they are re-used.
wr.wr.Timeseries = nil
clear(wr.tss)
wr.tss = wr.tss[:0]
promrelabel.CleanLabels(wr.labels)
wr.labels = wr.labels[:0]
wr.samples = wr.samples[:0]
wr.buf = wr.buf[:0]
}
// mustFlushOnStop force pushes wr data into wr.fq
//
// This is needed in order to properly save in-memory data to persistent queue on graceful shutdown.
func (wr *writeRequest) mustFlushOnStop() {
wr.wr.Timeseries = wr.tss
if !tryPushWriteRequest(&wr.wr, wr.mustWriteBlock, wr.isVMRemoteWrite) {
logger.Panicf("BUG: final flush must always return true")
}
wr.reset()
}
func (wr *writeRequest) mustWriteBlock(block []byte) bool {
wr.fq.MustWriteBlockIgnoreDisabledPQ(block)
return true
}
func (wr *writeRequest) tryFlush() bool {
wr.wr.Timeseries = wr.tss
wr.lastFlushTime.Store(fasttime.UnixTimestamp())
if !tryPushWriteRequest(&wr.wr, wr.fq.TryWriteBlock, wr.isVMRemoteWrite) {
return false
}
wr.reset()
return true
}
func adjustSampleValues(samples []prompbmarshal.Sample, significantFigures, roundDigits int) {
if n := significantFigures; n > 0 {
for i := range samples {
s := &samples[i]
s.Value = decimal.RoundToSignificantFigures(s.Value, n)
}
}
if n := roundDigits; n < 100 {
for i := range samples {
s := &samples[i]
s.Value = decimal.RoundToDecimalDigits(s.Value, n)
}
}
}
func (wr *writeRequest) tryPush(src []prompbmarshal.TimeSeries) bool {
tssDst := wr.tss
maxSamplesPerBlock := *maxRowsPerBlock
// Allow up to 10x of labels per each block on average.
maxLabelsPerBlock := 10 * maxSamplesPerBlock
for i := range src {
if len(wr.samples) >= maxSamplesPerBlock || len(wr.labels) >= maxLabelsPerBlock {
wr.tss = tssDst
if !wr.tryFlush() {
return false
}
tssDst = wr.tss
}
tsSrc := &src[i]
adjustSampleValues(tsSrc.Samples, wr.significantFigures, wr.roundDigits)
tssDst = append(tssDst, prompbmarshal.TimeSeries{})
wr.copyTimeSeries(&tssDst[len(tssDst)-1], tsSrc)
}
wr.tss = tssDst
return true
}
func (wr *writeRequest) copyTimeSeries(dst, src *prompbmarshal.TimeSeries) {
labelsDst := wr.labels
labelsLen := len(wr.labels)
samplesDst := wr.samples
buf := wr.buf
for i := range src.Labels {
labelsDst = append(labelsDst, prompbmarshal.Label{})
dstLabel := &labelsDst[len(labelsDst)-1]
srcLabel := &src.Labels[i]
buf = append(buf, srcLabel.Name...)
dstLabel.Name = bytesutil.ToUnsafeString(buf[len(buf)-len(srcLabel.Name):])
buf = append(buf, srcLabel.Value...)
dstLabel.Value = bytesutil.ToUnsafeString(buf[len(buf)-len(srcLabel.Value):])
}
dst.Labels = labelsDst[labelsLen:]
samplesDst = append(samplesDst, src.Samples...)
dst.Samples = samplesDst[len(samplesDst)-len(src.Samples):]
wr.samples = samplesDst
wr.labels = labelsDst
wr.buf = buf
}
// marshalConcurrency limits the maximum number of concurrent workers, which marshal and compress WriteRequest.
var marshalConcurrencyCh = make(chan struct{}, cgroup.AvailableCPUs())
func tryPushWriteRequest(wr *prompbmarshal.WriteRequest, tryPushBlock func(block []byte) bool, isVMRemoteWrite bool) bool {
if len(wr.Timeseries) == 0 {
// Nothing to push
return true
}
marshalConcurrencyCh <- struct{}{}
bb := writeRequestBufPool.Get()
bb.B = wr.MarshalProtobuf(bb.B[:0])
if len(bb.B) <= maxUnpackedBlockSize.IntN() {
zb := compressBufPool.Get()
if isVMRemoteWrite {
zb.B = zstd.CompressLevel(zb.B[:0], bb.B, *vmProtoCompressLevel)
} else {
zb.B = snappy.Encode(zb.B[:cap(zb.B)], bb.B)
}
writeRequestBufPool.Put(bb)
<-marshalConcurrencyCh
if len(zb.B) <= persistentqueue.MaxBlockSize {
zbLen := len(zb.B)
ok := tryPushBlock(zb.B)
compressBufPool.Put(zb)
if ok {
blockSizeRows.Update(float64(len(wr.Timeseries)))
blockSizeBytes.Update(float64(zbLen))
}
return ok
}
compressBufPool.Put(zb)
} else {
writeRequestBufPool.Put(bb)
<-marshalConcurrencyCh
}
// Too big block. Recursively split it into smaller parts if possible.
if len(wr.Timeseries) == 1 {
// A single time series left. Recursively split its samples into smaller parts if possible.
samples := wr.Timeseries[0].Samples
if len(samples) == 1 {
logger.Warnf("dropping a sample for metric with too long labels exceeding -remoteWrite.maxBlockSize=%d bytes", maxUnpackedBlockSize.N)
return true
}
n := len(samples) / 2
wr.Timeseries[0].Samples = samples[:n]
if !tryPushWriteRequest(wr, tryPushBlock, isVMRemoteWrite) {
wr.Timeseries[0].Samples = samples
return false
}
wr.Timeseries[0].Samples = samples[n:]
if !tryPushWriteRequest(wr, tryPushBlock, isVMRemoteWrite) {
wr.Timeseries[0].Samples = samples
return false
}
wr.Timeseries[0].Samples = samples
return true
}
timeseries := wr.Timeseries
n := len(timeseries) / 2
wr.Timeseries = timeseries[:n]
if !tryPushWriteRequest(wr, tryPushBlock, isVMRemoteWrite) {
wr.Timeseries = timeseries
return false
}
wr.Timeseries = timeseries[n:]
if !tryPushWriteRequest(wr, tryPushBlock, isVMRemoteWrite) {
wr.Timeseries = timeseries
return false
}
wr.Timeseries = timeseries
return true
}
var (
blockSizeBytes = metrics.NewHistogram(`vmagent_remotewrite_block_size_bytes`)
blockSizeRows = metrics.NewHistogram(`vmagent_remotewrite_block_size_rows`)
)
var (
writeRequestBufPool bytesutil.ByteBufferPool
compressBufPool bytesutil.ByteBufferPool
)