VictoriaMetrics/app/vmagent/remotewrite/remotewrite.go

275 lines
9.6 KiB
Go

package remotewrite
import (
"flag"
"fmt"
"sync"
"sync/atomic"
"github.com/VictoriaMetrics/VictoriaMetrics/lib/cgroup"
"github.com/VictoriaMetrics/VictoriaMetrics/lib/flagutil"
"github.com/VictoriaMetrics/VictoriaMetrics/lib/logger"
"github.com/VictoriaMetrics/VictoriaMetrics/lib/memory"
"github.com/VictoriaMetrics/VictoriaMetrics/lib/persistentqueue"
"github.com/VictoriaMetrics/VictoriaMetrics/lib/procutil"
"github.com/VictoriaMetrics/VictoriaMetrics/lib/prompbmarshal"
"github.com/VictoriaMetrics/metrics"
xxhash "github.com/cespare/xxhash/v2"
)
var (
remoteWriteURLs = flagutil.NewArray("remoteWrite.url", "Remote storage URL to write data to. It must support Prometheus remote_write API. "+
"It is recommended using VictoriaMetrics as remote storage. Example url: http://<victoriametrics-host>:8428/api/v1/write . "+
"Pass multiple -remoteWrite.url flags in order to write data concurrently to multiple remote storage systems")
tmpDataPath = flag.String("remoteWrite.tmpDataPath", "vmagent-remotewrite-data", "Path to directory where temporary data for remote write component is stored. "+
"See also -remoteWrite.maxDiskUsagePerURL")
queues = flag.Int("remoteWrite.queues", 4, "The number of concurrent queues to each -remoteWrite.url. Set more queues if default number of queues "+
"isn't enough for sending high volume of collected data to remote storage")
showRemoteWriteURL = flag.Bool("remoteWrite.showURL", false, "Whether to show -remoteWrite.url in the exported metrics. "+
"It is hidden by default, since it can contain sensitive info such as auth key")
maxPendingBytesPerURL = flagutil.NewBytes("remoteWrite.maxDiskUsagePerURL", 0, "The maximum file-based buffer size in bytes at -remoteWrite.tmpDataPath "+
"for each -remoteWrite.url. When buffer size reaches the configured maximum, then old data is dropped when adding new data to the buffer. "+
"Buffered data is stored in ~500MB chunks, so the minimum practical value for this flag is 500000000. "+
"Disk usage is unlimited if the value is set to 0")
significantFigures = flagutil.NewArrayInt("remoteWrite.significantFigures", "The number of significant figures to leave in metric values before writing them "+
"to remote storage. See https://en.wikipedia.org/wiki/Significant_figures . Zero value saves all the significant figures. "+
"This option may be used for improving data compression for the stored metrics. See also -remoteWrite.roundDigits")
roundDigits = flagutil.NewArrayInt("remoteWrite.roundDigits", "Round metric values to this number of decimal digits after the point before writing them to remote storage. "+
"Examples: -remoteWrite.roundDigits=2 would round 1.236 to 1.24, while -remoteWrite.roundDigits=-1 would round 126.78 to 130. "+
"By default digits rounding is disabled. Set it to 100 for disabling it for a particular remote storage. "+
"This option may be used for improving data compression for the stored metrics")
)
var rwctxs []*remoteWriteCtx
// Contains the current relabelConfigs.
var allRelabelConfigs atomic.Value
// maxQueues limits the maximum value for `-remoteWrite.queues`. There is no sense in setting too high value,
// since it may lead to high memory usage due to big number of buffers.
var maxQueues = cgroup.AvailableCPUs() * 4
// InitSecretFlags must be called after flag.Parse and before any logging.
func InitSecretFlags() {
if !*showRemoteWriteURL {
// remoteWrite.url can contain authentication codes, so hide it at `/metrics` output.
flagutil.RegisterSecretFlag("remoteWrite.url")
}
}
// Init initializes remotewrite.
//
// It must be called after flag.Parse().
//
// Stop must be called for graceful shutdown.
func Init() {
if len(*remoteWriteURLs) == 0 {
logger.Fatalf("at least one `-remoteWrite.url` command-line flag must be set")
}
if *queues > maxQueues {
*queues = maxQueues
}
if *queues <= 0 {
*queues = 1
}
initLabelsGlobal()
rcs, err := loadRelabelConfigs()
if err != nil {
logger.Fatalf("cannot load relabel configs: %s", err)
}
allRelabelConfigs.Store(rcs)
maxInmemoryBlocks := memory.Allowed() / len(*remoteWriteURLs) / maxRowsPerBlock / 100
if maxInmemoryBlocks > 200 {
// There is no much sense in keeping higher number of blocks in memory,
// since this means that the producer outperforms consumer and the queue
// will continue growing. It is better storing the queue to file.
maxInmemoryBlocks = 200
}
if maxInmemoryBlocks < 2 {
maxInmemoryBlocks = 2
}
for i, remoteWriteURL := range *remoteWriteURLs {
sanitizedURL := fmt.Sprintf("%d:secret-url", i+1)
if *showRemoteWriteURL {
sanitizedURL = fmt.Sprintf("%d:%s", i+1, remoteWriteURL)
}
rwctx := newRemoteWriteCtx(i, remoteWriteURL, maxInmemoryBlocks, sanitizedURL)
rwctxs = append(rwctxs, rwctx)
}
// Start config reloader.
sighupCh := procutil.NewSighupChan()
configReloaderWG.Add(1)
go func() {
defer configReloaderWG.Done()
for {
select {
case <-sighupCh:
case <-stopCh:
return
}
logger.Infof("SIGHUP received; reloading relabel configs pointed by -remoteWrite.relabelConfig and -remoteWrite.urlRelabelConfig")
rcs, err := loadRelabelConfigs()
if err != nil {
logger.Errorf("cannot reload relabel configs; preserving the previous configs; error: %s", err)
continue
}
allRelabelConfigs.Store(rcs)
logger.Infof("Successfully reloaded relabel configs")
}
}()
}
var stopCh = make(chan struct{})
var configReloaderWG sync.WaitGroup
// Stop stops remotewrite.
//
// It is expected that nobody calls Push during and after the call to this func.
func Stop() {
close(stopCh)
configReloaderWG.Wait()
for _, rwctx := range rwctxs {
rwctx.MustStop()
}
rwctxs = nil
}
// Push sends wr to remote storage systems set via `-remoteWrite.url`.
//
// Note that wr may be modified by Push due to relabeling and rounding.
func Push(wr *prompbmarshal.WriteRequest) {
var rctx *relabelCtx
rcs := allRelabelConfigs.Load().(*relabelConfigs)
pcsGlobal := rcs.global
if pcsGlobal.Len() > 0 || len(labelsGlobal) > 0 {
rctx = getRelabelCtx()
}
tss := wr.Timeseries
for len(tss) > 0 {
// Process big tss in smaller blocks in order to reduce the maximum memory usage
samplesCount := 0
labelsCount := 0
i := 0
for i < len(tss) {
samplesCount += len(tss[i].Samples)
labelsCount += len(tss[i].Labels)
i++
if samplesCount >= maxRowsPerBlock || labelsCount >= maxLabelsPerBlock {
break
}
}
tssBlock := tss
if i < len(tss) {
tssBlock = tss[:i]
tss = tss[i:]
} else {
tss = nil
}
if rctx != nil {
tssBlockLen := len(tssBlock)
tssBlock = rctx.applyRelabeling(tssBlock, labelsGlobal, pcsGlobal)
globalRelabelMetricsDropped.Add(tssBlockLen - len(tssBlock))
}
for _, rwctx := range rwctxs {
rwctx.Push(tssBlock)
}
if rctx != nil {
rctx.reset()
}
}
if rctx != nil {
putRelabelCtx(rctx)
}
}
var globalRelabelMetricsDropped = metrics.NewCounter("vmagent_remotewrite_global_relabel_metrics_dropped_total")
type remoteWriteCtx struct {
idx int
fq *persistentqueue.FastQueue
c *client
pss []*pendingSeries
pssNextIdx uint64
relabelMetricsDropped *metrics.Counter
}
func newRemoteWriteCtx(argIdx int, remoteWriteURL string, maxInmemoryBlocks int, sanitizedURL string) *remoteWriteCtx {
h := xxhash.Sum64([]byte(remoteWriteURL))
path := fmt.Sprintf("%s/persistent-queue/%d_%016X", *tmpDataPath, argIdx+1, h)
fq := persistentqueue.MustOpenFastQueue(path, sanitizedURL, maxInmemoryBlocks, maxPendingBytesPerURL.N)
_ = metrics.GetOrCreateGauge(fmt.Sprintf(`vmagent_remotewrite_pending_data_bytes{path=%q, url=%q}`, path, sanitizedURL), func() float64 {
return float64(fq.GetPendingBytes())
})
_ = metrics.GetOrCreateGauge(fmt.Sprintf(`vmagent_remotewrite_pending_inmemory_blocks{path=%q, url=%q}`, path, sanitizedURL), func() float64 {
return float64(fq.GetInmemoryQueueLen())
})
c := newClient(argIdx, remoteWriteURL, sanitizedURL, fq, *queues)
sf := significantFigures.GetOptionalArgOrDefault(argIdx, 0)
rd := roundDigits.GetOptionalArgOrDefault(argIdx, 100)
pss := make([]*pendingSeries, *queues)
for i := range pss {
pss[i] = newPendingSeries(fq.MustWriteBlock, sf, rd)
}
return &remoteWriteCtx{
idx: argIdx,
fq: fq,
c: c,
pss: pss,
relabelMetricsDropped: metrics.GetOrCreateCounter(fmt.Sprintf(`vmagent_remotewrite_relabel_metrics_dropped_total{path=%q, url=%q}`, path, sanitizedURL)),
}
}
func (rwctx *remoteWriteCtx) MustStop() {
for _, ps := range rwctx.pss {
ps.MustStop()
}
rwctx.idx = 0
rwctx.pss = nil
rwctx.fq.UnblockAllReaders()
rwctx.c.MustStop()
rwctx.c = nil
rwctx.fq.MustClose()
rwctx.fq = nil
rwctx.relabelMetricsDropped = nil
}
func (rwctx *remoteWriteCtx) Push(tss []prompbmarshal.TimeSeries) {
var rctx *relabelCtx
var v *[]prompbmarshal.TimeSeries
rcs := allRelabelConfigs.Load().(*relabelConfigs)
pcs := rcs.perURL[rwctx.idx]
if pcs.Len() > 0 {
rctx = getRelabelCtx()
// Make a copy of tss before applying relabeling in order to prevent
// from affecting time series for other remoteWrite.url configs.
// See https://github.com/VictoriaMetrics/VictoriaMetrics/issues/467
// and https://github.com/VictoriaMetrics/VictoriaMetrics/issues/599
v = tssRelabelPool.Get().(*[]prompbmarshal.TimeSeries)
tss = append(*v, tss...)
tssLen := len(tss)
tss = rctx.applyRelabeling(tss, nil, pcs)
rwctx.relabelMetricsDropped.Add(tssLen - len(tss))
}
pss := rwctx.pss
idx := atomic.AddUint64(&rwctx.pssNextIdx, 1) % uint64(len(pss))
pss[idx].Push(tss)
if rctx != nil {
*v = prompbmarshal.ResetTimeSeries(tss)
tssRelabelPool.Put(v)
putRelabelCtx(rctx)
}
}
var tssRelabelPool = &sync.Pool{
New: func() interface{} {
a := []prompbmarshal.TimeSeries{}
return &a
},
}