VictoriaMetrics/app/vmselect/main.go
Aliaksandr Valialkin b05f6cf11c app/vmselect: limit the default value for -search.maxConcurrentRequests, so it plays well on systems with more than 16 vCPUs
A single heavy request can saturate all the available CPUs, so let's limit the number of concurrent requests to lower value.
This will give more chances for executing insert path.
2020-01-17 16:16:43 +02:00

333 lines
12 KiB
Go

package main
import (
"flag"
"fmt"
"net/http"
"runtime"
"strings"
"time"
"github.com/VictoriaMetrics/VictoriaMetrics/app/vmselect/netstorage"
"github.com/VictoriaMetrics/VictoriaMetrics/app/vmselect/prometheus"
"github.com/VictoriaMetrics/VictoriaMetrics/app/vmselect/promql"
"github.com/VictoriaMetrics/VictoriaMetrics/lib/auth"
"github.com/VictoriaMetrics/VictoriaMetrics/lib/buildinfo"
"github.com/VictoriaMetrics/VictoriaMetrics/lib/flagutil"
"github.com/VictoriaMetrics/VictoriaMetrics/lib/fs"
"github.com/VictoriaMetrics/VictoriaMetrics/lib/httpserver"
"github.com/VictoriaMetrics/VictoriaMetrics/lib/logger"
"github.com/VictoriaMetrics/VictoriaMetrics/lib/procutil"
"github.com/VictoriaMetrics/VictoriaMetrics/lib/timerpool"
"github.com/VictoriaMetrics/metrics"
)
var (
httpListenAddr = flag.String("httpListenAddr", ":8481", "Address to listen for http connections")
cacheDataPath = flag.String("cacheDataPath", "", "Path to directory for cache files. Cache isn't saved if empty")
maxConcurrentRequests = flag.Int("search.maxConcurrentRequests", getDefaultMaxConcurrentRequests(), "The maximum number of concurrent search requests. "+
"It shouldn't be high, since a single request can saturate all the CPU cores. See also `-search.maxQueueDuration`")
maxQueueDuration = flag.Duration("search.maxQueueDuration", 10*time.Second, "The maximum time the request waits for execution when -search.maxConcurrentRequests limit is reached")
storageNodes = flagutil.NewArray("storageNode", "Addresses of vmstorage nodes; usage: -storageNode=vmstorage-host1:8401 -storageNode=vmstorage-host2:8401")
)
func getDefaultMaxConcurrentRequests() int {
n := runtime.GOMAXPROCS(-1)
if n <= 4 {
n *= 2
}
if n > 16 {
// A single request can saturate all the CPU cores, so there is no sense
// in allowing higher number of concurrent requests - they will just contend
// for unavailable CPU time.
n = 16
}
return n
}
func main() {
flag.Parse()
buildinfo.Init()
logger.Init()
logger.Infof("starting netstorage at storageNodes %s", *storageNodes)
startTime := time.Now()
if len(*storageNodes) == 0 {
logger.Fatalf("missing -storageNode arg")
}
netstorage.InitStorageNodes(*storageNodes)
logger.Infof("started netstorage in %s", time.Since(startTime))
if len(*cacheDataPath) > 0 {
tmpDataPath := *cacheDataPath + "/tmp"
fs.RemoveDirContents(tmpDataPath)
netstorage.InitTmpBlocksDir(tmpDataPath)
promql.InitRollupResultCache(*cacheDataPath + "/rollupResult")
} else {
netstorage.InitTmpBlocksDir("")
promql.InitRollupResultCache("")
}
concurrencyCh = make(chan struct{}, *maxConcurrentRequests)
go func() {
httpserver.Serve(*httpListenAddr, requestHandler)
}()
sig := procutil.WaitForSigterm()
logger.Infof("service received signal %s", sig)
logger.Infof("gracefully shutting down the service at %q", *httpListenAddr)
startTime = time.Now()
if err := httpserver.Stop(*httpListenAddr); err != nil {
logger.Fatalf("cannot stop the service: %s", err)
}
logger.Infof("successfully shut down the service in %s", time.Since(startTime))
logger.Infof("shutting down neststorage...")
startTime = time.Now()
netstorage.Stop()
if len(*cacheDataPath) > 0 {
promql.StopRollupResultCache()
}
logger.Infof("successfully stopped netstorage in %s", time.Since(startTime))
fs.MustStopDirRemover()
logger.Infof("the vmselect has been stopped")
}
var concurrencyCh chan struct{}
var (
concurrencyLimitReached = metrics.NewCounter(`vm_concurrent_select_limit_reached_total`)
concurrencyLimitTimeout = metrics.NewCounter(`vm_concurrent_select_limit_timeout_total`)
_ = metrics.NewGauge(`vm_concurrent_select_capacity`, func() float64 {
return float64(cap(concurrencyCh))
})
_ = metrics.NewGauge(`vm_concurrent_select_current`, func() float64 {
return float64(len(concurrencyCh))
})
)
func requestHandler(w http.ResponseWriter, r *http.Request) bool {
// Limit the number of concurrent queries.
select {
case concurrencyCh <- struct{}{}:
defer func() { <-concurrencyCh }()
default:
// Sleep for a while until giving up. This should resolve short bursts in requests.
concurrencyLimitReached.Inc()
t := timerpool.Get(*maxQueueDuration)
select {
case concurrencyCh <- struct{}{}:
timerpool.Put(t)
defer func() { <-concurrencyCh }()
case <-t.C:
timerpool.Put(t)
concurrencyLimitTimeout.Inc()
err := &httpserver.ErrorWithStatusCode{
Err: fmt.Errorf("cannot handle more than %d concurrent search requests during %s; possible solutions: "+
"increase `-search.maxQueueDuration`, increase `-search.maxConcurrentRequests`, increase server capacity",
*maxConcurrentRequests, *maxQueueDuration),
StatusCode: http.StatusServiceUnavailable,
}
httpserver.Errorf(w, "%s", err)
return true
}
}
path := r.URL.Path
if path == "/internal/resetRollupResultCache" {
promql.ResetRollupResultCache()
return true
}
p, err := httpserver.ParsePath(path)
if err != nil {
httpserver.Errorf(w, "cannot parse path %q: %s", path, err)
return true
}
at, err := auth.NewToken(p.AuthToken)
if err != nil {
httpserver.Errorf(w, "auth error: %s", err)
return true
}
switch p.Prefix {
case "select":
return selectHandler(w, r, p, at)
case "delete":
return deleteHandler(w, r, p, at)
default:
// This is not our link
return false
}
}
func selectHandler(w http.ResponseWriter, r *http.Request, p *httpserver.Path, at *auth.Token) bool {
if strings.HasPrefix(p.Suffix, "prometheus/api/v1/label/") {
s := p.Suffix[len("prometheus/api/v1/label/"):]
if strings.HasSuffix(s, "/values") {
labelValuesRequests.Inc()
labelName := s[:len(s)-len("/values")]
httpserver.EnableCORS(w, r)
if err := prometheus.LabelValuesHandler(at, labelName, w, r); err != nil {
labelValuesErrors.Inc()
sendPrometheusError(w, r, err)
return true
}
return true
}
}
switch p.Suffix {
case "prometheus/api/v1/query":
queryRequests.Inc()
httpserver.EnableCORS(w, r)
if err := prometheus.QueryHandler(at, w, r); err != nil {
queryErrors.Inc()
sendPrometheusError(w, r, err)
return true
}
return true
case "prometheus/api/v1/query_range":
queryRangeRequests.Inc()
httpserver.EnableCORS(w, r)
if err := prometheus.QueryRangeHandler(at, w, r); err != nil {
queryRangeErrors.Inc()
sendPrometheusError(w, r, err)
return true
}
return true
case "prometheus/api/v1/series":
seriesRequests.Inc()
httpserver.EnableCORS(w, r)
if err := prometheus.SeriesHandler(at, w, r); err != nil {
seriesErrors.Inc()
sendPrometheusError(w, r, err)
return true
}
return true
case "prometheus/api/v1/series/count":
seriesCountRequests.Inc()
httpserver.EnableCORS(w, r)
if err := prometheus.SeriesCountHandler(at, w, r); err != nil {
seriesCountErrors.Inc()
sendPrometheusError(w, r, err)
return true
}
return true
case "prometheus/api/v1/labels":
labelsRequests.Inc()
httpserver.EnableCORS(w, r)
if err := prometheus.LabelsHandler(at, w, r); err != nil {
labelsErrors.Inc()
sendPrometheusError(w, r, err)
return true
}
return true
case "prometheus/api/v1/labels/count":
labelsCountRequests.Inc()
httpserver.EnableCORS(w, r)
if err := prometheus.LabelsCountHandler(at, w, r); err != nil {
labelsCountErrors.Inc()
sendPrometheusError(w, r, err)
return true
}
return true
case "prometheus/api/v1/export":
exportRequests.Inc()
if err := prometheus.ExportHandler(at, w, r); err != nil {
exportErrors.Inc()
httpserver.Errorf(w, "error in %q: %s", r.URL.Path, err)
return true
}
return true
case "prometheus/federate":
federateRequests.Inc()
if err := prometheus.FederateHandler(at, w, r); err != nil {
federateErrors.Inc()
httpserver.Errorf(w, "error in %q: %s", r.URL.Path, err)
return true
}
return true
case "prometheus/api/v1/rules":
// Return dumb placeholder
rulesRequests.Inc()
w.Header().Set("Content-Type", "application/json")
fmt.Fprintf(w, "%s", `{"status":"success","data":{"groups":[]}}`)
return true
case "prometheus/api/v1/alerts":
// Return dumb placehloder
alertsRequests.Inc()
w.Header().Set("Content-Type", "application/json")
fmt.Fprintf(w, "%s", `{"status":"success","data":{"alerts":[]}}`)
return true
default:
return false
}
}
func deleteHandler(w http.ResponseWriter, r *http.Request, p *httpserver.Path, at *auth.Token) bool {
switch p.Suffix {
case "prometheus/api/v1/admin/tsdb/delete_series":
deleteRequests.Inc()
if err := prometheus.DeleteHandler(at, r); err != nil {
deleteErrors.Inc()
httpserver.Errorf(w, "error in %q: %s", r.URL.Path, err)
return true
}
w.WriteHeader(http.StatusNoContent)
return true
default:
return false
}
}
func sendPrometheusError(w http.ResponseWriter, r *http.Request, err error) {
logger.Errorf("error in %q: %s", r.URL.Path, err)
w.Header().Set("Content-Type", "application/json")
statusCode := http.StatusUnprocessableEntity
if esc, ok := err.(*httpserver.ErrorWithStatusCode); ok {
statusCode = esc.StatusCode
}
w.WriteHeader(statusCode)
prometheus.WriteErrorResponse(w, statusCode, err)
}
var (
labelValuesRequests = metrics.NewCounter(`vm_http_requests_total{path="/select/{}/prometheus/api/v1/label/{}/values"}`)
labelValuesErrors = metrics.NewCounter(`vm_http_request_errors_total{path="select/{}/prometheus/api/v1/label/{}/values"}`)
queryRequests = metrics.NewCounter(`vm_http_requests_total{path="/select/{}/prometheus/api/v1/query"}`)
queryErrors = metrics.NewCounter(`vm_http_request_errors_total{path="/select/{}/prometheus/api/v1/query"}`)
queryRangeRequests = metrics.NewCounter(`vm_http_requests_total{path="/select/prometheus/api/v1/query_range"}`)
queryRangeErrors = metrics.NewCounter(`vm_http_request_errors_total{path="/select/{}/prometheus/api/v1/query_range"}`)
seriesRequests = metrics.NewCounter(`vm_http_requests_total{path="/select/{}/prometheus/api/v1/series"}`)
seriesErrors = metrics.NewCounter(`vm_http_request_errors_total{path="/select/{}/prometheus/api/v1/series"}`)
seriesCountRequests = metrics.NewCounter(`vm_http_requests_total{path="/select/{}/prometheus/api/v1/series/count"}`)
seriesCountErrors = metrics.NewCounter(`vm_http_request_errors_total{path="/select/{}/prometheus/api/v1/series/count"}`)
labelsRequests = metrics.NewCounter(`vm_http_requests_total{path="/select/{}/prometheus/api/v1/labels"}`)
labelsErrors = metrics.NewCounter(`vm_http_request_errors_total{path="/select/{}/prometheus/api/v1/labels"}`)
labelsCountRequests = metrics.NewCounter(`vm_http_requests_total{path="/select/{}/prometheus/api/v1/labels/count"}`)
labelsCountErrors = metrics.NewCounter(`vm_http_request_errors_total{path="/select/{}/prometheus/api/v1/labels/count"}`)
deleteRequests = metrics.NewCounter(`vm_http_requests_total{path="/delete/{}/prometheus/api/v1/admin/tsdb/delete_series"}`)
deleteErrors = metrics.NewCounter(`vm_http_request_errors_total{path="/delete/{}/prometheus/api/v1/admin/tsdb/delete_series"}`)
exportRequests = metrics.NewCounter(`vm_http_requests_total{path="/select/{}/prometheus/api/v1/export"}`)
exportErrors = metrics.NewCounter(`vm_http_request_errors_total{path="/select/{}/prometheus/api/v1/export"}`)
federateRequests = metrics.NewCounter(`vm_http_requests_total{path="/select/{}/prometheus/federate"}`)
federateErrors = metrics.NewCounter(`vm_http_request_errors_total{path="/select/{}/prometheus/federate"}`)
rulesRequests = metrics.NewCounter(`vm_http_requests_total{path="/select/{}/prometheus/api/v1/rules"}`)
alertsRequests = metrics.NewCounter(`vm_http_requests_total{path="/select/{}/prometheus/api/v1/alerts"}`)
)