VictoriaMetrics/lib/promscrape/scrapework_timing_test.go
Aliaksandr Valialkin 09c388a8e4
lib/promscrape: use the standard net/http.Client instead of fasthttp.Client for scraping targets in non-streaming mode
While fasthttp.Client uses less CPU and RAM when scraping targets with small responses (up to 10K metrics),
it doesn't work well when scraping targets with big responses such as kube-state-metrics.
In this case it could use big amounts of additional memory comparing to net/http.Client,
since fasthttp.Client reads the full response in memory and then tries re-using the large buffer
for further scrapes.

Additionally, fasthttp.Client-based scraping had various issues with proxying, redirects
and scrape timeouts like the following ones:

- https://github.com/VictoriaMetrics/VictoriaMetrics/issues/1945
- https://github.com/VictoriaMetrics/VictoriaMetrics/issues/5425
- https://github.com/VictoriaMetrics/VictoriaMetrics/issues/2794
- https://github.com/VictoriaMetrics/VictoriaMetrics/issues/1017

This should help reducing memory usage for the case when target returns big response
and this response is scraped by fasthttp.Client at first before switching to stream parsing mode
for subsequent scrapes. Now the switch to stream parsing mode is performed on the first scrape
after reading the response body in memory and noticing that its size exceeds the value passed
to -promscrape.minResponseSizeForStreamParse command-line flag.
Updates https://github.com/VictoriaMetrics/VictoriaMetrics/issues/5567

Overrides https://github.com/VictoriaMetrics/VictoriaMetrics/pull/4931
2024-01-30 18:39:55 +02:00

98 lines
3 KiB
Go

package promscrape
import (
"fmt"
"testing"
"github.com/VictoriaMetrics/VictoriaMetrics/lib/auth"
"github.com/VictoriaMetrics/VictoriaMetrics/lib/bytesutil"
"github.com/VictoriaMetrics/VictoriaMetrics/lib/prompbmarshal"
)
func BenchmarkIsAutoMetricMiss(b *testing.B) {
metrics := []string{
"process_cpu_seconds_total",
"process_resident_memory_bytes",
"vm_tcplistener_read_calls_total",
"http_requests_total",
"node_cpu_seconds_total",
}
b.ReportAllocs()
b.SetBytes(1)
b.RunParallel(func(pb *testing.PB) {
for pb.Next() {
for _, metric := range metrics {
if isAutoMetric(metric) {
panic(fmt.Errorf("BUG: %q mustn't be detected as auto metric", metric))
}
}
}
})
}
func BenchmarkIsAutoMetricHit(b *testing.B) {
metrics := []string{
"up",
"scrape_duration_seconds",
"scrape_series_current",
"scrape_samples_scraped",
"scrape_series_added",
}
b.ReportAllocs()
b.SetBytes(1)
b.RunParallel(func(pb *testing.PB) {
for pb.Next() {
for _, metric := range metrics {
if !isAutoMetric(metric) {
panic(fmt.Errorf("BUG: %q must be detected as auto metric", metric))
}
}
}
})
}
func BenchmarkScrapeWorkScrapeInternal(b *testing.B) {
data := `
vm_tcplistener_accepts_total{name="http", addr=":80"} 1443
vm_tcplistener_accepts_total{name="https", addr=":443"} 12801
vm_tcplistener_conns{name="http", addr=":80"} 0
vm_tcplistener_conns{name="https", addr=":443"} 2
vm_tcplistener_errors_total{name="http", addr=":80", type="accept"} 0
vm_tcplistener_errors_total{name="http", addr=":80", type="close"} 0
vm_tcplistener_errors_total{name="http", addr=":80", type="read"} 97
vm_tcplistener_errors_total{name="http", addr=":80", type="write"} 2
vm_tcplistener_errors_total{name="https", addr=":443", type="accept"} 0
vm_tcplistener_errors_total{name="https", addr=":443", type="close"} 0
vm_tcplistener_errors_total{name="https", addr=":443", type="read"} 243
vm_tcplistener_errors_total{name="https", addr=":443", type="write"} 285
vm_tcplistener_read_bytes_total{name="http", addr=":80"} 879339
vm_tcplistener_read_bytes_total{name="https", addr=":443"} 19453340
vm_tcplistener_read_calls_total{name="http", addr=":80"} 7780
vm_tcplistener_read_calls_total{name="https", addr=":443"} 70323
vm_tcplistener_read_timeouts_total{name="http", addr=":80"} 673
vm_tcplistener_read_timeouts_total{name="https", addr=":443"} 12353
vm_tcplistener_write_calls_total{name="http", addr=":80"} 3996
vm_tcplistener_write_calls_total{name="https", addr=":443"} 132356
`
readDataFunc := func(dst *bytesutil.ByteBuffer) error {
dst.B = append(dst.B, data...)
return nil
}
b.ReportAllocs()
b.SetBytes(int64(len(data)))
b.RunParallel(func(pb *testing.PB) {
var sw scrapeWork
sw.Config = &ScrapeWork{}
sw.ReadData = readDataFunc
sw.PushData = func(at *auth.Token, wr *prompbmarshal.WriteRequest) {}
tsmGlobal.Register(&sw)
timestamp := int64(0)
for pb.Next() {
if err := sw.scrapeInternal(timestamp, timestamp); err != nil {
panic(fmt.Errorf("unexpected error: %w", err))
}
timestamp++
}
tsmGlobal.Unregister(&sw)
})
}