Skip to content

rate limit log pattern extraction to cap CPU usage under log storms #360

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Merged
def merged 1 commit into from
Aug 10, 2026
Merged

rate limit log pattern extraction to cap CPU usage under log storms #360

Show file tree
Hide file tree
Changes from all commits
Commits
Show all changes
1 commit
Select commit
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
6 changes: 3 additions & 3 deletions containers/container.go
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -1249,7 +1249,7 @@ func (c *Container) runLogParser(logPath string) {
return
}
ch := make(chan logparser.LogEntry)
parser := logparser.NewParser(ch, nil, logs.OtelLogEmitter(containerId), logs.MultilineCollectorTimeout, *flags.LogPatternsPerContainer, !*flags.DisableJsonLogParsing)
parser := logparser.NewParser(ch, nil, logs.OtelLogEmitter(containerId), logs.MultilineCollectorTimeout, *flags.LogPatternsPerContainer, !*flags.DisableJsonLogParsing, logs.PatternExtractionRateLimiter())
reader, err := logs.NewTailReader(proc.HostPath(logPath), ch)
if err != nil {
klog.Warningln(err)
Expand All @@ -1268,7 +1268,7 @@ func (c *Container) runLogParser(logPath string) {
klog.Warningln(err)
return
}
parser := logparser.NewParser(ch, nil, logs.OtelLogEmitter(containerId), logs.MultilineCollectorTimeout, *flags.LogPatternsPerContainer, !*flags.DisableJsonLogParsing)
parser := logparser.NewParser(ch, nil, logs.OtelLogEmitter(containerId), logs.MultilineCollectorTimeout, *flags.LogPatternsPerContainer, !*flags.DisableJsonLogParsing, logs.PatternExtractionRateLimiter())
stop := func() {
JournaldUnsubscribe(c.metadata.systemd.Unit)
}
Expand All @@ -1284,7 +1284,7 @@ func (c *Container) runLogParser(logPath string) {
delete(c.logParsers, "stdout/stderr")
}
ch := make(chan logparser.LogEntry)
parser := logparser.NewParser(ch, c.metadata.logDecoder, logs.OtelLogEmitter(containerId), logs.MultilineCollectorTimeout, *flags.LogPatternsPerContainer, !*flags.DisableJsonLogParsing)
parser := logparser.NewParser(ch, c.metadata.logDecoder, logs.OtelLogEmitter(containerId), logs.MultilineCollectorTimeout, *flags.LogPatternsPerContainer, !*flags.DisableJsonLogParsing, logs.PatternExtractionRateLimiter())
reader, err := logs.NewTailReader(proc.HostPath(c.metadata.logPath), ch)
if err != nil {
klog.Warningln(err)
Expand Down
5 changes: 3 additions & 2 deletions flags/flags.go
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -35,8 +35,9 @@ var (
InstanceType = kingpin.Flag("instance-type", "`instance_type` label for `node_cloud_info` metric").Envar(envar("INSTANCE_TYPE")).String()
InstanceLifeCycle = kingpin.Flag("instance-life-cycle", "`instance_life_cycle` label for `node_cloud_info` metric").Envar(envar("INSTANCE_LIFE_CYCLE")).String()

LogPatternsPerContainer = kingpin.Flag("log-patterns-per-container", "Max unique log patterns per container per level").Default("256").Envar(envar("LOG_PATTERNS_PER_CONTAINER")).Int()
MaxLabelLength = kingpin.Flag("max-label-length", "Maximum length of a metric label value").Default("4096").Envar(envar("MAX_LABEL_LENGTH")).Int()
LogPatternsPerContainer = kingpin.Flag("log-patterns-per-container", "Max unique log patterns per container per level").Default("256").Envar(envar("LOG_PATTERNS_PER_CONTAINER")).Int()
LogPatternExtractionLimit = kingpin.Flag("log-pattern-extraction-limit", "Max log messages per second per container for which patterns are extracted. Over-limit messages are counted under a dedicated 'event was sampled' pattern (0 - unlimited)").Default("100").Envar(envar("LOG_PATTERN_EXTRACTION_LIMIT")).Float64()
MaxLabelLength = kingpin.Flag("max-label-length", "Maximum length of a metric label value").Default("4096").Envar(envar("MAX_LABEL_LENGTH")).Int()

CollectorEndpoint = kingpin.Flag("collector-endpoint", "A base endpoint URL for metrics, traces, logs, and profiles").Envar(envar("COLLECTOR_ENDPOINT")).URL()
ApiKey = kingpin.Flag("api-key", "Coroot API key").Envar(envar("API_KEY")).String()
Expand Down
2 changes: 1 addition & 1 deletion go.mod
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -11,7 +11,7 @@ require (
github.com/containerd/cgroups v1.1.0
github.com/containerd/containerd v1.7.29
github.com/coreos/go-systemd/v22 v22.7.0
github.com/coroot/logparser v1.3.2
github.com/coroot/logparser v1.4.0
github.com/docker/docker v27.4.0+incompatible
github.com/florianl/go-conntrack v0.3.0
github.com/go-kit/log v0.2.1
Expand Down
4 changes: 2 additions & 2 deletions go.sum
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -92,8 +92,8 @@ github.com/coreos/go-systemd/v22 v22.7.0 h1:LAEzFkke61DFROc7zNLX/WA2i5J8gYqe0rSj
github.com/coreos/go-systemd/v22 v22.7.0/go.mod h1:xNUYtjHu2EDXbsxz1i41wouACIwT7Ybq9o0BQhMwD0w=
github.com/coroot/dotnetdiag v1.2.2 h1:PVP/By8o+xhPjfVolJYcjHLbFQInM7pkaD6/otPLc8Q=
github.com/coroot/dotnetdiag v1.2.2/go.mod h1:veXCMlFzm1yNl7wwJb/ZLxO4WbzhDBoy1VG1XtkH2ls=
github.com/coroot/logparser v1.3.2 h1:5osbFfws9/AYUL2mdX3EU0Gjh4ZJ2NVnPN3M+sqbuQE=
github.com/coroot/logparser v1.3.2/go.mod h1:/7qHU4/I4zWRYIzRchQPehlTzbcMv5HV6cwBqg2zl6I=
github.com/coroot/logparser v1.4.0 h1:/b+XnAh7kuKR1mVSekPCSPpKloWx6wJveHa0HDcXueY=
github.com/coroot/logparser v1.4.0/go.mod h1:5mgr/LIFAEuhxLgnFTtEXVWKthT1l2ZTsPHF6oOGc/E=
github.com/coroot/pyroscope/ebpf v0.0.0-20260804213318-758a0e72af3a h1:whKF1ZhIGcaAn9ZV5hbBSkrw7C5OBgWasZ0bYktOW+U=
github.com/coroot/pyroscope/ebpf v0.0.0-20260804213318-758a0e72af3a/go.mod h1:IepHM9FJ0n3n3k+ZV23Y7vNAfvWI7LDuLqWPO4rB6sQ=
github.com/cpuguy83/go-md2man/v2 v2.0.4/go.mod h1:tgQtvFlXSQOSOSIRvRPT7W67SCa46tRHOmNcaadrF8o=
Expand Down
10 changes: 10 additions & 0 deletions logs/otel.go
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -13,18 +13,28 @@ import (
otelLogs "github.com/agoda-com/opentelemetry-logs-go/logs"
sdk "github.com/agoda-com/opentelemetry-logs-go/sdk/logs"
"github.com/coroot/coroot-node-agent/common"
"github.com/coroot/coroot-node-agent/flags"
"github.com/coroot/logparser"
"go.opentelemetry.io/otel/attribute"
"go.opentelemetry.io/otel/sdk/resource"
semconv "go.opentelemetry.io/otel/semconv/v1.18.0"
"go.opentelemetry.io/otel/trace"
"golang.org/x/time/rate"
"k8s.io/klog/v2"
)

// MultilineCollectorTimeout is how long the log parser waits before deciding a
// multi-line log message is complete.
const MultilineCollectorTimeout = time.Second

func PatternExtractionRateLimiter() *rate.Limiter {
limit := *flags.LogPatternExtractionLimit
if limit <= 0 {
return nil
}
return rate.NewLimiter(rate.Limit(limit), int(limit*10))
}

type Config struct {
Endpoint *url.URL
AuthHeaders map[string]string
Expand Down
4 changes: 2 additions & 2 deletions windows/containers/container.go
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -265,7 +265,7 @@ func (c *Container) eventLogInput() chan logparser.LogEntry {
return c.eventLogCh
}
ch := make(chan logparser.LogEntry, 100)
parser := logparser.NewParser(ch, nil, logs.OtelLogEmitter(c.ID), logs.MultilineCollectorTimeout, *flags.LogPatternsPerContainer, !*flags.DisableJsonLogParsing)
parser := logparser.NewParser(ch, nil, logs.OtelLogEmitter(c.ID), logs.MultilineCollectorTimeout, *flags.LogPatternsPerContainer, !*flags.DisableJsonLogParsing, logs.PatternExtractionRateLimiter())
c.addLogParserLocked(logSourceEventLog, logs.NewPipeline(parser, nil))
c.eventLogCh = ch
return ch
Expand All @@ -279,7 +279,7 @@ func (c *Container) startLogTailer() {
defer c.lock.Unlock()
c.stopLogParserLocked(logSourceStdout)
ch := make(chan logparser.LogEntry, 100)
parser := logparser.NewParser(ch, logparser.DockerJsonDecoder{}, logs.OtelLogEmitter(c.ID), logs.MultilineCollectorTimeout, *flags.LogPatternsPerContainer, !*flags.DisableJsonLogParsing)
parser := logparser.NewParser(ch, logparser.DockerJsonDecoder{}, logs.OtelLogEmitter(c.ID), logs.MultilineCollectorTimeout, *flags.LogPatternsPerContainer, !*flags.DisableJsonLogParsing, logs.PatternExtractionRateLimiter())
reader, err := logs.NewTailReader(c.logPath, ch)
if err != nil {
parser.Stop()
Expand Down
Loading