sync.RWMutex.RLock
standard libraryThe 61st most-called standard-library method by production calls. Called 23,337 times across 715 modules; 17,535 of those run outside tests and generated code.
0% in production calls vs 2026-W39 (17,499 → 17,535)
- prod calls
- 17,535
- non-test, non-generated
- all calls
- 23,337
- total callsites
- modules
- 715
- distinct callers
- in loop
- 4%
- of prod calls
- in tests
- 10%
- 2,415 calls
- resolved
- 100%
- to a known target
resolution mix
How each call resolves
How each call was attributed. Only resolved kinds, where the target function is known, count toward the ranking. Interface dispatch and unresolved receivers are reported separately and never guessed. Read the taxonomy →
- Concrete method83%A method on a value whose type is known exactly.
- Embedded method17%Reached through an embedded type.
estimate
Estimated relative cost
Roughly 0.00× the estimated relative cost of fmt.Sprintf . Benchmarked at 3.94 ns/op × 17,535 production calls, normalized so fmt.Sprintf = 1.0.
This is not dollars and not a verdict. Per-op time depends heavily on inputs (argument sizes, contention, patterns), the benchmark ran on a single machine (darwin/arm64 (Apple Silicon), go1.26.0), and static call counts are not runtime frequency. How this is estimated →
who calls this
Notable callers
Production calls into RWMutex.RLock from notable Go projects. Open one on the map to see what else it hammers.
- Kubernetes 1,150 7%
- Grafana 857 5%
- NATS 758 4%
- Cilium 399 2%
- InfluxDB 377 2%
where it's called
Callsites in the wild
12 representative callsites of 23,337, prioritizing in-loop and non-test usage. We link to source, never display it.
- in loop
-
go/storage @v1.68.0
grpc_reader_multi_range.go:1369
in loop -
cockroachdb/cockroach @v19.2.12+incompatible
in loop -
miekg/dns @v0.6.117
cmd/atomdns/handlers/dbfile/retransfer.go:20
in loop - in loop
- in loop
- in loop
- in loop
-
docker/docker @v28.5.2+incompatible
in loop -
etcd-io/etcd @v2.3.8+incompatible
in loop -
fyne.io/fyne @v1.4.3
internal/driver/glfw/loop.go:125
in loop - in loop
top callers
The modules that reach for it
The modules that call RWMutex.RLock most in this snapshot.
- github.com/hyperledger/fabric2,0839%
- github.com/nats-io/nats-server/v21,5016%
- github.com/livekit/livekit1,2705%
- github.com/seaweedfs/seaweedfs6523%
- github.com/kubernetes/kubernetes5532%
siblings
More from sync
The other most-called members in this package. See all →