io.MultiWriter
standard libraryThe 1089th most-called standard-library function by production calls. Called 718 times across 215 modules; 593 of those run outside tests and generated code.
- prod calls
- 593
- non-test, non-generated
- all calls
- 718
- total callsites
- modules
- 215
- distinct callers
- in loop
- 5%
- of prod calls
- in tests
- 17%
- 125 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 →
- Package function100%A direct call to an exported package function, resolved by type.
estimate
Estimated relative cost
Roughly 0.00× the estimated relative cost of fmt.Sprintf . Benchmarked at 43.81 ns/op × 593 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 MultiWriter from notable Go projects. Open one on the map to see what else it hammers.
- Kubernetes 68 11%
- containerd 27 5%
- Docker 15 3%
- HashiCorp 13 2%
- Hugo 10 2%
where it's called
Callsites in the wild
12 representative callsites of 718, prioritizing in-loop and non-test usage. We link to source, never display it.
- in loop
- in loop
- in loop
- in loop
- in loop
-
git-lfs/git-lfs @v1.5.6
in loop - in loop
-
google/gvisor @v0.0.0-20260805052044-b67f1412986c
in loop - in loop
-
klauspost/compress @v1.19.1
in loop -
loft-sh/devpod @v0.6.15
in loop - in loop
top callers
The modules that reach for it
The modules that call MultiWriter most in this snapshot.
- github.com/dagger/dagger355%
- github.com/kubernetes/minikube264%
- k8s.io/minikube264%
- github.com/aliyun/alibabacloud-oss-go-sdk-v2172%
- github.com/GoesToEleven/GolangTraining152%
siblings
More from io
The other most-called functions in this package. See all →