History

Patrick Ohly 8f4c9c7605 k8s.io/component-base/logs: replace klog text implementation This replaces the klog formatting and message routing with a simpler implementation that uses less code. The main difference is that we skip the entire unused message routing. Instead, the same split output streams as for JSON gets implemented in the io.Writer implementation that gets passed to the textlogger.		2024-01-17 13:50:03 +01:00
..
contextual-logging	logs: add micro benchmarks for argument passing	2022-05-31 08:07:37 +02:00
data	test/integration/logs: use stable struct for unit test	2023-03-07 16:04:32 +01:00
.gitignore	test/integration/logs: update benchmark support	2023-03-07 16:03:48 +01:00
benchmark_test.go	k8s.io/component-base/logs: replace klog text implementation	2024-01-17 13:50:03 +01:00
common_test.go	logs benchmark: really write through pipe	2024-01-12 07:49:17 +01:00
get-logs.sh	test/integration/logs: update benchmark support	2023-03-07 16:03:48 +01:00
load_test.go	component-base/logs: improve handling of re-applying a configuration	2023-07-05 19:08:54 +02:00
load.go	test/integration/logs: use stable struct for unit test	2023-03-07 16:04:32 +01:00
README.md	test/integration/logs: remove useless stats case	2023-03-07 16:04:32 +01:00

README.md

Benchmarking logging

Any major changes to the logging code, whether it is in Kubernetes or in klog, must be benchmarked before and after the change.

Running the benchmark

go test -v -bench=. -benchmem -benchtime=10s .

Real log data

The files under data define test cases for specific aspects of formatting. To test with a log file that represents output under some kind of real load, copy the log file into data/<file name>.log and run benchmarking as described above. -bench=BenchmarkLogging/<file name without .log suffix> can be used to benchmark just the new file.

When using data/v<some number>/<file name>.log, formatting will be done at that log level. Symlinks can be created to simulating writing of the same log data at different levels.

No such real data is included in the Kubernetes repo because of their size. They can be found in the "artifacts" of this https://testgrid.kubernetes.io/sig-instrumentation-tests#kind-json-logging-master Prow job:

artifacts/logs/kind-control-plane/containers
artifacts/logs/kind-*/kubelet.log

With sufficient credentials, gsutil can be used to download everything for a job directly into a directory that then will be used by the benchmarks automatically:

kubernetes$ test/integration/logs/benchmark/get-logs.sh
++ dirname test/integration/logs/benchmark/get-logs.sh
+ cd test/integration/logs/benchmark
++ latest_job
++ gsutil cat gs://kubernetes-jenkins/logs/ci-kubernetes-kind-e2e-json-logging/latest-build.txt
+ job=1618864842834186240
+ rm -rf ci-kubernetes-kind-e2e-json-logging
+ mkdir ci-kubernetes-kind-e2e-json-logging
...

This sets up the data directory so that additional test cases are available (BenchmarkEncoding/v3/kind-worker-kubelet/, BenchmarkEncoding/kube-scheduler/, etc.).

To clean up, use

git clean -fx test/integration/logs/benchmark

Analyzing log data

While loading a file, some statistics about it are collected. Those are shown when running with:

go test -v -bench=BenchmarkEncoding/none -run=none  .