diff options
| author | Richard van der Hoff <1389908+richvdh@users.noreply.github.com> | 2024-03-13 17:21:37 +0000 |
|---|---|---|
| committer | GitHub <noreply@github.com> | 2024-03-13 17:21:37 +0000 |
| commit | 92f20696273ca88c24d1dcdd738bd0f1d4be9e61 (patch) | |
| tree | 3266b93e37633af52e2916ce1648a4ce882c7490 | |
| parent | Bump ruff from 0.1.14 to 0.3.2 (#16994) (diff) | |
| download | synapse-92f20696273ca88c24d1dcdd738bd0f1d4be9e61.tar.xz | |
Multi-worker-docker-container: disable log buffering (#16919)
Background: we have a `matrixdotorg/synapse-workers` docker image, which is intended for running multiple workers within the same container. That image includes a `prefix-log` script which, for each line printed to stdout or stderr by one of the processes, prepends the name of the process. This commit disables buffering in that script, so that lines are logged quickly after they are printed. This makes it much easier to understand the output, since they then come out in a natural order.
| -rw-r--r-- | changelog.d/16919.misc | 1 | ||||
| -rwxr-xr-x | docker/prefix-log | 7 |
2 files changed, 6 insertions, 2 deletions
diff --git a/changelog.d/16919.misc b/changelog.d/16919.misc new file mode 100644 index 0000000000..2c76f25379 --- /dev/null +++ b/changelog.d/16919.misc @@ -0,0 +1 @@ +Multi-worker-docker-container: disable log buffering. diff --git a/docker/prefix-log b/docker/prefix-log index 0e26a4f19d..32dddbbfd4 100755 --- a/docker/prefix-log +++ b/docker/prefix-log @@ -7,6 +7,9 @@ # prefix-log command [args...] # -exec 1> >(awk '{print "'"${SUPERVISOR_PROCESS_NAME}"' | "$0}' >&1) -exec 2> >(awk '{print "'"${SUPERVISOR_PROCESS_NAME}"' | "$0}' >&2) +# '-W interactive' is a `mawk` extension which disables buffering on stdout and sets line-buffered reads on +# stdin. The effect is that the output is flushed after each line, rather than being batched, which helps reduce +# confusion due to to interleaving of the different processes. +exec 1> >(awk -W interactive '{print "'"${SUPERVISOR_PROCESS_NAME}"' | "$0 }' >&1) +exec 2> >(awk -W interactive '{print "'"${SUPERVISOR_PROCESS_NAME}"' | "$0 }' >&2) exec "$@" |