From 2bb2425704cc7181c5eb924400b351b3a2d9a592 Mon Sep 17 00:00:00 2001 From: Matthew Heon Date: Wed, 19 Aug 2020 16:15:35 -0400 Subject: Move pod jobs to parallel execution Make Podman pod operations that do not involve starting containers (which needs to be done in a specific order) use the same parallel operation code we use to make `podman stop` on large numbers of containers fast. We were previously stopping containers in a pod serially, which could take up to the timeout (default 15 seconds) for each container - stopping 100 containers that do not respond to SIGTERM would take 25 minutes. To do this, refactor the parallel operation code a bit to remove its dependency on libpod (damn circular import restrictions...) and use parallel functions that just re-use the standard container API operations - maximizes code reuse (previously each pod handler had a separate implementation of the container function it performed). This is a bit of a palate cleanser after fighting CI for two days - nice to be able to return to a land of sanity. Signed-off-by: Matthew Heon --- pkg/parallel/parallel.go | 30 ++++++++++++++++++++++++++++++ 1 file changed, 30 insertions(+) (limited to 'pkg/parallel/parallel.go') diff --git a/pkg/parallel/parallel.go b/pkg/parallel/parallel.go index c9e4da50d..4da7e0f89 100644 --- a/pkg/parallel/parallel.go +++ b/pkg/parallel/parallel.go @@ -1,6 +1,7 @@ package parallel import ( + "context" "sync" "github.com/pkg/errors" @@ -42,3 +43,32 @@ func SetMaxThreads(threads uint) error { func GetMaxThreads() uint { return numThreads } + +// Enqueue adds a single function to the parallel jobs queue. This function will +// be run when an unused thread is available. +// Returns a receive-only error channel that will return the error (if any) from +// the provided function fn when fn has finished executing. The channel will be +// closed after this. +func Enqueue(ctx context.Context, fn func() error) <-chan error { + retChan := make(chan error) + + go func() { + jobControlLock.RLock() + defer jobControlLock.RUnlock() + + defer close(retChan) + + if err := jobControl.Acquire(ctx, 1); err != nil { + retChan <- errors.Wrapf(err, "error acquiring job control semaphore") + return + } + + err := fn() + + jobControl.Release(1) + + retChan <- err + }() + + return retChan +} -- cgit v1.2.3-54-g00ecf