diff --git a/resource/image.go b/resource/image.go index d9a1dd47d..fc79cbef5 100644 --- a/resource/image.go +++ b/resource/image.go @@ -212,6 +212,15 @@ func (i *Image) isJPEG() bool { return strings.HasSuffix(name, ".jpg") || strings.HasSuffix(name, ".jpeg") } +// Serialize image processing. The imaging library spins up its own set of Go routines, +// so there is not much to gain from adding more load to the mix. That +// can even have negative effect in low resource scenarios. +// Note that this only effects the non-cached scenario. Once the processed +// image is written to disk, everything is fast, fast fast. +const imageProcWorkers = 1 + +var imageProcSem = make(chan bool, imageProcWorkers) + func (i *Image) doWithImageConfig(action, spec string, f func(src image.Image, conf imageConfig) (image.Image, error)) (*Image, error) { conf, err := parseImageConfig(spec) if err != nil { @@ -237,6 +246,11 @@ func (i *Image) doWithImageConfig(action, spec string, f func(src image.Image, c } return i.spec.imageCache.getOrCreate(i, conf, func(resourceCacheFilename string) (*Image, error) { + imageProcSem <- true + defer func() { + <-imageProcSem + }() + ci := i.clone() errOp := action