ref: 3a3badfd1d4b1d4c9863ecaf029512d36136fa0f
parent: df021317a964a482cd1cd579de5a12d50faf0d08
author: Bjørn Erik Pedersen <[email protected]>
date: Fri Oct 26 09:45:51 EDT 2018
resource: Serialize image processing Fixes #5220
--- a/resource/image.go
+++ b/resource/image.go
@@ -212,6 +212,15 @@
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 @@
}
return i.spec.imageCache.getOrCreate(i, conf, func(resourceCacheFilename string) (*Image, error) {+ imageProcSem <- true
+ defer func() {+ <-imageProcSem
+ }()
+
ci := i.clone()
errOp := action