gostatic
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piranha
too many open files
I was trying to build your site but when serving the pages I get
$ make w
gostatic -w config
Rendering 0 changed pages of 292 total
Starting server at *:8000...
2016/07/04 22:37:34 http: Accept error: accept tcp [::]:8000: accept: too many open files; retrying in 5ms
2016/07/04 22:37:34 http: Accept error: accept tcp [::]:8000: accept: too many open files; retrying in 10ms
Building it and running python -m SimpleHTTPServer 8000 instead works fine though.
Running ulimit -S -n 4096 will fix that. gostatic opens all files and it takes time to GC them it seems, so it can blow with such an error.
OK, let's rephrase that then: why does it open all files and keep them open?
I think first part is obvious, but second one is not. :) I did look at why it opens them IIRC, but I didn't action on it. Not sure why it keeps them open though, that needs to be researched again it seems. :)
I think first part is obvious, but second one is not. :)
true :)
that needs to be researched again it seems.
care to re-open then?
Sure! :)) If you want to research/fix that, I would really appreciate it! If not, I guess I'll look at that sometime, but not sure when - a bit too busy lately with work and real-life stuff.
Had a look at the FAQ for fsnotify (which is imported by lib/watch.go)
How many files can be watched at once?
There are OS-specific limits as to how many watches can be created:
Linux: /proc/sys/fs/inotify/max_user_watches contains the limit, reaching this limit results in a "no space left on device" error. BSD / OSX: sysctl variables "kern.maxfiles" and "kern.maxfilesperproc", reaching these limits results in a "too many open files" error.
As long as you're watching them, the files have to be open. It's easiest to increase the limit.
Alternatively you could use a "polling" approach which is way slower, but will work for any amount of files.
Well, that statement isn't true for all OS. On macOS it would be great to use FSEvents.
https://github.com/emcrisostomo/fswatch
But it sounds like there is a progress in supporting that with fsnotify.
https://github.com/golang/go/issues/4068