How to tune the garbage collector interval in v8 (--gc_interval is not working)

[WENZHI CUI]

Hi all,

  Sorry to disturb you all but I have a question regarding tuning GC interval in v8.

  I am using Node.js v4.2.1 (with Google v8 v4.5.103) as development platform. I want to study the impact of garbage collector on the overall system performance hence I have to run experiments under different GC settings. In specific, I want to change the interval of GC.

  I tried setting the option "--gc_interval" but it is not working under Release mode (i.e., GC interval is not changed by the option) and will cause a crash under Debug Mode.  So I am wondering if this option is no longer supported or there is something wrong with my setup? 

  Also, if you know other effective ways to tune GC activities (options or source code parameters), that will also help my study. Thanks for your time.

Yours,

Wenzhi Cui

[Yang Guo]

--gc-interval is a debugging flag and not supposed to be used for production.

[WENZHI CUI]

Hi Yang,

  Thanks very much for the reply. 

  I have one follow-up question:

  Is there any way to change GC activities other than setting heap size? I don't mind tweaking the source code if options are not exported. 

Thanks,

Wenzhi Cui

[Yang Guo]

You can run V8 with --expose-gc. You can then call gc() to manually trigger gc. Don't assume this to be officially supported though.