Node should not be able to trigger last resort gc. It can be that recent changes in V8 changed allocation patterns for some large object (array, properties backing store etc) and this now causes last resort GC to happen.
Unfortunately it is impossible to figure out what is going on unless you can somehow get a back trace from inside CollectAllAvailableGarbage. -- Vyacheslav Egorov On Mon, Nov 5, 2012 at 7:08 AM, Joran Dirk Greef <[email protected]> wrote: > In practice it's working perfectly now. I rolled Node from v0.8 back to v0.6 > and the false positive allocation errors are no longer happening. There's no > more "last resort gc". Load has dropped from 100% to 1%. The gc trace looks > normal now. I assumed the GC errors were due to the different version of V8 > bundled with Node. Perhaps it's something in Node triggering full GC > repetitively? Would Node trigger GC by itself? > > > On Monday, November 5, 2012 4:53:59 PM UTC+2, Vyacheslav Egorov wrote: >> >> > Recent GC changes are unable to handle millions of long-lived entities. >> > V8 3.6.6.25 GC works perfectly. >> >> Contrary to what you might think worst pause time for V8 3.6.x and V8 >> 3.7 - 3.15 should be roughly the same. V8 3.7 will also do 7 GCs in a >> row as a last resort. >> >> However in 3.6 if you hit a full collection it will always pause your >> app for much longer then a incremental collector of 3.7 and later >> would (given that everything is tweaked correctly). >> >> -- >> Vyacheslav Egorov >> >> >> On Mon, Nov 5, 2012 at 1:28 AM, Joran Dirk Greef <[email protected]> >> wrote: >> > Recent GC changes in V8 are wreaking havoc with a production app. GC >> > traces >> > are showing pauses of over 22 seconds. Recent GC changes are unable to >> > handle millions of long-lived entities. >> > >> > V8 3.6.6.25 GC works perfectly. >> > >> > The one problem now is getting V8 3.6.6.25 to allow max-old-space-size >> > greater than 1900 MB on Ubuntu. >> > >> > Is there any way to run V8 3.6.6.25 with max-old-space-size greater than >> > 1900 MB? >> > >> > Or is there a slightly newer version than 3.6.6.25 which allows bigger >> > heaps >> > but without all the new GC work? >> > >> > Your help would be much appreciated. >> > >> > -- >> > v8-users mailing list >> > [email protected] >> > http://groups.google.com/group/v8-users > > -- > v8-users mailing list > [email protected] > http://groups.google.com/group/v8-users -- v8-users mailing list [email protected] http://groups.google.com/group/v8-users
