foreach + doMC not fully parallel?

I suggest you try:

1) run your R code from R directly
2) test similar code without IO from hard disk
3) If combining 1) and 2) still give you the similar result, could you
provide a simple reproducible code? Especially the part you mentioned
as "lots of computation".

Xie Chao

1 & 2 I had already tried.

I did a reboot and %dopar% started working fully again. I then did
suspend/resume and the problem came back. i rarely reboot and use
suspend/resume all the time (running on my laptop). Most likely it's a
kernel problem. I will have to investigate a little more thoroughly, but
it's obvious now that this is not an R problem.

Thanks everyone here who gave advice! Seems time to ask the kernel folks
at Ubuntu. Definitely there's a bug here (maybe something to do with
SCI_EN--I'll have to troubleshoot).

-Brian