Re: ppoll() stuck on POLLIN while TCP peer is sending

Eric Wong
2013-01-04T00:26:39Z

Eric Wong <normalperson@yhbt.net> wrote:
> I think this requires frequent dirtying/cycling of pages to reproduce.
> (from copying large files around) to interact with compaction.
> I'll see if I can reproduce the issue with read-only FS activity.

Still successfully running the read-only test on my main machine, will
provide another update in a few hours or so if it's still successful
(it usually takes <1 hour to hit).

I also fired up a VM on my laptop (still running v3.7) and was able to
get stuck with only 2 cores and 512M on the VM (x86_64). On the small
VM with little disk space, it doesn't need much dirty data to trigger.
I just did this:

find $45G_NFS_MOUNT -type f -print0 | \
xargs -0 -n1 -P4 sh -c 'cat "$1" >> tmp; > tmp' --

...while running two instances of toosleepy (one got stuck and aborted).