Re: frequent lockups in 3.18rc4

From: Linus Torvalds
Date: Fri Dec 12 2014 - 19:44:55 EST

On Fri, Dec 12, 2014 at 4:34 PM, Sasha Levin <sasha.levin@xxxxxxxxxx> wrote:
> Right, it's virtio-9p. However, virtio-9p acts merely as a proxy to an underlying
> tmpfs - so while it's slow, I don't think it's way slower than the average disk
> backed ext4.

I was thinking more in the sense of "how much of the trouble is about
something like tmpfs eating tons of memory when trinity starts doing
random system calls on those files".

I was also thinking that some of it might be filesystem-specific. We
already *did* see one trace where it was in the loop getting virtio
channel data. Maybe it's actually possible to overwhelm the 9p
filesystem exactly because the backing store is tmpfs, and basically
have a CPU 100% busy handling ring events from the virtual

But I'm just flailing..

To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at
Please read the FAQ at