Re: [PATCH 1/3] epoll: increase default max_user_instances to 1024

From: Davide Libenzi
Date: Wed Jan 28 2009 - 11:53:17 EST


On Wed, 28 Jan 2009, Vegard Nossum wrote:

> On Wed, Jan 28, 2009 at 6:32 AM, Bron Gondwana <brong@xxxxxxxxxxx> wrote:
> > That's clearly not happening here - so it seems that maybe our "happy
> > medium" is actually in closer inspection of what's going on rather than
> > a blanket low N to keep N^2 down.
>
> Mh, could another solution to this all be to limit the number times
> you can add a single epoll descriptor to another descriptor's set?

In the example that was posted, a single fd was added a single time inside
the other 1000+ fds. Epoll already has detection for too long chains and
closed loops, but you can't put those in the fast path. And epoll_ctl() is
one of those.


- Davide


--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/