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

Bron Gondwana
2009-01-28T04:55:45Z

On Tue, Jan 27, 2009 at 08:14:36PM -0800, Davide Libenzi wrote:
> On Tue, 27 Jan 2009, Ray Lee wrote:
> > Userspace is not broken here, and the whole idea of a -stable series
> > is that administrators can upgrade to them without having to worry
> > about things getting broken or making specific configuration changes
> > by point release.
>
> The reason Greg took it, was that in a multiuser systems, that's a DoS
> EZ-PZ Lemon Squeezie.

Ok - we're at an impasse here.

You know the code a whole lot better than me.

Is there anything you can think of that will allow us to block the DOS
without breaking every medium to heavily loaded postfix and apache site
out there.

Somthing that doesn't require the administrators of every single
machine in one or the other class to tune their configurations?

Brong ( we expect you to know how to tune epoll, we don't expect every
apache and postfix administrator to know to tune a brand new
setting that just appeared in the last point release - especially
since most of them probably have no idea how many epoll watches
their software creates as a single user, and have never needed
to think about it before)