On Wed, 01 Feb 2006 15:42:39 -0800 (PST) "David S. Miller" <[EMAIL PROTECTED]> wrote:
> From: Andi Kleen <[EMAIL PROTECTED]> > Date: Wed, 1 Feb 2006 23:55:11 +0100 > > > On Wednesday 01 February 2006 21:26, Jeff Garzik wrote: > > > Andi Kleen wrote: > > > > But I don't think Van's design is supposed to be exposed to user space. > > > > > > It is supposed to be exposed to userspace AFAICS. > > > > Then it's likely insecure and root only, unless he knows some magic > > that we don't. > > > > I hope it's not just PF_PACKET mmap rings with a user space TCP library. > > Yes, that's it. > > If the user screws up the TCP connection and corrupts his data why > should the kernel care? > > > I mean the Linux implementation is in the kernel, but in user context. > > Right, but prequeue doesn't go nearly far enough. We still do up to 5 > demuxes on the input path (protocol, route, IPSEC, netfilter, socket) > plus the queueing at the softint layer. That's rediculious and we've > always understood this, and Van has presented a way to kill this stuff > off. > > But even if you don't like the userspace stuff, we don't necessarily > have to go there, we can just demux directly to sockets in the kernel > TCP stack and then revisit the userspace idea before committing to it. > The bigger problem I see is scalability. All those mmap rings have to be pinned in memory to be useful. It's fine for a single smart application per server environment, but in real world with many dumb thread monster applications on a single server it will be really hard to get working. -- Stephen Hemminger <[EMAIL PROTECTED]> OSDL http://developer.osdl.org/~shemminger - To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html
