Re: [take13 1/3] kevent: Core files.

Andrew Morton
2006-08-25T07:13:52Z

On Fri, 25 Aug 2006 00:01:06 -0700 (PDT)
David Miller <davem@davemloft.net> wrote:

> From: Andrew Morton <akpm@osdl.org>
> Date: Thu, 24 Aug 2006 23:20:24 -0700
>
> > On Fri, 25 Aug 2006 09:48:15 +0400
> > Evgeniy Polyakov <johnpol@2ka.mipt.ru> wrote:
> >
> > > kmalloc is really slow actually - it always shows somewhere on top
> > > in profiles and brings noticeble overhead
> >
> > It shouldn't. Please describe the workload and send the profiles.
>
> Not that I can account for the problem in this specific case, in my
> experience cutting down kmalloc() calls matters a _lot_ performance
> wise.
>
> For example, this is why we allocate TCP sockets as one huge blob
> instead of 3 seperate allocations (generic socket, IP socket, TCP
> socket).
>
> In fact, one of the remaining performance issues in IPSEC rule
> creation is that we allocate seperately hunks of memory for the rule's
> encryption state, the optional hash algorithm state, etc.

Part of that will be cache sharing between the three structs though.