From mboxrd@z Thu Jan 1 00:00:00 1970 From: Andrew Morton Subject: Re: [take13 1/3] kevent: Core files. Date: Fri, 25 Aug 2006 00:13:14 -0700 Message-ID: <20060825001314.b320b10a.akpm@osdl.org> References: <20060824200322.GA19533@infradead.org> <20060825054815.GC16504@2ka.mipt.ru> <20060824232024.0d230823.akpm@osdl.org> <20060825.000106.30184424.davem@davemloft.net> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Cc: johnpol@2ka.mipt.ru, hch@infradead.org, linux-kernel@vger.kernel.org, drepper@redhat.com, netdev@vger.kernel.org, zach.brown@oracle.com Return-path: Received: from smtp.osdl.org ([65.172.181.4]:15532 "EHLO smtp.osdl.org") by vger.kernel.org with ESMTP id S1750821AbWHYHNv (ORCPT ); Fri, 25 Aug 2006 03:13:51 -0400 To: David Miller In-Reply-To: <20060825.000106.30184424.davem@davemloft.net> Sender: netdev-owner@vger.kernel.org List-Id: netdev.vger.kernel.org On Fri, 25 Aug 2006 00:01:06 -0700 (PDT) David Miller wrote: > From: Andrew Morton > Date: Thu, 24 Aug 2006 23:20:24 -0700 > > > On Fri, 25 Aug 2006 09:48:15 +0400 > > Evgeniy Polyakov 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.