From owner-freebsd-current@FreeBSD.ORG Thu Apr 2 19:18:38 2009 Return-Path: Delivered-To: freebsd-current@FreeBSD.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 54E1B106567C for ; Thu, 2 Apr 2009 19:18:38 +0000 (UTC) (envelope-from julian@elischer.org) Received: from outF.internet-mail-service.net (outf.internet-mail-service.net [216.240.47.229]) by mx1.freebsd.org (Postfix) with ESMTP id E7D2B8FC23 for ; Thu, 2 Apr 2009 19:18:37 +0000 (UTC) (envelope-from julian@elischer.org) Received: from idiom.com (mx0.idiom.com [216.240.32.160]) by out.internet-mail-service.net (Postfix) with ESMTP id 1871E1F673; Thu, 2 Apr 2009 12:18:38 -0700 (PDT) X-Client-Authorized: MaGic Cook1e X-Client-Authorized: MaGic Cook1e X-Client-Authorized: MaGic Cook1e X-Client-Authorized: MaGic Cook1e X-Client-Authorized: MaGic Cook1e X-Client-Authorized: MaGic Cook1e X-Client-Authorized: MaGic Cook1e Received: from julian-mac.elischer.org (home.elischer.org [216.240.48.38]) by idiom.com (Postfix) with ESMTP id 0679F2D6116; Thu, 2 Apr 2009 12:18:33 -0700 (PDT) Message-ID: <49D50FA6.1020202@elischer.org> Date: Thu, 02 Apr 2009 12:19:02 -0700 From: Julian Elischer User-Agent: Thunderbird 2.0.0.21 (Macintosh/20090302) MIME-Version: 1.0 To: Sergey Babkin References: <6547642.196222.1238698084570.JavaMail.root@vms062.mailsrvcs.net> In-Reply-To: <6547642.196222.1238698084570.JavaMail.root@vms062.mailsrvcs.net> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Cc: sobomax@FreeBSD.org, peterjeremy@optushome.com.au, freebsd-current@FreeBSD.org, davidxu@FreeBSD.org, freebsd-hackers@FreeBSD.org, prashant.vaibhav@gmail.com Subject: Re: Improving the kernel/i386 timecounter performance (GSoC proposal) X-BeenThere: freebsd-current@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Discussions about the use of FreeBSD-current List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 02 Apr 2009 19:18:38 -0000 Hey Sergey, whatever you are using for a mail client SUCKS real bad at the moment.. it's really messing up your outgoing mails.. note the mail below.... Sergey Babkin wrote: > Apr 2, 2009 01:03:48 AM, [1]peterjeremy@optushome.com.au wrot= : > >On 2009-Mar-30 18:45:30 -0700, Maxim Sobolev <[2]sobomax@freebsd.org> > wrote: > >>You don't really need to =o it on every execve() unconditionally. > It > >>could be done on de=and in libc, so that only when thread pass > certain > >>threshold, =he "common page optimization code" kicks in and does > its > >>open/=map/etc magic. Otherwise, "normal" syscall is performed. > > > >Th=s "optimisation" is premature. First step is to implement an > >appro=ch that always maps (or whatever) the data and then gather > some > >inf=rmation about its overheads in the real world. If they are > deemed > >=xcessive, only then do we start looking at how to improve things. > >A=d IMO, the first step would be to lazily map the page - so it's > not > >=mapped by default but mapped the first time any of the information > in > &=t;it is used. > Does it make sense to even bother with lazy mapping? =fter all, this > is a very minor > activity compared to mapping and linking=he dynamic libc. I think > the overhead > won't be even noticeable. If you=lready map 200 pages, adding one > more should not > make much difference. -SB > > References > > 1. 3D"mailto:peterjeremy@optushome.com.au" > 2. file://localhost/tmp/3D"m_______________________________________________ > freebsd-current@freebsd.org mailing list > http://lists.freebsd.org/mailman/listinfo/freebsd-current > To unsubscribe, send any mail to "freebsd-current-unsubscribe@freebsd.org"