From owner-freebsd-hackers@FreeBSD.ORG Mon Nov 12 08:06:57 2007 Return-Path: Delivered-To: freebsd-hackers@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 2AFF316A421 for ; Mon, 12 Nov 2007 08:06:57 +0000 (UTC) (envelope-from adrian.chadd@gmail.com) Received: from py-out-1112.google.com (py-out-1112.google.com [64.233.166.177]) by mx1.freebsd.org (Postfix) with ESMTP id D4BB313C49D for ; Mon, 12 Nov 2007 08:06:56 +0000 (UTC) (envelope-from adrian.chadd@gmail.com) Received: by py-out-1112.google.com with SMTP id u77so1148841pyb for ; Mon, 12 Nov 2007 00:06:45 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=beta; h=domainkey-signature:received:received:message-id:date:from:sender:to:subject:cc:in-reply-to:mime-version:content-type:content-transfer-encoding:content-disposition:references:x-google-sender-auth; bh=Uq81snLLleKiPbbXKpJoaHaBzEFdzmm5FGWpQPuJW38=; b=uEHGqXRtkmX+nwSonKF364zU0mVwqyfHefXaJGN39U55Edrit0Hr5aI9SqcJuW2C1yDSh5v2GN0Ele8Hh9L8YERDBHmf/GrsPtQsO2tO6qOBkor4FocGRD311gCspZWi7+/wn5jQeHKpZ3Kv6nGZEV7RQGF75Ae3KAbLtWh4zqY= DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=beta; h=received:message-id:date:from:sender:to:subject:cc:in-reply-to:mime-version:content-type:content-transfer-encoding:content-disposition:references:x-google-sender-auth; b=i5C6EVojgAHYv/b816YnBov4PfXdRrwEbsEUEbSCQmW7reJ2zIbo7j+OexZLq7Whrofoz1VG6571RMy16DK1DbRiHFCZuF4r61wZoZRvqJjo3HcTPUAMTbpRLOEn3qeHRcXZJtnHDHpTmXMrMl1SDk7p9xiM6dbcNcPlRAclxo8= Received: by 10.65.240.17 with SMTP id s17mr13150017qbr.1194854805510; Mon, 12 Nov 2007 00:06:45 -0800 (PST) Received: by 10.65.237.12 with HTTP; Mon, 12 Nov 2007 00:06:45 -0800 (PST) Message-ID: Date: Mon, 12 Nov 2007 17:06:45 +0900 From: "Adrian Chadd" Sender: adrian.chadd@gmail.com To: "Randall Hyde" In-Reply-To: <002701c8248b$9c2b8110$6302a8c0@pentiv> MIME-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Content-Disposition: inline References: <000701c82253$b3a8c030$6302a8c0@pentiv> <20071108225238.GB22005@dan.emsphone.com> <4734061D.9000606@freebsd.org> <002701c8248b$9c2b8110$6302a8c0@pentiv> X-Google-Sender-Auth: 58a54949dcb1bfa4 Cc: freebsd-hackers@freebsd.org Subject: Re: Some FreeBSD performance Issues X-BeenThere: freebsd-hackers@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Technical Discussions relating to FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 12 Nov 2007 08:06:57 -0000 On 12/11/2007, Randall Hyde wrote: > At this point I'm not sure why FreeBSD's API call is so slow (btw, it's not > the system call that's responsible, if I make several additional API calls > on each read, e.g., doing lseeks, this has only a marginal impact on > performance). But it's pretty clear that if I expect reasonable performance > in my own library I'm going to have to do the same thing that glib does and > switch over to buffered I/O. Pain in the butt, but there's nothing else to > do at this point. Why give up at this point? Why not actually do some pmcstat profiling to see where all the CPU time is going? Adrian -- Adrian Chadd - adrian@freebsd.org