From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id ; Wed, 31 Jan 2001 13:34:06 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Wed, 31 Jan 2001 13:33:56 -0500 Received: from md.aacisd.com ([64.23.207.34]:10001 "HELO md.aacisd.com") by vger.kernel.org with SMTP id ; Wed, 31 Jan 2001 13:33:44 -0500 Message-ID: <8FED3D71D1D2D411992A009027711D671880@md> From: Nathan Black To: "'bert hubert'" Cc: linux-kernel@vger.kernel.org Subject: RE: drive/block device write scheduling, buffer flushing? Date: Wed, 31 Jan 2001 13:29:05 -0500 MIME-Version: 1.0 X-Mailer: Internet Mail Service (5.5.2653.19) Content-Type: text/plain; charset="iso-8859-1" Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org That is what I wanted to do...Write directly to the disk. But the kernel(2.4.1) is caching the io... -----Original Message----- From: bert hubert [mailto:ahu@ds9a.nl] Sent: Wednesday, January 31, 2001 12:51 PM To: Nathan Black Cc: linux-kernel@vger.kernel.org Subject: Re: drive/block device write scheduling, buffer flushing? On Wed, Jan 31, 2001 at 11:52:25AM -0500, Nathan Black wrote: > I was wondering if there is a way to make the kernel write to disk faster. > I need to maintain a 10 MB /sec write rate to a 10K scsi disk in a computer, > but it caches and doesn't start writing to disk until I hit about 700 MB. At > that point, it pauses(presumably while the kernel is flushing some of the > buffers) and I will have missed data that I am trying to capture. try opening with O_SYNC, or call fsync() every once in a while. Otherwise, this sounds like an application for a raw device, whereby you can write directly to the disk, with no caching in between. Regards, bert -- PowerDNS Versatile DNS Services Trilab The Technology People 'SYN! .. SYN|ACK! .. ACK!' - the mating call of the internet - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org Please read the FAQ at http://www.tux.org/lkml/