From owner-freebsd-fs Wed Aug 22 0:34:30 2001 Delivered-To: freebsd-fs@freebsd.org Received: from snipe.mail.pas.earthlink.net (snipe.mail.pas.earthlink.net [207.217.120.62]) by hub.freebsd.org (Postfix) with ESMTP id 3B19D37B40B for ; Wed, 22 Aug 2001 00:34:28 -0700 (PDT) (envelope-from tlambert2@mindspring.com) Received: from mindspring.com (dialup-209.245.135.228.Dial1.SanJose1.Level3.net [209.245.135.228]) by snipe.mail.pas.earthlink.net (8.11.5/8.9.3) with ESMTP id f7M7YQh15885; Wed, 22 Aug 2001 00:34:26 -0700 (PDT) Message-ID: <3B8360AC.559D205D@mindspring.com> Date: Wed, 22 Aug 2001 00:35:08 -0700 From: Terry Lambert Reply-To: tlambert2@mindspring.com X-Mailer: Mozilla 4.7 [en]C-CCK-MCD {Sony} (Win98; U) X-Accept-Language: en MIME-Version: 1.0 To: Jeff Behl Cc: freebsd-fs@freebsd.org Subject: Re: syncer delay? References: <0307F3737A2AD511A42200D0B7A071919A409C@dopey.corp.expertcity.com> Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Sender: owner-freebsd-fs@FreeBSD.ORG Precedence: bulk List-ID: List-Archive: (Web Archive) List-Help: (List Instructions) List-Subscribe: List-Unsubscribe: X-Loop: FreeBSD.org Jeff Behl wrote: > > thanks for info. just to clarify a few things... > > Its 'logging' is actually writing binary data to a file, of which there is > one file per session/open socket. The number of sessions isn't that large, > averaging around 20, and the machine is dedicated to this app only. The > only reads should be from the network. This help narrow down the issue? Yes; you have 20 contenders fighting for your serialized access to your IDE drive. If you don't need the data committed to stable storage for some reason that you aren't stating, then you would probably be much better off caching it, and going to a sparse map on page or FS block boundaries so that the FS doesn't have to do the extra read-before-write to handle the writes. > We'll see if an explicit fsync() helps; thanks. It probably won't help as much as choosing your data carefully. Also, if you hhave a big stable storage requirement, you might want to consider writing your state information/log to a raw disk device on 512b boundaries to make things a lot easier on your I/O overhead. -- Terry To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-fs" in the body of the message