From owner-cvs-all Sun Sep 22 18:28:31 2002 Delivered-To: cvs-all@freebsd.org Received: from mx1.FreeBSD.org (mx1.FreeBSD.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id EDC6037B401; Sun, 22 Sep 2002 18:28:29 -0700 (PDT) Received: from mail.chesapeake.net (chesapeake.net [205.130.220.14]) by mx1.FreeBSD.org (Postfix) with ESMTP id 0CB9443E3B; Sun, 22 Sep 2002 18:28:28 -0700 (PDT) (envelope-from jroberson@chesapeake.net) Received: from localhost (jroberson@localhost) by mail.chesapeake.net (8.11.6/8.11.6) with ESMTP id g8N1SRN89154; Sun, 22 Sep 2002 21:28:27 -0400 (EDT) (envelope-from jroberson@chesapeake.net) Date: Sun, 22 Sep 2002 21:28:27 -0400 (EDT) From: Jeff Roberson To: "Greg 'groggy' Lehey" Cc: Jeff Roberson , , Subject: Re: cvs commit: src/sys/kern kern_alq.c src/sys/sys alq.h In-Reply-To: <20020923003727.GM21093@wantadilla.lemis.com> Message-ID: <20020922211607.E43954-100000@mail.chesapeake.net> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-cvs-all@FreeBSD.ORG Precedence: bulk List-ID: List-Archive: (Web Archive) List-Help: (List Instructions) List-Subscribe: List-Unsubscribe: X-Loop: FreeBSD.ORG On Mon, 23 Sep 2002, Greg 'groggy' Lehey wrote: > On Sunday, 22 September 2002 at 0:11:14 -0700, Jeff Roberson wrote: > > jeff 2002/09/22 00:11:14 PDT > > > > Added files: > > sys/kern kern_alq.c > > sys/sys alq.h > > Log: > > - Add an asynchronous fixed length record logging mechanism called > > ALQ (Asynch. Logging Queues). ALQ supports many seperate queues with > > different record and buffer sizes. It opens and logs to any vnode so > > it can be used with character devices as well as regular files. > > What's the purpose of this functionality? > > Greg > -- > See complete headers for address and phone numbers > Well, for now it's only used by ktr. I believe that it could be applied to other areas as well. In general I need it for recording long term events such as disk or network activity for post analysis. It could also be useful for diagnosing problems with VFS by logging all VOPs via ktr. It could also be used for logging binary kernel data w/o going through ktr. Any subsystem could create a queue and record it's actions over a long period. ktrace could be implemented on top of an ALQ, although this would be slightly more difficult since it does not use fixed length records. Jeff To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe cvs-all" in the body of the message