From owner-cvs-all Sun Sep 22 19: 7:19 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 406BD37B401; Sun, 22 Sep 2002 19:07:18 -0700 (PDT) Received: from elvis.mu.org (elvis.mu.org [192.203.228.196]) by mx1.FreeBSD.org (Postfix) with ESMTP id EF59F43E42; Sun, 22 Sep 2002 19:07:17 -0700 (PDT) (envelope-from bright@elvis.mu.org) Received: by elvis.mu.org (Postfix, from userid 1192) id D67CBAE027; Sun, 22 Sep 2002 19:07:17 -0700 (PDT) Date: Sun, 22 Sep 2002 19:07:17 -0700 From: Alfred Perlstein To: Jeff Roberson Cc: Greg 'groggy' Lehey , Jeff Roberson , cvs-committers@FreeBSD.org, cvs-all@FreeBSD.org Subject: Re: cvs commit: src/sys/kern kern_alq.c src/sys/sys alq.h Message-ID: <20020923020717.GC6262@elvis.mu.org> References: <20020923003727.GM21093@wantadilla.lemis.com> <20020922211607.E43954-100000@mail.chesapeake.net> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20020922211607.E43954-100000@mail.chesapeake.net> User-Agent: Mutt/1.4i 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 * Jeff Roberson [020922 18:28] wrote: > 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. Have you thought of running it into a fifo with gzip waiting on the other side? I guess that could sort of cause an infinite loop if you were recording certain process/vnode interaction unless it was batched up somehow. -Alfred To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe cvs-all" in the body of the message