X-Original-To: pgsql-hackers-postgresql.org@localhost.postgresql.org Received: from localhost (unknown [200.46.204.144]) by svr1.postgresql.org (Postfix) with ESMTP id 7E8B952867 for ; Fri, 17 Jun 2005 10:38:19 -0300 (ADT) Received: from svr1.postgresql.org ([200.46.204.71]) by localhost (av.hub.org [200.46.204.144]) (amavisd-new, port 10024) with ESMTP id 26021-02 for ; Fri, 17 Jun 2005 13:38:15 +0000 (GMT) Received: from wproxy.gmail.com (wproxy.gmail.com [64.233.184.205]) by svr1.postgresql.org (Postfix) with ESMTP id 8971E52818 for ; Fri, 17 Jun 2005 10:38:14 -0300 (ADT) Received: by wproxy.gmail.com with SMTP id 68so24486wra for ; Fri, 17 Jun 2005 06:38:18 -0700 (PDT) DomainKey-Signature: a=rsa-sha1; q=dns; c=nofws; s=beta; d=gmail.com; h=received:message-id:date:from:reply-to:to:subject:cc:in-reply-to:mime-version:content-type:content-transfer-encoding:content-disposition:references; b=bA6rXmoQjHw04CfbN+chZMKyR3mxR+ODz/Q6h3K1iFFChCSg7K2qwS2Oolj+vjx+epZCB40ySXvUSFhlNgCh4vxxkYgNEQQiina3Mjx8dQiWkUMvcdmAk+E51nnJIeKyQBoxC/sjQuecEstswsXrlU8b6S5/NIvDxazv1sda7OU= Received: by 10.54.25.5 with SMTP id 5mr1105759wry; Fri, 17 Jun 2005 06:38:18 -0700 (PDT) Received: by 10.54.136.17 with HTTP; Fri, 17 Jun 2005 06:38:18 -0700 (PDT) Message-ID: Date: Fri, 17 Jun 2005 16:38:18 +0300 From: Nicolai Tufar Reply-To: Nicolai Tufar To: josh@agliodbs.com Subject: Re: DTrace Probes? Cc: pgsql-hackers@postgresql.org In-Reply-To: <200506161731.37945.josh@agliodbs.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable Content-Disposition: inline References: <200506161731.37945.josh@agliodbs.com> X-Virus-Scanned: by amavisd-new at hub.org X-Spam-Status: No, hits=0.064 tagged_above=0 required=5 tests=AWL, RCVD_BY_IP X-Spam-Level: X-Archive-Number: 200506/745 X-Sequence-Number: 69226 On 6/17/05, Josh Berkus wrote: > Hey, Folks, >=20 > I need to find someone who's really interesed in working with DTrace. Su= n > has offered to help put DTrace probes into PostgreSQL for advanced > profiling, but need to know where to probe. Anyone? >=20 > I'm afraid that I won't get around to this quickly enough. I played a little with DTrace probes when Solaris 10 just came out. DTrace is useful when you have no source code of application or when you are collecting statistics on a live system. Otherwise it is not much different from gprof apart, maybe, that it can collect statistics about kernel syscalls.=20 Anyways, DTrace is a very powerful yet lightweight tool. Creating a=20 strace program to attach to a running PostgreSQL instance and collect=20 statistics will be a nice thing to do. We may even find some bottlenecks in our code. I can volunteer to do it but I do not have a through understan= ding of PostgreSQL internals.=20 > --Josh Regards,=20 Nicolai