From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 24662 invoked by alias); 15 Dec 2009 03:56:47 -0000 Received: (qmail 24652 invoked by uid 22791); 15 Dec 2009 03:56:46 -0000 X-SWARE-Spam-Status: No, hits=-1.7 required=5.0 tests=AWL,BAYES_00,SARE_MSGID_LONG40,SPF_PASS X-Spam-Check-By: sourceware.org Received: from mail-pz0-f189.google.com (HELO mail-pz0-f189.google.com) (209.85.222.189) by sourceware.org (qpsmtpd/0.43rc1) with ESMTP; Tue, 15 Dec 2009 03:56:41 +0000 Received: by pzk27 with SMTP id 27so2761218pzk.12 for ; Mon, 14 Dec 2009 19:56:40 -0800 (PST) MIME-Version: 1.0 Received: by 10.142.119.24 with SMTP id r24mr815245wfc.291.1260849399969; Mon, 14 Dec 2009 19:56:39 -0800 (PST) In-Reply-To: <5e81cb500912141840s389859c2r9c56dd8800adb731@mail.gmail.com> References: <5e81cb500912040734u5ce67afdpd6a2d0e63173f908@mail.gmail.com> <5e81cb500912140518r2ad3f2fdrd0dd5a546e6d8a33@mail.gmail.com> <5e81cb500912141840s389859c2r9c56dd8800adb731@mail.gmail.com> From: Hui Zhu Date: Tue, 15 Dec 2009 03:56:00 -0000 Message-ID: Subject: Re: UndoDB's performance To: Sean Chen Cc: gdb@sourceware.org Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: quoted-printable X-IsSubscribed: yes Mailing-List: contact gdb-help@sourceware.org; run by ezmlm Precedence: bulk List-Id: List-Subscribe: List-Archive: List-Post: List-Help: , Sender: gdb-owner@sourceware.org X-SW-Source: 2009-12/txt/msg00091.txt.bz2 I did some test but its speed close to prec. Some others was better. Maybe it have some special performance technology for some code. Hui On Tue, Dec 15, 2009 at 10:40, Sean Chen wrote: > On Mon, Dec 14, 2009 at 11:07 PM, Hui Zhu wrote: >> Try undodb. >> >> On Mon, Dec 14, 2009 at 21:18, Sean Chen wrote: >>> On Mon, Dec 14, 2009 at 7:14 PM, Hui Zhu wrote: >>>> gdb-7 reverse debugging accelerator. >>>> Regular gdb-7 reverse runs apps =A0 =A0 =A0 =A0 =A040,000x =A0 =A0 =A0= =A0 =A0 =A0 =A0 =A0slower >>>> UndoDB+gdb-7 reverse runs apps =A0 =A0 =A0 =A0 =A0 1.7x =A0 =A0 =A0 = =A0 =A0 =A0slower! >>>> >>>> >>>> Are you really do some try? >>>> I suggest you do some test on it. =A0:) >>>> >>>> Thanks, >>>> Hui >>>> >>>> On Fri, Dec 4, 2009 at 23:34, Sean Chen wrot= e: >>>>> On UndoDb=92s website, I saw the following ad. >>>>> >>>>> Regular gdb-7 reverse runs apps 40,000x slower >>>>> UndoDB+gdb-7 reverse runs apps 1.7x slower! >>>>> >>>>> In my experiment, gdb-7 reverse does run apps more than 20,000x >>>>> slower. How does UndoDB improve the performance so much without a >>>>> simulator and without record? Below is its self-introduction on the >>>>> website. UndoDB's "snapshot-and-replay" technique stores periodic >>>>> copy-on-write snapshots of the application and only non-deterministic >>>>> inputs (system calls, thread-switches, shared memory reads, etc). >>>>> >>>>> Are there any obvious disadvantages in UndoDB? I tried to search >>>>> UndoDB in the archive of the mailing list, however, little discussion >>>>> is found. >>>>> >>>>> -- >>>>> Best Regards, >>>>> Sean Chen >>>>> >>>> >>> >>> That=92s UndoDB=92s ad on its website. >>> >>> In my experiment, gdb-7 reverse runs apps about 22,000x slower. >>> >>> -- >>> Best Regards, >>> Sean Chen >>> >> > > I also tried UndoDB, and it is really fast. So I am sure they are > using different strategy. > > -- > Best Regards, > Sean Chen >