From owner-freebsd-questions Fri Oct 12 10:55:52 2001 Delivered-To: freebsd-questions@freebsd.org Received: from navgwout.symantec.com (navgwout.symantec.com [198.6.49.12]) by hub.freebsd.org (Postfix) with ESMTP id CD86237B403 for ; Fri, 12 Oct 2001 10:55:47 -0700 (PDT) Received: from navgwout.symantec.com (navgwout [198.6.49.12]) by navgwout.symantec.com (8.9.3+Sun/8.9.3) with SMTP id KAA24230 for ; Fri, 12 Oct 2001 10:55:47 -0700 (PDT) Received: from mailer.symantec.com ([198.6.49.176]) by navgwout.symantec.com (NAVGW 2.5.1.13) with SMTP id M2001101210554611124 for ; Fri, 12 Oct 2001 10:55:46 -0700 Received: from uscu-smtp02.symantec.com (uscu-smtp02.symantec.com [155.64.74.114]) by mailer.symantec.com (8.9.3+Sun/8.9.3) with ESMTP id KAA24097 for ; Fri, 12 Oct 2001 10:55:41 -0700 (PDT) Subject: I/O Problems To: freebsd-questions@freebsd.org X-Mailer: Lotus Notes Release 5.0.8 June 18, 2001 Message-ID: From: "Jay Rossiter" Date: Fri, 12 Oct 2001 10:53:02 -0700 X-MIMETrack: Serialize by Router on USCU-SMTP02/SYMSMTP(Release 5.0.8 |June 18, 2001) at 10/12/2001 10:48:36 AM MIME-Version: 1.0 Content-type: text/plain; charset=us-ascii Sender: owner-freebsd-questions@FreeBSD.ORG Precedence: bulk List-ID: List-Archive: (Web Archive) List-Help: (List Instructions) List-Subscribe: List-Unsubscribe: X-Loop: FreeBSD.ORG Ok.. got no response at all last time I asked, but... There appear to be a lot of changes that went into the filesystem and I/O code between 4.3 and 4.4. A little over a week ago I upgraded my 4.3 box to 4.4-STABLE and immediately I started having I/O slowdown. I do development and QA on a program that is very I/O bound, but the changes between 4.3 and 4.4 aren't enough that I can ignore them. A few statistics: BSD, P4 1.4GHz, ATA100 drives - Normal test run on 4.3 was taking 3 hours. - Normal test run on 4.4 is taking 15-16 hours. P3-800, ATA66 drives, SuSE Linux 7.1: - Normal test run takes 4-4.5 hours. UltraSparc 10, Solaris 8, ATA66 drives: - Normal test run takes 6 hours. As you can see, this jump was just phenomenal. I can run these tests on a custom 'ramdrive' and the test run takes 1.5 hours on BSD. ~4 on Solaris, ~2.5 on Linux. Even the RS/6000 I test AIX 4.3 with doesn't take this long, though I don't have statistics for it. It appears that the app gets stuck switching between the getblk and biowr states in top and ps, and very rarely does it take more than 5% of the CPU. On all other OS's, and even on 4.3, this app was pegging the CPU while it did its work. Basically.. this all comes down to "What the hell is going on here?!" and "Are there plans to fix it and did anyone even know there was a problem?" --- Jay Rossiter 503-614-7917 QA Engineer, Test Lead Symantec Corp. To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-questions" in the body of the message