From owner-freebsd-questions Thu Oct 14 7:40: 5 1999 Delivered-To: freebsd-questions@freebsd.org Received: from atlas.rccn.net (atlas.rccn.net [193.136.7.1]) by hub.freebsd.org (Postfix) with SMTP id 998BC14ED5 for ; Thu, 14 Oct 1999 07:39:45 -0700 (PDT) (envelope-from jpsp@rccn.net) Received: (qmail 30003 invoked by uid 1021); 14 Oct 1999 14:39:42 -0000 Received: from localhost (sendmail-bs@127.0.0.1) by localhost with SMTP; 14 Oct 1999 14:39:42 -0000 Date: Thu, 14 Oct 1999 15:39:42 +0100 (WEST) From: Joao Pagaime To: freebsd-questions@freebsd.org Subject: FreeBSD 3.2 / Slow SCSI Dell PowerEdge 4300 Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-freebsd-questions@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.ORG Hi all I have a very slow Pentium III/450 with 512MB RAM because disks tranfers are slow. Simple tests show a transfer rate of +/- 2MB/sec, when a PC with IDE can do easily at least 4 times that value. I think the problem is with the "Common Access Method" in the backplane, because although the controllers are found with no problem : ahc0: rev 0x00 int a irq 11 on pci2.4.0 ahc0: aic7890/91 Wide Channel A, SCSI Id=7, 16/255 SCBs ahc1: rev 0x03 int a irq 11 on pci2.6.0 ahc1: aic7860 Single Channel A, SCSI Id=7, 3/255 SCBs The backplane is reported as having only 3.3 MB transfer rate : pass2 at ahc0 bus 0 target 6 lun 0 pass2: Fixed Processor SCSI-2 device pass2: 3.300MB/s transfers Did anyone experience the same problem ? Can someone help me ? Any hints ? Any configurarion at the CAM level ? - I configured the kernel to debug CAM but I can only reboot the machine in a few hours... Thanks, Joao Pagaime PS: the disks are also reporter correctly : da1 at ahc0 bus 0 target 1 lun 0 da1: Fixed Direct Access SCSI-2 device da1: 80.000MB/s transfers (40.000MHz, offset 31, 16bit) da1: 8687MB (17793001 512 byte sectors: 255H 63S/T 1107C) da0 at ahc0 bus 0 target 0 lun 0 da0: Fixed Direct Access SCSI-2 device da0: 80.000MB/s transfers (40.000MHz, offset 31, 16bit) da0: 8687MB (17793001 512 byte sectors: 255H 63S/T 1107C) And here are a few miserable tests : Sparc Entreprise 1000 - very old : time dd bs=1000000 count=100 if=/dev/zero of=t 100+0 records in 100+0 records out real 0m22.640s user 0m0.055s sys 0m16.094s Dell PowerEdge 4300 (http://www.dell.com/products/poweredge/pe4300/index.htm) time dd bs=1000000 count=100 if=/dev/zero of=t 100+0 records in 100+0 records out 100000000 bytes transferred in 53.853144 secs (1856902 bytes/sec) real 0m55.553s user 0m0.001s sys 0m1.562s This makes very unhappy users ! thank again, -- FCCN - Fundacao para a Computacao Cientifica Nacional - Tel: 351-1-8440100 To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-questions" in the body of the message