From owner-freebsd-hackers Sat Oct 7 19:42:53 1995 Return-Path: owner-hackers Received: (from root@localhost) by freefall.freebsd.org (8.6.12/8.6.6) id TAA11962 for hackers-outgoing; Sat, 7 Oct 1995 19:42:53 -0700 Received: from aslan.cdrom.com (aslan.cdrom.com [192.216.223.142]) by freefall.freebsd.org (8.6.12/8.6.6) with ESMTP id TAA11947 for ; Sat, 7 Oct 1995 19:42:47 -0700 Received: from localhost.cdrom.com (localhost.cdrom.com [127.0.0.1]) by aslan.cdrom.com (8.6.12/8.6.9) with SMTP id TAA27014; Sat, 7 Oct 1995 19:42:12 -0700 Message-Id: <199510080242.TAA27014@aslan.cdrom.com> X-Authentication-Warning: aslan.cdrom.com: Host localhost.cdrom.com didn't use HELO protocol To: Chuck Robey cc: Stefan Esser , "Kenneth D. Merry" , hackers@freebsd.org Subject: Re: VLB Disk Controllers In-reply-to: Your message of "Sat, 07 Oct 1995 22:33:58 EDT." Date: Sat, 07 Oct 1995 19:42:12 -0700 From: "Justin T. Gibbs" Sender: owner-hackers@freebsd.org Precedence: bulk >On Sun, 8 Oct 1995, Stefan Esser wrote: > >I just did that 10 times in a row with my 2842, and reading differing >over a 2:1 range. I think there's some windage here that makes your >comparison suspect. Try it a few tries in a row on the same drive. narnia# ./disklate /dev/rsd1 Command overhead is 1308 usec (time_4096 = 2749, time_8192 = 4191) transfer speed is 2.8409e+06 bytes/sec narnia# !! ./disklate /dev/rsd1 Command overhead is 1310 usec (time_4096 = 2751, time_8192 = 4191) transfer speed is 2.84322e+06 bytes/sec narnia# !! ./disklate /dev/rsd1 Command overhead is 1273 usec (time_4096 = 2752, time_8192 = 4230) transfer speed is 2.77012e+06 bytes/sec narnia# !! ./disklate /dev/rsd1 Command overhead is 1305 usec (time_4096 = 2749, time_8192 = 4192) transfer speed is 2.83721e+06 bytes/sec narnia# !! ./disklate /dev/rsd1 Command overhead is 1310 usec (time_4096 = 2752, time_8192 = 4194) transfer speed is 2.84056e+06 bytes/sec narnia# !! ./disklate /dev/rsd1 Command overhead is 1298 usec (time_4096 = 2750, time_8192 = 4202) transfer speed is 2.82092e+06 bytes/sec And on a partition: narnia# ./disklate /dev/rsd1e Command overhead is 1353 usec (time_4096 = 2823, time_8192 = 4292) transfer speed is 2.78737e+06 bytes/sec narnia# !! ./disklate /dev/rsd1e Command overhead is 1396 usec (time_4096 = 2835, time_8192 = 4275) transfer speed is 2.84511e+06 bytes/sec narnia# !! ./disklate /dev/rsd1e Command overhead is 1379 usec (time_4096 = 2827, time_8192 = 4274) transfer speed is 2.83049e+06 bytes/sec narnia# !! ./disklate /dev/rsd1e Command overhead is 1387 usec (time_4096 = 2832, time_8192 = 4277) transfer speed is 2.83483e+06 bytes/sec narnia# !! ./disklate /dev/rsd1e Command overhead is 1392 usec (time_4096 = 2829, time_8192 = 4267) transfer speed is 2.84952e+06 bytes/sec I don't get much variance. -- Justin T. Gibbs =========================================== Software Developer - Walnut Creek CDROM FreeBSD: Turning PCs into workstations ===========================================