On Thu, Oct 05, 2000 at 04:06:01PM -0500, Ben Kochie wrote: > yep.. that's about normal.. you are hitting DISK preformance limits.. not > chain limits.. here's what I get on a 10k RPM disk on an alpha 600 with a > symbios card.. you are also hitting the PCI bus limit of 133MB. this is > an active box.. so the numbers are a little low :( (load is about 2 right > now) > > Timing buffered disk reads: 64 MB in 3.53 seconds = 18.13 MB/sec > Timing buffer-cache reads: 128 MB in 3.06 seconds = 41.80 MB/sec > > that's for normal UltraWide > > this one is a K6-2 450, with a buslogic (mylex) scsi card, and a 7200 RPM > disk (i think) (backup server, no load) > > Timing buffered disk reads: 64 MB in 5.54 seconds = 11.55 MB/sec > Timing buffer-cache reads: 128 MB in 3.28 seconds = 39.02 MB/sec > > and finaly, a dual celeron with a 7200 RPM ide drive > > Timing buffered disk reads: 64 MB in 3.47 seconds = 18.44 MB/sec > Timing buffer-cache reads: 128 MB in 1.49 seconds = 85.91 MB/sec > > all drives are fairly recent (less than 1 year old) IBM ultrastars, and > IDE is a deskstar. > > On Thu, 5 Oct 2000, Michael Josephson wrote: > > > I'm running Debian (kernal 2.2.17) on a server at > > home: PIII 700 256MB ram with an Adaptec 29160 SCSI > > controller and an IBM ultra 160 hard drive. When I run > > hdparm -Tt /dev/sda, it reports: > > > > Timing buffer-cache reads: ...= 128 MB/sec > > Timing buffered disk reads: ...= 19.05 MB/sec > > > > I'm not expecting max performance, but 19 MB/sec is a > > helluva lot slower than 160 MB/sec. Anyone have any > > thoughts on this? ---end quoted text--- I've got a new IBM ultrastar 7200rpm (purchased in June). The box currently has no load. According to your numbers, I should be getting at least twice the 19MB/sec. I'm not too worried about this. But I'm trying to understand as much as I can about the hardware...I'm a programmer, not a doctor :-) I haven't noticed any performance issues, but the results of hdparm indicates to me that things could use some tuning. mj -- Michael Josephson Software Development/Web Administration mjj at mjjtech.net www.mjjtech.net --------------------------------------------------------------------- To unsubscribe, e-mail: tclug-list-unsubscribe at mn-linux.org For additional commands, e-mail: tclug-list-help at mn-linux.org