> My server is a K6-500 with 43MB of RAM, standard x86 hardware. The such a machine was good in its day, but that day was what, 5-7 years ago? in practical terms, the machine probably has about 300 MB/s of memory bandwidth (vs 3000 for a low-end server today). further, it was not uncommon for chipsets to fail to cache then-large amounts of RAM (32M was a common limit for caches configured writeback, for instance, that would magically cache 64M if set to writethrough...) > OS is Slackware 10.0 w/ 2.6.7 kernel I've had similar problems with the with a modern kernel, manual hdparm tuning is unnecessary and probably wrong. > To tune these drives, I use: > hdparm -c3 -d1 -m16 -X68 -k1 -A1 -a128 -M128 -u1 /dev/hd[kigca] if you don't mess with the config via hdparm, what mode do they come up in? > hda: WD 400JB 40GB > hdc: WD 2000JB 200GB > hdg: WD 2000JB 200GB > hdi: IBM 75 GXP 120GB > hdk: WD 1200JB 120GB iirc, the 75GXP has a noticably lower density (and thus bandwidth). > Controllers: > hda-c: Onboard controller, VIA VT82C596B (rev 12) > hdd-g: Silicon Image SiI 680 (rev 1) > hdh-k: Promise PDC 20269 (rev 2) > /dev/hda: Timing buffered disk reads: 42 MB in 3.07 seconds = 13.67 MB/sec > /dev/hdc: Timing buffered disk reads: 44 MB in 3.12 seconds = 14.10 MB/sec not that bad for such a horrible controller (and PCI, CPU, memory system) > /dev/hdg: Timing buffered disk reads: 68 MB in 3.04 seconds = 22.38 MB/sec > /dev/hdi: Timing buffered disk reads: 72 MB in 3.06 seconds = 23.53 MB/sec > /dev/hdk: Timing buffered disk reads: 66 MB in 3.05 seconds = 21.66 MB/sec fairly modern controllers help, but not much. > /dev/md0: Timing buffered disk reads: 70 MB in 3.07 seconds = 22.77 MB/sec > /dev/md1: Timing buffered disk reads: 50 MB in 3.03 seconds = 16.51 MB/sec since the cpu/mem/chipset/bus are limiting factors, raid doesn't help. > I would appriciate any thoughts, leads, ideas, anything at all to point me in > a direction here. keeping a K6 alive is noble and/or amusing, but it's just not reasonable to expect it to keep up with modern disks. expecting it to run samba well is not terribly reasonable. plug those disks into any entry-level machine bought new (celeron, sempron) and you'll get whiplash. plug those disks into a proper server (dual-opteron, few GB ram) and you'll never look back. in fact, you'll start looking for a faster network. regards, mark hahn. - To unsubscribe from this list: send the line "unsubscribe linux-raid" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
