On Thursday 06 March 2003 14:46, Christian Herzyk wrote: > Hi there, > > Am Donnerstag, 6. März 2003 20:48 schrieb Alan: > > On Thu, Mar 06, 2003 at 02:41:20PM -0500, Ernie Schroder wrote: > > > I'm getting ready to take Gentoo_2 off line and replace mobo and > > > processor I was looking at hdd's this morning and saw Western > > > Digital 80 and 120 gig udma 133 drives at both the same pricethe > > > difference is that the 80 gig has 8 megs of cache and the 120 > > > 2gigs.both claim a seek
ooops 2 megs > > > > ^^^^^ Gigs??? > > > > > time of 9.1ms. could some one voice an opinion here.(as if I have > > > to look far on this list for an opinion :) ) Which would you buy? > > > > More cache is always better performance, but if it means you can > > get the extra 40G.... Kinda hard to say. I got myself some of the > > WD 80G/8m drives a couple of months ago and have been quite happy. > > There was a bigger price difference between the 80 and 120 at that > > point though :) > > > > Tough decision, I guess it really comes down to space or > > performance. Granted, I can't give you quantitative evidence of the > > performance of the 8m vs 2m cache. > > I have the WD 80G drive with 2MB Cache, so I will just post my > values. > > > My hdparm results: > > > > phoenix alan # hdparm /dev/hdf > > > > /dev/hdf: > > multcount = 16 (on) > > IO_support = 0 (default 16-bit) > > unmaskirq = 0 (off) > > using_dma = 1 (on) > > keepsettings = 0 (off) > > readonly = 0 (off) > > readahead = 8 (on) > > geometry = 155061/16/63, sectors = 156301488, start = 0 > > /dev/hda:/dev/hda: multcount = 8 (on) IO_support = 0 (default 16-bit) unmaskirq = 0 (off) using_dma = 1 (on) keepsettings = 0 (off) readonly = 0 (off) readahead = 8 (on) geometry = 1247/255/63, sectors = 20044080, start = 0 Ernie root # hdparm -Tt /dev/hda /dev/hda: Timing buffer-cache reads: 128 MB in 0.86 seconds =148.84 MB/sec Timing buffered disk reads: 64 MB in 3.13 seconds = 20.45 MB/sec > multcount = 16 (on) > IO_support = 1 (32-bit) > unmaskirq = 1 (on) > using_dma = 1 (on) > keepsettings = 0 (off) > readonly = 0 (off) > readahead = 8 (on) > geometry = 9729/255/63, sectors = 156301488, start = 0 > > > phoenix alan # hdparm -Tt /dev/hdf > > /dev/hdf: > > Timing buffer-cache reads: 128 MB in 0.80 seconds =159.60 > > MB/sec Timing buffered disk reads: 64 MB in 2.07 seconds = 30.86 > > MB/sec > > /dev/hda: > Timing buffer-cache reads: 128 MB in 0.50 seconds =256.00 MB/sec > Timing buffered disk reads: 64 MB in 2.04 seconds = 31.37 MB/sec > > Quite strange that my cache reads are much faster, probably it's teh > controller. > > > phoenix alan # dmesg | grep hdf > > hdf: WDC WD800JB-00CRA1, ATA DISK drive > > hdf: 156301488 sectors (80026 MB) w/8192KiB Cache, > > CHS=155061/16/63, UDMA(100) > > Kernel command line: root=/dev/hda8 hdd=ide-scsi > ide0: BM-DMA at 0xd400-0xd407, BIOS settings: hda:DMA, hdb:DMA > hda: WDC WD800BB-53BSA0, ATA DISK drive > hda: 156301488 sectors (80026 MB) w/2048KiB Cache, CHS=9729/255/63, > UDMA(100) > > So it seems that in this small "benchmark" the cache doesn't score > too much perhaps there are some better things to run like bonnie or > dbench. > > Greetings > > Christian Seems that the larger cache doesn't make much difference. This is my UDMA/66 WD 20 gig/2megs cache: /dev/hda: multcount = 8 (on) IO_support = 0 (default 16-bit) unmaskirq = 0 (off) using_dma = 1 (on) keepsettings = 0 (off) readonly = 0 (off) readahead = 8 (on) geometry = 1247/255/63, sectors = 20044080, start = 0 Ernie root # hdparm -Tt /dev/hda /dev/hda: Timing buffer-cache reads: 128 MB in 0.86 seconds =148.84 MB/sec Timing buffered disk reads: 64 MB in 3.13 seconds = 20.45 MB/sec I guess I can expect to see a pretty healthy increase in speed with the UDMA/133. If there was a great advantege to the larger cache, I'd be inclined to go that way, after all, who needs 120 gigs? Of course 2 years ago, I asked who needs 20 gigs? -- Regards, Ernie 100% Microsoft and Intel free -- [EMAIL PROTECTED] mailing list
