IBM-DTLA-307045 very slow under 2.2.x

From: Neil Booth (
Date: Fri Feb 16 2001 - 20:18:54 EST

I have a SOYO "SY-5EMA+ Super 7" motherboard, with a K6-2 processor.
The 45 Gig IBM drive hangs the BIOS if I let it autodetect it, so I
turn off autodetection for IDE2 primary where it sits. This is probably
not relevant.

My problem is that "hdparm -tT dev/hdc" gives atrocious

 Timing buffered disk reads: 64 MB in 22.81 seconds = 2.81 MB/sec

with approximately 25% CPU usage. By contrast, for /dev/hda it

 Timing buffered disk reads: 64 MB in 11.49 seconds = 5.57 MB/sec

with 100% CPU, which is still poor, but somewhat better. The relevant
part of my dmesg is

VP_IDE: IDE controller on PCI bus 00 dev 39
VP_IDE: not 100% native mode: will probe irqs later
ide0: BM-DMA at 0xd000-0xd007, BIOS settings: hda:DMA, hdb:DMA
ide1: BM-DMA at 0xd008-0xd00f, BIOS settings: hdc:DMA, hdd:DMA
hdb: CD-ROM 40X/AKU, ATAPI CDROM drive
hdc: IBM-DTLA-307045, ATA DISK drive
ide0 at 0x1f0-0x1f7,0x3f6 on irq 14
ide1 at 0x170-0x177,0x376 on irq 15
hda: QUANTUM FIREBALL CR13.0A, 12416MB w/418kB Cache, CHS=1582/255/63
hdc: IBM-DTLA-307045, 43979MB w/1916kB Cache, CHS=5606/255/63
hdb: ATAPI 40X CD-ROM drive, 128kB Cache

hdparm -i /dev/hdc gives:-

Model=IBM-DTLA-307045, FwRev=TX6OA50C, SerialNo=YM0YML23878
Config={ HardSect NotMFM HdSw>15uSec Fixed DTR>10Mbs }
RawCHS=16383/16/63, TrkSize=0, SectSize=0, ECCbytes=40
BuffType=DualPortCache, BuffSize=1916kB, MaxMultSect=16, MultSect=off
CurCHS=16383/16/63, CurSects=16514064, LBA=yes, LBAsects=90069840
IORDY=on/off, tPIO={min:240,w/IORDY:120}, tDMA={min:120,rec:120}
PIO modes: pio0 pio1 pio2 pio3 pio4
DMA modes: mdma0 mdma1 *mdma2 udma0 udma1 udma2 udma3 udma4 udma5

Trying to set the DMA mode with -X34 and -d1 seems to have no effect.

Is this normal, or am I doing something wrong?


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This archive was generated by hypermail 2b29 : Fri Feb 23 2001 - 21:00:14 EST