Re: max request size 1024KiB by default?

Lee Revell
2004-07-24T22:58:08Z

On Sat, 2004-07-24 at 07:27, Rudo Thomas wrote:
> > HD info:
> > /dev/hdc:
> >
> > Model=Maxtor 6Y160P0, FwRev=YAR41BW0, SerialNo=Y44K8TZE
> > Config={ Fixed }
> > RawCHS=16383/16/63, TrkSize=0, SectSize=0, ECCbytes=57
> > BuffType=DualPortCache, BuffSize=7936kB, MaxMultSect=16, MultSect=16
> > CurCHS=4047/16/255, CurSects=16511760, LBA=yes, LBAsects=268435455
> > IORDY=on/off, tPIO={min:120,w/IORDY:120}, tDMA={min:120,rec:120}
> > PIO modes: pio0 pio1 pio2 pio3 pio4
> > DMA modes: mdma0 mdma1 mdma2
> > UDMA modes: udma0 udma1 udma2 udma3 udma4 udma5 *udma6
> > AdvancedPM=yes: disabled (255) WriteCache=enabled
> > Drive conforms to: (null):
>

Your disk controller must not support that. It looks like the default
is 1024KiB or whatever the max your controller supports is:

drivers/ide/ide-disk.c:

if (drive->addressing == 1) {
ide_hwif_t *hwif = HWIF(drive);
int max_s = 2048;

if (max_s > hwif->rqsize)
max_s = hwif->rqsize;

blk_queue_max_sectors(drive->queue, max_s);
}

Lee