cdrom changes in test13-pre2 slow down cdrom access by 70%

David Mansfield
2000-12-22T22:55:33Z

Jens,

The cdrom changes that went into test13-pre2 really kill the performance
of my cdrom. I'm using cdparanoia to read audio data, and it normally
reads at 2-3x. Since test13-pre2 it's down to .6 - .7x. I've reverted
the following files to the ones from test13-pre1 and it's back to
normal:

drivers/cdrom/cdrom.c
drivers/ide/ide-cd.c
drivers/ide/ide-cd.h
drivers/scsi/sr.c
drivers/scsi/sr.h
drivers/scsi/sr-ioctl.c
drivers/scsi/sr-vendor.c
include/linux/cdrom.h

My hardware is:

Uniform Multi-Platform E-IDE driver Revision: 6.31
ide: Assuming 33MHz system bus speed for PIO modes; override with
idebus=xx
AMD7409: IDE controller on PCI bus 00 dev 39
AMD7409: chipset revision 3
AMD7409: not 100% native mode: will probe irqs later
AMD7409: disabling single-word DMA support (revision < C4)
ide0: BM-DMA at 0xf000-0xf007, BIOS settings: hda:DMA, hdb:pio
ide1: BM-DMA at 0xf008-0xf00f, BIOS settings: hdc:pio, hdd:pio
hda: CREATIVE CD5230E, ATAPI CDROM drive
ide0 at 0x1f0-0x1f7,0x3f6 on irq 14
hda: ATAPI 52X CD-ROM drive, 128kB Cache, DMA
Uniform CD-ROM driver Revision: 3.11

The only IDE device (as you can see) is the cdrom drive.

This is a huge patch, is there some way I could break it apart to see
what the relevant changes are?