Poor SCSI performance in OSX vs OS 9

I am using a magneto optical drive to view images for a healthcare business.

The time to load images in the program via a 400mhz g4 OS 9 = 40 seconds and the time on an 800mhz g4 with OS X is somewhere around 60-70 seconds.

The MO drive is SCSI.

Does anyone have any ideas as to why this would be? Is there known issues with SCSI drivers in OSX, etc?
Thanks.

how much ram in each system?

SCSI support in OS X has never been optimal. Since Apple began phasing out SCSI with the original iMac (1998) it's not been a priority.

1gb in teh newer machine (the osx machine) and 512 in the earlier.

Classic mode runs a LOT slower. But it is acting like its reading at 1.3mb/s (61 seconds for 92 mb file). Perhaps it is supposed to be ultra scsi?

The weird thing is, when reading a second time, it loads completely from memory, doesn't access the MO at all. None of the other machines (that read faster) do this. It seems the reason it is taking so long is it is taking from the MO, storing to memory, and when finished, then reading from memory the data. Is there any way to change the memory handling?

yieldsign2 said:

I am using a magneto optical drive to view images for a healthcare business.

The time to load images in the program via a 400mhz g4 OS 9 = 40 seconds and the time on an 800mhz g4 with OS X is somewhere around 60-70 seconds.

The MO drive is SCSI.

Does anyone have any ideas as to why this would be? Is there known issues with SCSI drivers in OSX, etc?
Thanks.

Click to expand...

If the 800 GHz machine can dual boot it might be worthwhile to boot into OS9 for this particular app. I think OS9 just deals with SCSI better. do the two machines use the same kind of SCSI host adapter?