I have two hard drives, hda and hdb, both UDMA66. hda has the ext3 root partition, a swap partition, and a FAT32 partition. hdb just has one 10Meg FAT32 partition. When I stream a .wav file from the FAT32 partition on hda through say XMMS, the total system load is very low, just a few percent cpu load. When I do the same, but from hdb's FAT32 partition, the cpu load hovers at around 30-50%. What is responsible for all the extra cpu activity in reading from the 2nd harddrive ?
