I've got a problem with RAID performance that seems to not be addressed anywhere.
The System:
ASUS A7V333R, 1800+, 512MB RAM
IDE0: 20 GB Maxtor
IDE1: DVD Master, DVD Burner Slave
RAID 0 - 2 x 60 GB IBM 60GXP (Master/Master), Promise LITE on board (A/V Settings)
Radeon VE Dual Monitor
ATI TV Wonder in Slot 3, LAN 10/100 in Slot 4
When I test the RAID drives (in Pinnacle Studio 8 or SiSoft Sandra) I get performance of 60 - 70 K READ but only 15K WRITE. The Maxtor tests at 28K READ, 25K WRITE. One of the IBM drives (in another computer) tested alone at about 32K READ, 28K WRITE. The drive is used almost exclusively for Video so the large stripes of the Promise LITE are OK. The drive captures video with no dropped frames but will begin to drop frames if the drive is not completely defragged. (This is probably a combination of the low Write speed and the known tendency of the Promise controller to have spiky behavior.)
Sandra suggests confirming that Write Verify is off but I think this is because it thinks it's a SCSI array. As nearly as I have been able to determine, Maxtor is the only company that has an IDE Write Verify Mode and that is only used for initial burn in. However, I can't think of any other reason for such a difference between Read and Write. Certainly any DMA or IRQ conflicts should affect both Read and Write.
For reference, I did disable USB 2.0 and got Read to go from about 48K to over 60K in Pinnacle but it had no impact on Write. I have also tried pulling out the TV card and disabling the IEEE 1394 port. These changes had not impact at all on performance. Any ideas?
The System:
ASUS A7V333R, 1800+, 512MB RAM
IDE0: 20 GB Maxtor
IDE1: DVD Master, DVD Burner Slave
RAID 0 - 2 x 60 GB IBM 60GXP (Master/Master), Promise LITE on board (A/V Settings)
Radeon VE Dual Monitor
ATI TV Wonder in Slot 3, LAN 10/100 in Slot 4
When I test the RAID drives (in Pinnacle Studio 8 or SiSoft Sandra) I get performance of 60 - 70 K READ but only 15K WRITE. The Maxtor tests at 28K READ, 25K WRITE. One of the IBM drives (in another computer) tested alone at about 32K READ, 28K WRITE. The drive is used almost exclusively for Video so the large stripes of the Promise LITE are OK. The drive captures video with no dropped frames but will begin to drop frames if the drive is not completely defragged. (This is probably a combination of the low Write speed and the known tendency of the Promise controller to have spiky behavior.)
Sandra suggests confirming that Write Verify is off but I think this is because it thinks it's a SCSI array. As nearly as I have been able to determine, Maxtor is the only company that has an IDE Write Verify Mode and that is only used for initial burn in. However, I can't think of any other reason for such a difference between Read and Write. Certainly any DMA or IRQ conflicts should affect both Read and Write.
For reference, I did disable USB 2.0 and got Read to go from about 48K to over 60K in Pinnacle but it had no impact on Write. I have also tried pulling out the TV card and disabling the IEEE 1394 port. These changes had not impact at all on performance. Any ideas?
