It seems Matthew Dillon wrote: > :Hmm, I've just played around a bit, it seems we are hit by interrupt > :latency or something, if you limit the transfer to 128k, which allows > :the ATA controller to fetch it in one go, you will see the expected > :transfer rates. Now I dont see this on PCI based controllers, and that > :hints that the problem could be the fact that the two onboard controllers > :sits on irq 14 & 15 making them the lowest priority devices in the system, > :and that could cause the interrupt latency I'm seeing which then again > :causes the bad transfer rates on transfers that need to transfer more > :that one transaction full of data (ie max 128k). > : > :-Søren > > The larger transfers are probably choking the IDE drive's pipelining > capabilities. That's my guess, anyway. I avoid IDE like the plague.
No, not true, if the same drive is put on a PCI based ATA controller you get the expected transfer speed upto the drives cache size. -Søren To Unsubscribe: send mail to [EMAIL PROTECTED] with "unsubscribe freebsd-current" in the body of the message
