I have two discs, two maxtors as mather of fact. On older 15gig and a newer 20gig disc.
did some testing in linux with hdparm. worth mentioning is that I was not running PREEMPT and no Desktop-scheduler. Just most throughput-io-schedulers.
That shouldn't anyway affect the results of my hdparm testing.
the first drive: the 20 Gig did: 22 meg/s
the second: the 15 gig did: 26 meg/s
udma3 or udma4 didn't affect perfomance at all.
Thought this was kind of weird as I wasn't close at all filling the ata66 buss.
Tried with a newer 120 gig disc. result: 29 meg/s
This seemed very weird as i'm quite sure that disc can spit out more.
Benchmarked it with nvidias nforce4 driver on my desktop-computer and it could hold: 57 meg/s substained speed.
hmm, tried my 20 gig disc with the nforce4 controller and got 41 meg/s substained speed.
these values seemed more real.
Though that perhaps the hpt366 just slices its bandwidth. like 66 meg/s / channels. so i get 33 meg/s on each cable.
To test my theory I hooked both the discs on separate channels on the hpt366 and tried to run two hdparm -t's simultaniesly(?)
Seemed to work fine for a few tests, then something weird happened.
DMA totaly crashed on one of the first disc. hde in this case. still worked fine on the hdg.
turned on the dma again with hdparm on hde and tried again to do hdparm tests. The kernel starts to spit out loads of DMA errors and such. The hdg reported no problems what so ever and still performed good but the hde went down to 3.5 meg/s.
this was quite weird as the DMA worked fine for like two or three tests and then broke down. And during those tests that worked, both discs gave ~24 meg/s
Conclusion: the hpt366 is very bad. The harddrives can give more than the hpt366 can handle. And you have to look out for the dma to lockup.
Had plans run Software raid on the controller but as it seems now there is no point.
Sorry for my poor rush-english.
