>> I was able to track down a OS X tool to test the performance of the >> ATA drive/controller combination (DiskBanger, from Apple's CHUD suite >> of performance testing tools). > > Can you post this, or give an URL?
I will, but I could not get the downloaded files to work correctly, even after several attempts. You might need a Apple Developer login, I think you can get a free one. <ftp://ftp.apple.com/developer/Tool_Chest/Testing_-_Debugging/ Performance_tools/> Alternate: go to developer.apple.com and type 'CHUD' in the search box. P.S.- CHUD stands for "Computer Hardware Understanding Development", for what it's worth. After a bit of investigating, I found the CHUD suite on my developer CD's. I had to manually get the *.pax archive out of the *.pkg, because there was a incompatibility between to version of the dev tools on my machine and the CHUD .pkg. I couldn't just install the .pkg. I also had to mount a .dmg once I got the pieces out of the .pax in order to get the DiskBanger utility. Maybe you'll have a easier time. I don't plan on trying to compare the numbers reported by DiskBanger to other testing utilities. I tried to use TimeDrive in Classic, but the numbers it reported were much less than TimeDrive in OS 9.x, so I knew it would not be a good test for OS X. > I did this mainly because I could not get OS X to boot from my > Adaptec 2930 UltraSCSI card. I considered getting an ATTO UW SCSI > card, which is supposedly bootable, but I also wanted to consolidate > all my SCSI drives and reduce the noise in my office. I have tried three different ATTO cards. One of them (the oldest) was not recognized by OS X at all, the others I cannot boot from, but I can use drives attached once the system boots. I will try the Adaptec (3900 series) cards once I replace them in our video suites with the ATA100 cards. I thought it interesting that the Media 100 people specifically state that the Adaptec cards are not compatible with v8. They recommend the ATTO cards and the ATTO RAID software. The skeptic in me thinks ATTO is paying them money ;) >> Yes, the CPU has to touch almost all the data on a IDE bus, while=20 >> SCSI controllers off-load much of the processing from the CPU.=20 > > That's no longer true and hasn't been since the advent of "Mode 4 > PIO"=20 > drives in about 1996. These are driven by DMA and can sustain quite > high=20 > transfer rates with low CPU loading - but only if driven by an > appropriat= > e=20 > device driver.=20 > > In the early days of this tech, many implementations were extremely=20 > buggy, so Windows is very cautious when enabling DMA. Most Windows=20 > machines more than a couple of years old won't enable it > automatically.=20 > Linux was bolder but hit problems on some hardware. > > I don't know what OS X does, but I doubt it uses PIO... I was aware of DMA, but you point out that the chances of your system using it are questionable. The same is true of tagged-command queueing, there are some ATA drives that support it, but not many drivers do. > Mind, the ATAPI API is much more basic than SCSI - no asynch xfers, > no=20 > disconnect etc. SCSI can still do much more. Yes, the old Ford vs Ferrari. One is better, but it is only worth it to a few. Charles Dostale [EMAIL PROTECTED] System Manager Silver Oaks Communications 824 17th Street Moline IL 61265 http://www.silveroaks.com -- Unsupported OS X is sponsored by <http://lowendmac.com/> Support Low End Mac <http://lowendmac.com/lists/support.html> Unsupported OS X list info <http://lowendmac.com/lists/unsupported.html> --> AOL users, remove "mailto:"; Send list messages to: <mailto:[EMAIL PROTECTED]> To unsubscribe, email: <mailto:[EMAIL PROTECTED]> For digest mode, email: <mailto:[EMAIL PROTECTED]> Subscription questions: <mailto:[EMAIL PROTECTED]> Archive <http://www.mail-archive.com/unsupportedosx%40mail.maclaunch.com/> Using a Mac? Free email & more at Applelinks! http://www.applelinks.com
