Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!shadooby!accuvax.nwu.edu!tank!shamash!com50!pwcs!stag!daemon From: to_stdnet@stag.UUCP Newsgroups: comp.sys.atari.st Subject: Hard drive questions Message-ID: <781@stag.UUCP> Date: 11 Apr 89 19:25:52 GMT Sender: daemon@stag.UUCP Lines: 44 From: stag!thelake!steve@bungia.mn.org (Steve Yelvington) Xorg@cup.portal.com (Peter Ted Szymonik) writes... > How fast are the trasnfer rates, again, this depends entirely on > the drive mech and which host adaptor you use. As a benchmark, my > Supra 30meg drive transfered 350Kps at 60-65ms, the 100meg ICD drive I > just put together flies at 550Kps and 35-40ms, it all depends on the > drive mech supplied with your drive (or the one you buy.) > I hacked together a Wren I (nominally 36 megabytes), one of the bargain Adaptec boards from Timeline and a Supra host adaptor. The ICD RATEHD program says I'm running a respectable 377kb/sec data transfer rate, but a shameful 527ms average seek rate. This is an old drive, but that seems more than a bit much. I have the drive mounted vertically -- is there a possibility that could affect the stepper's positioning of the heads? I'm running a 1:1 interleave -- could that be involved? > Is there caching? Yes, there are lots of PD and commercial > cacheing programs, but I haven't found them to be at all necessary > given the ST's blazing HD data transfer rates. Probably the only > thing left to speed drive access with be the new TOS 1.4 which will > improve FAT handling. > Because of the horribly slow seeks I'm getting, PATH searches can be painful. For that reason, I've installed Atze Dijkstra's DCACHE program with the argument cde=c18, creating a common cache for drives C, D and E of 18K. That's enough to keep all the directories in RAM as well as some smaller utilities, such as the file pager I use for UUCP stuff. It helps a lot and it's worth the RAM even on my small system (512K). DCACHE was published in this newsgroup about nine months ago. /* * UUCP: {uunet!rosevax,amdahl!bungia,chinet,killer}!orbit!thelake!steve * ARPA: crash!orbit!thelake!steve@nosc.mil * #member The ST Developers Network */