Xref: utzoo comp.sys.amiga:61045 comp.sys.amiga.tech:13097 Path: utzoo!attcan!uunet!tut.cis.ohio-state.edu!zaphod.mps.ohio-state.edu!samsung!munnari.oz.au!metro!news From: matth@extro.ucc.su.OZ.AU (Matthew Hannigan) Newsgroups: comp.sys.amiga,comp.sys.amiga.tech Subject: Re: Tiny Tiger hard disk Summary: remove or adjust upwards the Maxtransfer figure in devs:mountlist Keywords: hard disk tiny tiger maxtransfer FFS Message-ID: <1990Jul2.074747.19497@metro.ucc.su.OZ.AU> Date: 2 Jul 90 07:47:47 GMT References: <1227@metaphor.Metaphor.COM> Sender: news@metro.ucc.su.OZ.AU (news) Reply-To: matth@extro.ucc.su.OZ.AU (Matthew Hannigan) Distribution: comp.sys.amiga,comp.sys.amiga.tech Organization: University Computing Service, Uni. of Sydney, Australia. Lines: 50 In article <1227@metaphor.Metaphor.COM> djh@dragon.metaphor.com (Dallas J. Hodgson) writes: >In article sam@ms.uky.edu (Mike Mills) writes: >>I recently bought a used Tiny Tiger hard disk with a ST157-N (48 meg) drive for >>my a500. I got a good deal on it, but I'm not impressed with its speed. Less >>than 50K/sec for reads and writes, no matter how big the buffer is. >> >>The Tiny Tiger plugs into the parallel port. I was wondering where the >>bottleneck is that makes it so slow; is it the parallel port, the scsi >>interface, or the x500.device driver? I was hoping that if it was the driver >>that a faster, more efficient version might be available somewhere? > >I've been happy with the Tiny-Tiger's speed; in real-world performance, I'm >amazed that it runs as fast at is does. I remember the MAST folks quoting >its xfer rate at 500KB/sec, raw. I'm not going to refute or support this >claim, but I do know this; the actual loop that performs the block transfers >is VERY tight. It goes something like this: > > loop: nop > move.b ciaaprb,(a0)+ > dbra d0,loop ... interesting stuff deleted ... >+----------------------------------------------------------------------------+ >| Dallas J. Hodgson | "This here's the wattle, | I have just bought a Tiny-Tiger 45Mb drive and had it diskperf'd at the shop before I took it away. At first it only gave 50k/sec. BUT there is a option in the mountlist for FFS called MaxTransfer. On some boot up disks supplied with the TT, Maxtransfer is set to 32. On others, it is missing. When booted with a disk with no Maxtransfer the transfers rates are as expected and are quite close to the A590's DMA figures. So, the conclusion is to either adjust upwards (say 128) the Maxtransfer figure, or remove altogether. Exactly what subtle interactions are going on here warrants further investigation. Could someone in the know tell us exactly what Maxtransfer is for? The 1.3 book is not particularly enlightening. Is it size or speed fr'instance? Regards, -Matt H PS. I have an Amiga 500 with PAL, 1.3 roms