Path: utzoo!attcan!uunet!tut.cis.ohio-state.edu!ucbvax!hplabs!hpfcdc!hpfcdj!kinsell From: kinsell@hpfcdj.HP.COM (Dave Kinsell) Newsgroups: comp.sys.hp Subject: Re: Question on HP9000/800 Message-ID: <17330001@hpfcdj.HP.COM> Date: 11 Aug 89 00:14:22 GMT References: <105@pserv.UUCP> Organization: Hewlett Packard -- Fort Collins, CO Lines: 28 >On the series 500, a sustained transfer will move pretty well on the >larger disks, running 750k+ bytes/sec (timed)....The series 300 will >run about 300k- bytes/sec (timed).....However file access on the 300 >seems to beat the 500 every time....Dramatically in most cases. >My question is this, has this been fixed on the 800's so that they get >the 500 speed on large transfers and 300 speed on small accesses? >(E.g. the 500's are slow due to high overhead which has been fixed?) >Or is the 800 access slow like the 500 due to controller hw limits.... >Or is something going on that I missed.... I think you're overemphasizing the effects of the I/O hardware, and underemphasizing the disk throughput and the file system. Both the 300 and 800 use the BSD file system, and perform virtually identically when used with the same disks in these sorts of tests. The 500 file system was proprietary, and most likely behaves differently. Sustainable throughputs for the 300/800 systems with a 7937H disk are 420-480k/sec, depending on tuning. The 800 can deliver 700 k/sec when used with the HP-FL version of that disk. >Thanks.... >Steve Mestad (email.....stevem%pserv@src.honeywell.com) You're welcome.... Dave Kinsell kinsell@hpfcmb.HP.COM