[comp.sys.hp] Question on HP9000/800

stevem@pserv.UUCP (Steve Mestad) (08/08/89)

Question for the 800 series users out there.....

According to the catalogs I have seen, the series 800 systems use the
same io buses and controllers as the series 500 systems.  In particular
I recall the disk and serial boards are the same.

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....

Thanks....
Steve Mestad  (email.....stevem%pserv@src.honeywell.com)

plb@cbnewsi.ATT.COM (peter.l.berghold) (08/08/89)

As to HP9000 Series 800 io throughput:   I am the system administrator for 
3 HP9000/850S machines and was previously the same for an HP9000/825 and an
HP9000/840.   These machines seem to perform very well in terms of throughput
if issues such as swap space, tuneable parameters, and device contention are
considered.   I am familiar with the HP9000/500 and HP9000/3xx machines and I 
think that there is a wealth of difference between these machines and the 
HP9000/8xx machines all around.


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Silly opinions expressed by this author are not neccesarily the viewpoints 
of my employer or anybody else for that matter.
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kinsell@hpfcdj.HP.COM (Dave Kinsell) (08/11/89)

>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