Path: utzoo!attcan!uunet!aplcen!uakari.primate.wisc.edu!gem.mps.ohio-state.edu!apple!agate!ucbvax!mtxinu!sybase!sisyphus!dg
From: dg@sisyphus.sybase.com (David Gould)
Newsgroups: comp.databases
Subject: Re: Client/Server processes and implementations
Keywords: Client Server Processes
Message-ID: <7134@sybase.sybase.com>
Date: 19 Nov 89 02:56:02 GMT
References: <2184@kodak.UUCP> <6895@sybase.sybase.com> <122@tacitus.tfic.bc.ca> <7037@sybase.sybase.com> <125@tacitus.tfic.bc.ca>
Sender: news@sybase.sybase.com
Reply-To: dg@sybase.com (David Gould)
Organization: Sybase, Inc.
Lines: 35

In article <125@tacitus.tfic.bc.ca> clh@tacitus.UUCP (Chris Hermansen) writes:
>
>From our (rather limited) experience with VMS, I don't blame you for
>implementing your own multitasking here; it probably was easier than sorting
>out all the SYS$HOOEY that you would have needed to make things work under
>VMS.
> ...
I agree that VMS can be complex, but it provides better facilities than
most (you may insert 'unix' here if you like) platforms we run on, even
though we did not design with VMS specifically in mind.  Nonetheless we ask
VMS or any OS for as few services as we can.

> ... more about Sybase tasking vs. OS processes ...
>tasks".  I would not dispute that your company has good reasons for
>approaching the problem this way; however, I feel it is reasonable to
>wonder exactly how much measurable benefit there is to your theoretically
>better approach.
> ...
It is reasonable to wonder, but not all reasonable to expect an answer to
'exactly how much measurable benefit ...'. This is of course proprietary
information, and of course, varies with the workload.  I can say that my
experience with VMS is that on a loaded system typically 40% to 60% of the
cpu is used in system modes (intr stack, kernal mode, exec mode), but on
a maxed out VMS system running only the Sybase server, quite a bit less
than 10% of the cpu is in used in system state.  I will also say that we
don't spend that time in our tasking services either.  As always, these
sort of figures depend almost everything, so your mileage may vary.

>Chris Hermansen                         Timberline Forest Inventory Consultants

- dg

------  All opinions are mine and may or may not represent Sybase Inc.  ------
David Gould       dg@sybase.com        {sun,lll-tis,pyramid,pacbell}!sybase!dg
                  (415) 596-3414      6475 Christie Ave.  Emeryville, CA 94608