From: Dave Pickles [davep@nugate.demon.co.uk]
Sent: Wednesday, February 02, 2000 2:02 PM
To: Everhart, Glenn (FUSA)
Subject: RE: VMS wish - performance

On Mon, 31 Jan 2000, you wrote:
>Dave -
>I'd certainly be interested in seeing your mods. Was it my code
>you upgraded? Haven't looked at the Fortran part in ages...
>Glenn Everhart
>everhart@gce.com
>thanks

No problem.

My intention was to set up a mechanism to back up the files users most
often need restored onto on-line storage, as recovery from backups was
taking far too much operator time. In the end the volume of data and the
speed of copying made the idea impractical.

I managed about a x3 speed-up overall (VMS 7.1 Alpha BTW). The biggest
gain came from setting sensible file allocation and extend sizes.
Overlapping I/O was another good move, though the benefit was not as great
as I hoped. The remainder came from 'tidying up' bits of code, and it was
here that I found some minor tweaks yielded a benefit totally out of
proportion.

Please feel free to use the code for any purpose you wish.

Dave Pickles
