[RC5] If you were writing our next client...

Richard J. Straka straka at lucent.com
Fri Apr 30 16:52:08 EDT 1999

Client Suggestion: Dynamic priorities based on other running processes/applications

I would like the client to be able to run at different priorities,
dependent on what other processes or applications are currently running,
and perhaps other OS-specific parameters - even while unattended.

For instance, consider that when your client machine runs backups (and
compresses data on writing), is being backed up over the network, is
running a compile, maybe sending or receiving a fax, maybe burning a
CD-ROM, etc., you might want the client to suspend crunching activity or
at least lower the priority.

The processes/applications could easily be identified by the end user
via the OS' standard "open file" interface and the degree of "nice"ness
be selected for each identified application. OS-specific activities
(e.g., file I/O,...) could be identified by the savvy client developer.

Another way to attack this problem is to stop crunching, see how much
CPU time is being chewed up by other processes, and based on the nominal
CPU load, run at some appropriate priority. Of course, load assessment
and implementation of this is dependent on the nature and
characteristics of the OS' scheduler. This is frankly kind of "iffy".

This should not really be necessary, but the client is designed to run
flat out, while most other applications are not. Even a good scheduler
in the OS cannot "do the right thing" when you're trying to compile code
and run the client simultaneously. It would try to give both
CPU-intensive applications 50% each (roughly). You really want the
client to take a rest under those conditions - independent of the OS' scheduler.

BTW, I don't know what to say about screen savers except that people
should be warned not to use CPU-hungry ones. But that's no change from
today's case.

Rich Straka
Lucent Technoilogies / Bell Laboratories

If only Microsoft had hired Linus Torvalds in 1991...they wouldn't have
Linux to worry about today.

To unsubscribe, send 'unsubscribe rc5' to majordomo at lists.distributed.net
rc5-digest subscribers replace rc5 with rc5-digest

More information about the rc5 mailing list