Selecting the "Set Affinity" option

When you click on this entry, you are presented with a dialog box that shows the number of processors that Windows has detected in your system, as shown in the second and third illustrations.

Windows XP

Windows Vista

I find that for CPU-intensive tasks such as the Copernic Desktop Search indexer, better overall system behavior is obtainable by setting the CPU Affinity to one or other of the CPUs, as demonstrated in the first illustration. Even in periods of heavy indexing, no more than 50 percent of the total processor resource is consumed by the indexer,

When both boxes are checked, I've found the indexer gobbling up to 80 or 90 percent of the CPU resource and behavior is no better than with a single-CPU PC (typically resulting in intermittent periods when the responsiveness of other concurrent applications fluctuates dramatically).

What we have here is the case of hardware features having leapt ahead of software capabilities. The rather crude ability to manually set the Processor Affinity of individual tasks, as just described, must be carried out one task at a time, and worse than that every single time that you restart your system.

I have no insight as to whether Microsoft provides an interface for software makers (such as Copernic, to mention just one, and they're all in the same boat, each and every one of them) to build into their applications a permanent run-time configuration option for you to control the application's processor affinity.

I see this as a major oversight, especially for power users me who want to get the ultimate performance out of their multi-core systems.

History shows that we always keep throwing ever more complex multimedia and other types of workloads on our systems, so the need to have better control over the multiple processor cores via Processor Affinity will need to be addressed both by operating system vendors and the application providers alike.

I haven't even looked at Linux or Macintosh operating systems to find out if the above also applies to them. My guess is that it does, but I'll gladly stand to be corrected.

{moscomment}