Multiple versus a single collection search with Verity

I have a simple question about Verity search collection.

We have been using verity for a number of years, but we have never done
any real performance testing in regards to a single collection versus many.

All documentation and articles argue for multiple small collections when
indexing for better indexing performance. But what is the performance
hit when searching 2 collections instead of 1 combined collection?

How about 4 collections instead of 1?

Thanks


--

Don Vaillancourt
Director of Software Development
WEB IMPACT INC.
phone: 416-815-2000 ext. 245
fax: 416-815-2001
toll free: 866-319-1573 ext. 245
email: donv@web-impact.com <mailto:donv@webimpact.com>
blackberry: donv@rogers.blackberry.net <mailto:donv@rogers.blackberry.net>
web: http://www.web-impact.com
address: http://maps.google.com
< http://maps.google.com/maps?f=q&hl=en&q=99+atlantic+ave,+toronto&ie=UTF8&z=15&ll=43.640765,-79.420767&spn=0.013448,0.04343&om=1&iwloc=addr>


This email message is intended only for the addressee(s) and contains
information that may be confidential and/or copyright.

If you are not the intended recipient please notify the sender by reply
email and immediately delete this email.

Use, disclosure or reproduction of this email by anyone other than the
intended recipient(s) is strictly prohibited. No representation is made
that this email or any attachments are free of viruses. Virus scanning
is recommended and is the responsibility of the recipient.