I have read a couple or articles on CommVault Online that say defragmentation of the Magnetic libraries is a good idea. Diskeeper, now Dymax IO, was listed as a certified product for online volumes. I am wondering if others defrag there libraries for performance purposes, and what products they use. I have read in older articles that the native windows defragmentation tool can be used. Also it states that it should be done outside of backup hours (makes sense). Any feedback or information would be appreciated.