I noticed that you are using stat-prefetch; have you encountered any issues? I was finding that du's on complex directories could return abnormal results and/or errors, so it seemed that heavy metadata queries were occassionally glitchy. Without stat-prefetch, it's been fine. If you've been having good luck with it, maybe I should try again.
Just FYI, stat-prefetch is likely to be discontinued in the glusterfs--mainline--2.5 tree. the complexity and possible inconsistancies is not worth the performance gain (helps only an ls -l to be marginally faster). or we might just decide keep it for whatever gains it gives (and to not break your config spec files) since you always have the option of not loading it. avati -- Anand V. Avati
