[OpenAFS] Performance issue with "many" volumes in a single /vicep?

Steve Simmons scs@umich.edu
Wed, 17 Mar 2010 12:50:48 -0400

We've been seeing issues for a while that seem to relate to the number =
of volumes in a single vice partition. The numbers and data are inexact =
because there are so many damned possible parameters that affect =
performance, but it appears that somewhere between 10,000 and 14,000 =
volumes performance falls off significantly. That 40% difference in =
volume count results in 2x to 3x falloffs for performance in issues that =
affect the /vicep as a whole - backupsys, nightly dumps, vos listvol, =

My initial inclination is to say it's a linux issue with directory =
searches, but before pursuing this much further I'd be interested in =
hearing from anyone who's running 14,000 or move volumes in a single =
vicep. No, I'm not counting .backup volumes in there, so 14,000 volumes =
means 28,000 entries in the directory.