This blog forms part of the http://performanceGuru.com website which focuses on performance tuning UNIX-like Operating Systems (including Linux).
I think the release announcement says it best:Introductionnfs4trace is a DTrace provider for NFSv4. The probes and their arguments are a nearly one-to-one mapping with the NFSv4 protocol.Familiarity with the D language and the NFSv4 protocol will allow you to use nfs4trace to profile, debug, or otherwise analyze the OpenSolaris NFSv4 client or server. Some possible uses:profile NFSv4 compounds collate by tag, address, … gather their frequency, duration, … snoop-like functionality without the problems of the physical network encrypted packets packet fragmentation which interface(s) to watch watch for interesting events activity on the callback channel delegations issued, recalled, returned locking, errors, lease renewals, state recovery, … A kernel developer can combine these probes with the rest of the DTrace probes to do very in-depth analysis.For those lacking familiarity of D and/or NFSv4, there will be example D scripts that make use of nfs4trace. Watch the announcements section for details as they become available.
So go play and help improve this provider, as well as the NFS implementation in OpenSolaris - go on, you know it makes sense...http://opensolaris.org/os/project/nfs4trace/