At zfsday 2012, I gave a talk on ZFS performance analysis and tools, discussing the role of old and new observability tools for investigating ZFS, including many based on DTrace.
Sergey Gitinsky‘s insight:
Post by Brendan Gregg — ZFS and DTrace guru about measuring performance of ZFS with his own tools.»ZFS can boil ocean» :)top 6 measuring tools
metaslab_free.d45 minutes video and 66 slides. This is worth watching for specialists!