Thinking Methodically about Performance – “Performance issues can be complex and mysterious, providing little or no clue to their origin. In the absence of a starting point—or a methodology to provide one—performance issues are often analyzed randomly: guessing where the problem may be and then changing things until it goes away. While this can deliver results—if you guess correctly—it can also be time-consuming, disruptive, and may ultimately overlook certain issues. This article describes system-performance issues and the methodologies in use today for analyzing them, and it proposes a new methodology for approaching and solving a class of issues.” - Brendan Gregg in ACM Queue, December 10, 2012
Brendan spoke at LISA12 on Performance Analysis Methodologies (slides here), presumably the video will be available soonish. In the meantime, you can see his LISA10 talk Visualizations for Performance Analysis.
ZFS fundamentals: transaction groups – “I’ve continued to explore ZFS as I try to understand performance pathologies, and improve performance. A particular point of interest has been the ZFS write throttle, the mechanism ZFS uses to avoid filling all of system memory with modified data. I’m eager to write about the strides we’re making in that regard at Delphix, but it’s hard to appreciate without an understanding of how ZFS batches data. Unfortunately that explanation is literally nowhere to be found. ” – Adam Leventhal
Catching up on some things I forgot to mention earlier…
Robert Mustacchi has posted:
Brendan on Active Benchmarking (first in a series)
…and illumos news can be found on the illumos blog.