May 21, 2013 - by rachelbalik
A crucial problem in understanding latency - or response time - is that most presentations of latency data aren’t detailed enough. Frequently, the most important information is hidden, a problem that can be solved with heat maps. While a few analytics tools include heat maps, Brendan Gregg, Lead Performance Engineer at Joyent, found there were times when he wanted to convert a separate trace output into a heat map.
He’s solved this problem from himself (and incidentally, the rest of us) by writing trace2heatmap.pl, which will generate interactive SVGs. Joyent’s Cloud Analytics has built-in heat maps ready to use, in real time, with low overhead, that are production-ready, but for those looking to try these separately, Brendan has written a full blog post on the DTrace blog on Revealing Hidden Latency Patterns. It serves as a tutorial for understanding and implementing heat maps and also offers insight on using heat maps in production. Read it here while it’s still hot.*
*Brendan Gregg is not responsible for and does not endorse any bad puns that appear on the Joyent blog, or anywhere else on the web.