Screenshot of (cf. background explanation by Ori Livneh) This "flame graph" visualizes which parts of the MediaWiki code consumed most CPU time on WMF servers in that hour, keeping track of which other parts they have been called from. The data that is used to generate the graph is supplied by an HHVM extension called ‘Xenon’, which snapshots server activity at regular intervals, showing which code is on-CPU. The code that generated this graph is available under a free license (CDDL)