7 tools for analyzing performance in Linux with bcc/BPF (opensource.com)
7 tools for analyzing performance in Linux with bcc/BPF (opensource.com)
Brendan Gregg introduces a
set of BPF-based tracing tools on opensource.com.
"Traditional analysis of filesystem performance focuses on block I/O
statistics—what you commonly see printed by the iostat(1) tool and plotted
by many performance-monitoring GUIs. Those statistics show how the disks
are performing, but not really the filesystem. Often you care more about
the filesystem's performance than the disks, since it's the filesystem that
applications make requests to and wait for. And the performance of
filesystems can be quite different from that of disks! Filesystems may
serve reads entirely from memory cache and also populate that cache via a
read-ahead algorithm and for write-back caching. xfsslower shows filesystem
performance—what the applications directly experience.
"