I was curious to make this, and then thought to share it
Excluded are players that I know would perform bad (Amarok, Exaile, ...) or myriad primitive GUI players
Test on low end P4 3GHz/512KB, RAM 1GB on Ubuntu 11.04 32bit
Every application is tested in clean session, w/o plugins, loaded with 15K tracks library (except DeadBeef lacking this feature)
Test by 5x1min tracks playback (wav, flac, mp3, ogg, m4a) although there weren't any noticeable differences between tracks formats and performance, because of which box plot is used for presentation.
Logging and monitoring by TOP
CPU test results
(http://i.imgur.com/EnmU8.png)
(http://i.imgur.com/hKHX7.png)
Physical memory (RES)
(http://i.imgur.com/WGcvx.png)
Not much mean variety compared to real user experiance, but perhaps considerable when using audio collection for backgroung playback or using low end PC