Audio-latency test results (audio buffer 3 x 256 bytes)

- the red reference line is the global audio buffer size , if this deadline is missed you will hear a sond drop-out.
- the white line is the actual scheduling latency, the ideal would be the time it takes to play 1 audio fragment.
- the green line is the time the CPU takes to execute an empty loop (which is calibrated at 80% of the fragment time)
- the yellow reference line is the len of one audio fragment (ideally the white line should stay close to yellow line)
this is used to simulate heavy CPU computations during the audio play, a typical example could be a synthesizer which computes the waveform to play in realtime.
since the thread runs with SCHED_FIFO priority, if this time goes up, then the cause could be the DMA / PCI / ISA contention on the system bus, or busy kernel I/O routines
- the white between +/-1ms is the % of time the total latency stays in the range between +/-1ms of the optimal latency.
- the white between +/-2ms is the % of time the total latency stays in the range between +/-2ms of the optimal latency.
- the green between +/-0.2ms is the % of time the CPU loop latency stays in the range between +/-0.2ms of the nominal CPU loop latency.
- the green between +/-0.1ms is the % of time the CPU loop latency stays in the range between +/-0.1ms of the nominal CPU loop latency.

X11 stress

/proc filesystem stress

disk write stress

disk copy stress

disk read stress