[pulseaudio-discuss] [PATCH 2/2] loopback: Track and use average adjust time

[Tanu Kaskinen]

On Mon, 2017-04-17 at 21:37 +0200, Georg Chini wrote:
> @@ -327,11 +335,20 @@ static void adjust_rates(struct userdata *u) {
>      }
>  
>      /* Allow one underrun per hour */
> -    if (u->iteration_counter * u->adjust_time / PA_USEC_PER_SEC / 3600 > run_hours) {
> +    if (u->iteration_counter * u->real_adjust_time / PA_USEC_PER_SEC / 3600 > run_hours) {
>          u->underrun_counter = PA_CLIP_SUB(u->underrun_counter, 1u);
>          pa_log_info("Underrun counter: %u", u->underrun_counter);
>      }
>  
> +    /* Calculate real adjust time */
> +    now = pa_rtclock_now();
> +    if (!u->source_sink_changed) {
> +        u->adjust_counter++;
> +        u->real_adjust_time_sum += now - u->adjust_time_stamp;
> +        u->real_adjust_time = u->real_adjust_time_sum / u->adjust_counter;
> +    }
> +    u->adjust_time_stamp = now;
> +
>      /* Rates and latencies*/
>      old_rate = u->sink_input->sample_spec.rate;
>      base_rate = u->source_output->sample_spec.rate;
> @@ -364,7 +381,9 @@ static void adjust_rates(struct userdata *u) {
>      pa_log_debug("Loopback latency at base rate is %0.2f ms", (double)latency_at_optimum_rate / PA_USEC_PER_MSEC);
>  
>      /* Calculate new rate */
> -    new_rate = rate_controller(base_rate, u->adjust_time, latency_difference);
> +    new_rate = rate_controller(base_rate, u->real_adjust_time, latency_difference);
> +
> +    u->source_sink_changed = false;

This "source_sink_changed = false" assignment would be better right
after the code that checks its value, at least based on this patch
alone. But maybe later patches use this variable too in a way that
makes this suggestion less good?

Otherwise looks fine.

-- 
Tanu

https://www.patreon.com/tanuk