From c1b6a87b27b569cda135da05b53cc98aa9ca37cb Mon Sep 17 00:00:00 2001 From: Wim Taymans Date: Thu, 20 Aug 2009 13:40:27 +0200 Subject: alsa-sink: reduce the amount of smoother updates Exponentially increase the amount of time between smoother updates. We start with a 2ms interval and increase up to 200ms intervals. Smoother updates and the resulting linear regression take a fair amount of CPU so we want to reduce the amount of updates. --- src/modules/alsa/alsa-sink.c | 26 ++++++++++++++++++++++---- 1 file changed, 22 insertions(+), 4 deletions(-) (limited to 'src') diff --git a/src/modules/alsa/alsa-sink.c b/src/modules/alsa/alsa-sink.c index e3707ae7..c3694729 100644 --- a/src/modules/alsa/alsa-sink.c +++ b/src/modules/alsa/alsa-sink.c @@ -68,6 +68,9 @@ #define TSCHED_MIN_SLEEP_USEC (10*PA_USEC_PER_MSEC) /* 10ms -- Sleep at least 10ms on each iteration */ #define TSCHED_MIN_WAKEUP_USEC (4*PA_USEC_PER_MSEC) /* 4ms -- Wakeup at least this long before the buffer runs empty*/ +#define SMOOTHER_MIN_INTERVAL (2*PA_USEC_PER_MSEC) /* 2ms -- min smoother update interval */ +#define SMOOTHER_MAX_INTERVAL (200*PA_USEC_PER_MSEC) /* 200ms -- max smoother update inteval */ + #define VOLUME_ACCURACY (PA_VOLUME_NORM/100) /* don't require volume adjustments to be perfectly correct. don't necessarily extend granularity in software unless the differences get greater than this level */ struct userdata { @@ -115,6 +118,8 @@ struct userdata { pa_smoother *smoother; uint64_t write_count; uint64_t since_start; + pa_usec_t smoother_interval; + pa_usec_t last_smoother_update; pa_reserve_wrapper *reserve; pa_hook_slot *reserve_slot; @@ -723,17 +728,27 @@ static void update_smoother(struct userdata *u) { now1 = pa_timespec_load(&htstamp); } + /* Hmm, if the timestamp is 0, then it wasn't set and we take the current time */ + if (now1 <= 0) + now1 = pa_rtclock_now(); + + /* check if the time since the last update is bigger than the interval */ + if (u->last_smoother_update > 0) { + if (u->last_smoother_update + u->smoother_interval > now1) + return; + } + position = (int64_t) u->write_count - ((int64_t) delay * (int64_t) u->frame_size); if (PA_UNLIKELY(position < 0)) position = 0; - /* Hmm, if the timestamp is 0, then it wasn't set and we take the current time */ - if (now1 <= 0) - now1 = pa_rtclock_now(); - now2 = pa_bytes_to_usec((uint64_t) position, &u->sink->sample_spec); + u->last_smoother_update = now1; + /* exponentially increase the update interval up to the MAX limit */ + u->smoother_interval = PA_MIN (u->smoother_interval * 2, SMOOTHER_MAX_INTERVAL); + pa_smoother_put(u->smoother, now1, now2); } @@ -906,6 +921,8 @@ static int unsuspend(struct userdata *u) { u->write_count = 0; pa_smoother_reset(u->smoother, pa_rtclock_now(), TRUE); + u->smoother_interval = SMOOTHER_MIN_INTERVAL; + u->last_smoother_update = 0; u->first = TRUE; u->since_start = 0; @@ -1622,6 +1639,7 @@ pa_sink *pa_alsa_sink_new(pa_module *m, pa_modargs *ma, const char*driver, pa_ca 5, pa_rtclock_now(), TRUE); + u->smoother_interval = SMOOTHER_MIN_INTERVAL; dev_id = pa_modargs_get_value( ma, "device_id", -- cgit