pulseaudio: setup buffer attrs
Request reasonable buffer sizes from pulseaudio. Without this
pa_simple_write() can block quite long and lead to dropouts,
especially with guests which use small audio ring buffers.
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Signed-off-by: malc <av1474@comtv.ru>
diff --git a/audio/paaudio.c b/audio/paaudio.c
index 858ca81..75e3ea0 100644
--- a/audio/paaudio.c
+++ b/audio/paaudio.c
@@ -289,6 +289,7 @@
{
int error;
static pa_sample_spec ss;
+ static pa_buffer_attr ba;
struct audsettings obt_as = *as;
PAVoiceOut *pa = (PAVoiceOut *) hw;
@@ -296,6 +297,15 @@
ss.channels = as->nchannels;
ss.rate = as->freq;
+ /*
+ * qemu audio tick runs at 250 Hz (by default), so processing
+ * data chunks worth 4 ms of sound should be a good fit.
+ */
+ ba.tlength = pa_usec_to_bytes (4 * 1000, &ss);
+ ba.minreq = pa_usec_to_bytes (2 * 1000, &ss);
+ ba.maxlength = -1;
+ ba.prebuf = -1;
+
obt_as.fmt = pa_to_audfmt (ss.format, &obt_as.endianness);
pa->s = pa_simple_new (
@@ -306,7 +316,7 @@
"pcm.playback",
&ss,
NULL, /* channel map */
- NULL, /* buffering attributes */
+ &ba, /* buffering attributes */
&error
);
if (!pa->s) {
