On Mon, Jul 6, 2026 at 3:19 PM yesreal <[email protected]> wrote: > > Write buffer size max over p.
https://reviews.freebsd.org/D58064 > 2026年7月6日(月) 22:43 yesreal <[email protected]>: >> >> Hopefully >> >> 2026年7月6日(月) 21:14 Christos Margiolis <[email protected]>: >>> >>> On Mon Jul 6, 2026 at 12:15 AM EEST, Kevin Bowling wrote: >>> > Hi, >>> > >>> > I am working on a more complete pipewire audio sink >>> > (audio/pipewire-spa-oss-ng) and ran into an interesting case where a >>> > user has an interface with 10 channels on one dsp device. >>> > >>> > In sys/dev/sound/pcm/channel.h we currently have: >>> > #define CHN_2NDBUFMAXSIZE 131072 >>> > >>> > This is workable but results in a tighter bound than my sink requests. >>> > >>> > I am wondering if we should dynamically scale, something like this: >>> > >>> > #define CHN_2NDBUFMAXSIZE_DEFAULT 131072 >>> > #define CHN_2NDBUFMAXSIZE_LIMIT 1048576 >>> > >>> > static uint32_t >>> > chn_2ndbuf_maxsize(struct pcm_channel *c) >>> > { >>> > struct snd_dbuf *bs = c->bufsoft; >>> > uint64_t bytes; >>> > >>> > /* e.g. allow up to about 100 ms of the actual stream. */ >>> > bytes = (uint64_t)bs->align * bs->spd / 10; >>> > >>> > if (bytes < CHN_2NDBUFMAXSIZE_DEFAULT) >>> > bytes = CHN_2NDBUFMAXSIZE_DEFAULT; >>> > if (bytes > chn_2ndbuf_maxsize_limit) >>> > bytes = chn_2ndbuf_maxsize_limit; >>> > >>> > return (uint32_t)bytes; >>> > } >>> > >>> > I can send a complete patch for review if it seems like a reasonable >>> > direction. >>> > >>> > Regards, >>> > Kevin Bowling >>> >>> Feel free to propose the patch and add me as a reviewer, I was actually >>> meaning to either remove this or refactor this. Thank you! >>> >>> Christos >>>
