On Tue, 21 Jan 2020 03:13:20 +0100, Keyon Jie wrote: > > > > On 2020/1/20 下午8:44, Takashi Iwai wrote: > > Currently, the available buffer allocation size for a PCM stream > > depends on the preallocated size; when a buffer has been preallocated, > > the max buffer size is set to that size, so that application won't > > re-allocate too much memory. OTOH, when no preallocation is done, > > each substream may allocate arbitrary size of buffers as long as > > snd_pcm_hardware.buffer_bytes_max allows -- which can be quite high, > > HD-audio sets 1GB there. > > > > It means that the system may consume a high amount of pages for PCM > > buffers, and they are pinned and never swapped out. This can lead to > > OOM easily. > > > > For avoiding such a situation, this patch adds the upper limit per > > card. Each snd_pcm_lib_malloc_pages() and _free_pages() calls are > > tracked and it will return an error if the total amount of buffers > > goes over the defined upper limit. The default value is set to 32MB, > > Is this typo here? In the patch, "max_alloc_per_card = 32UL * 1024UL * > 1024UL * 1024UL", should be 32GB? Oh yes, it's an obvious typo. Fixed now. Thanks! Takashi _______________________________________________ Alsa-devel mailing list Alsa-devel@xxxxxxxxxxxxxxxx https://mailman.alsa-project.org/mailman/listinfo/alsa-devel
