Re: [alsa-devel] snd_pcm_writei VS snd_pcm_mmap_writei

On Fri, 19 Nov 2010, Irfan Shaikh wrote:

Hello,

    Please tell me
    a) Difference between working of snd_pcm_mmap_writei and snd_pcm_writei ?
    b) Performance wise which is better ?

The mmap functions does not require user space / kernel context switches.

    When i use gettimeofday almost profile time comes almost same for both of them.

With current hw power, there are no major differences.

Jaroslav

----- Jaroslav Kysela perex@perex.cz Linux Kernel Sound Maintainer ALSA Project, Red Hat, Inc.