linuxaudio.org

>> > I never much liked the VIO layer. It was only ever added because

quoted text
>> > a large number of people requested it. I think its fragile and

>> > it exposes too much of libsndfile internals to the user.

There is one remaining issue that I have discovered while writing

jack-file, and which can only be addressed via a VIO layer of some

sort. While reading a FLAC file, the sndfile request size stream looks

like
8188, 8188, 8188, 8192 etc (bytes)
This is with the user continuously requesting 16384 frames. You will

notice that these are uneven block sizes. If I understand correctly

e.g. the stat(2) page, these are inefficient syscalls:
"The st_blksize field [of a struct stat] gives  the "preferred"

blocksize for efficient file system I/O. (Writing to a file in smaller

chunks may cause an inefficient read-modify-rewrite.)"
Without a VIO layer (or a libsndfile user-space cache), this is not

solvable by the user at higher abstraction layers.
-- Dan

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