[LAD] [LAU] cancelling I/O with libsndfile

[Dan Muresan]

> Regardless of whether you choose to measure latency or CPU load
> if you vary the st_blksize as specified in the previous email,
> you will not be able distinguish between the two values of
> st_blksize due to the influence of other factors.

What are you talking about? How can one vary st_blksize or choose a
preferred value for it? Are you assuming that I am writing a kernel
driver? Why?

If you meant the actual request size, then I think that (1) none of us
have performed measurements and (2) as I stated, if no measurements
have been performed, and if the implementation allows it, standard
recommendations should be obeyed.

> The behavior of fread() can be dubious for files accessed
> via NFS with respect to incomplete reads (ie EAGAIN). The
> only solution to this is to use read().

Please detail this somewhat. NFS was one of the use-cases I mentioned
in the beginning (and I actively use it).

>> else address the issues that arise from breaking the rules (i.e.
>
> Breaking what rules?

K&R C and even CS1 choices (fread / fwrite), unless you have a reason
to break them... Not that I would be at that level...

> You provide concrete proof that doing block sized reads makes
> any positive performance improvement and I'll implement block
> sized reads and buffering.

You have already said you would accept patches and contributions for
this specific issues (a userspace cache) in past e-mails. Are you
retracting (or qualifying) the offer? In any case, you already have
the VIO layer, which certainly WFM -- my programs work.

> Until you can show concrete proof I consider this issue closed.

Which issue? I was merely discussing choices. And I was arguing that
YOUR VIO code is a GOOD thing. Uh, please don't remove it :)

Anyway, I have found sndfile to be an extremely valuable library.


-- Dan