[Cin] PreRoll in Cin Digest, Vol 43, Issue 13,

[Phyllis Smith]

Interesting and quite helpful.  Thanks.

> While I have not tested the current state of the git repository, I thought
> I might add a few comments about testing performance in general from the
> perspective of a retired systems programmer. I am a fan of Cinelerra-GG and
> use it for burning bluray disks so I hope to be able to test the new code
> before long.
>
It will be interesting to hear your results of burning bluray disks --
especially if you have good speakers where you might be able to
differentiate audio options of LPCM and tsMuxer results as I could not.

> ...
> Any settings within a given application, eg cache or pre-roll, will need
> to be measured in a controlled environment which means rebooting the
> computer to clear the file system file cache. Otherwise, any request for
> data that has been previously read may be satisfied from the operating
> systems file cache regardless of the settings in the application.
>
Measuring this in a controlled environment is very useful to a programmer
to improve the code if possible.  The problem is for a user, there is no
such thing as a controlled environment and just how they "feel" is all that
matters.  So the best that can be done is for programmers to take advantage
of the methods you outline.  I do think that the "preroll" of 1.0 seconds
as opposed to 0.5 seconds seems more consistent for me as a user -- it made
me "feel" better!

> ...
> It goes without saying that any use of swap space will radically degrade
> performance unless that swap space is on a solid state drive and the swap
> partition is quite generous in size.
>
I gave up on swap space years ago -- if you have to swap, you may as well
reboot.
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