[vlc-devel] [WiP] core: make the background worker multithreaded

[Rémi Denis-Courmont]

Le keskiviikkona 11. heinäkuuta 2018, 9.31.01 EEST Steve Lhomme a écrit :
> On 2018-07-10 19:22, Rémi Denis-Courmont wrote:
> > Le tiistaina 10. heinäkuuta 2018, 20.11.44 EEST Romain Vimont a écrit :
> >> A way to speed up the preparsing consists in preparsing several inputs
> >> in parallel.
> > 
> > This has already been discussed. It brings intractable support issues.
> > 
> > Like media centers that don't handle or don't allow more than X
> > connection(s) (for a very small X), file system or storage whose
> > performance sucks when reading more than one node at a time, memory and
> > CPU consumption.
> 
> It's not either or in this case.

They both solve partially overlapping problems, so implementing one makes the 
other a lot less useful.

> It would be good to have the possibility to do it even if it's not the
> default and probably for VLC it should not be the default.

It's not a problem of default. To constrain CPU and memory, you can have a 
setting in the preferences, like avcodec-threads, because it's tied to the 
running system.

But for storage or network services, it is tied to the input item, not the 
running system, so a global preference setting is not helping at all. No 
matter how fast your CPU is, and how much RAM you have, if a network service 
fails with more than X outstanding requests per user, you have to obey. And if 
you try to read multiple large files on a CD or DVD at the same time, the 
performance will be much much worse than if you read them sequentially.

Frankly, I don't really care if this is implemented or not. Just don't be 
surprised that you get a lot of weird and/or angry bug reports.

-- 
レミ・デニ-クールモン
http://www.remlab.net/