[vlc-devel] [PATCH] Patch to fix bug #1532, and improve http seek times.

[Rémi Denis-Courmont]

Le vendredi 13 juin 2008 19:31:05 Bill C. Riemers, vous avez écrit :
> Presumably that value is checked when setting p_sys->b_seekable.
> Basically I am just making the code say
> if this stream is seekable, it is also fast seekable.   According to
> Rémi Denis-Courmont, FASTSEEK should actually
> mean non-blocking seek.

CAN_FASTSEEK means that seeking is fast/cheap. Of course, you can find 
blocking operations are seomtimes faster than non-blocking ones, but 
_typically_ not... Indeed, using my hard-drive, and even the hard-drive on 
the other computer is my flat (over CIFS) is order of magnitude faster than 
using an HTTP server outside. If a demux absolutely must seek, then CAN_SEEK 
should be used. If seeking is just an optimization, then CAN_FASTSEEK should 
be used.

Even if the Seek callback of HTTP could be made non-blocking, it will still 
add blocking operations. Worse yet, setting HTTP to CAN_FASTSEEK will break 
the access filters. Basically, putting HTTP in CAN_FASTSEEK is a negation of 
the CAN_FASTSEEK concept. Once you do that, one might as well identify 
CAN_FASTSEEK with CAN_SEEK...

-- 
Rémi Denis-Courmont
http://www.remlab.net/