Re: Fix for slow process output processing (please test).

[David.Kastrup@t-online.de (David Kastrup)]

no-spam@cua.dk (Kim F. Storm) writes:

> David Kastrup and others have reported very slow processing of
> process output, particularly with the Linux kernel's scheduler
> giving emacs too much attention while starving the processing
> producing the output.
> 
> Below is a patch which introduces a small delay on reading output
> from such processes, without using global delays in processing other
> events (this is done by temporarily removing the process' file
> descriptor from the call to select and use a short timeout on the
> select instead.
> 
> I have not yet tested this extensively, but would like some feedback
> on whether it actually does have the intended positive effect on the
> processing of process output.  Could people who have experienced
> these problems pls. try the patch and give me feedback.

One thing that I mentioned might be a good idea is to cancel any
prospective delay on the next read when something is sent to the
process.  In that manner there will be no delay when some protocol is
talked instead of just output collected.

> The patch is against CVS emacs at the time of "server shutdown".

I have experimented around with several (quite more naive) approaches
myself, never reaching a point that would have been worth discussing,
let alone committing, so I don't have a reasonably clean process.c.
Could you send me a complete copy of yours in private mail?

Thanks.

-- 
David Kastrup, Kriemhildstr. 15, 44793 Bochum