Rate limit needed (Was: Re: [PATCH] fix #47996)

[Roger Larsson]

On Thursday 07 November 2002 18.04, David Faure wrote:
> On Thursday 07 November 2002 18:09, Josef Weidendorfer wrote:
> > I once suggested a work around if the copying is controlled by KDE:
> > Do it in an unwatched directory (e.g. in directory ".hidden/" of the 
target
> > dir) and then do a move.
> 
> Users don't want that. It would mean that they can't "watch the file grow as
> it is being downloaded". It would all appear to be broken.
> 

FAM or whatever kind of report that is used needs to be rate limited.
In Real Time systems you often have to do that to prevent an event to drown
the rest of the system. This is even used in the Linux kernel [I think it went 
in]. The problem there is that you can get so many interrupts that you have
no time left to do the needed processing... So when a limit is reached - 
interrupts are turned of and the device is polled on timer instead.

This could be done in this case too. When there are few events. Report them 
all. If there are many collect and merge before reporting.

Another trick used in Real Time systems is to lower the priority of the event
generator. Then it can not produce more events than can be processed.

This is something to try in this case - try to run FAM with a really low nice!
What happens?

/RogerL
-- 
Roger Larsson
Skellefteå
Sweden