Re: [gtk-list] Re: Weird behavior - memory gets sucked up

[Eric Harlow <linuxgeek yahoo com>]

> > Putting the code in a block that gets called 100 times  (as
opposed to
> > 10000 or so) seemed to significantly reduce the memory footprint. 
The
> > gtk_progress_bar_update function needs to be called in the loop to
> > cause the leak.  For my really large log file, the old code ends up
> > acting like an MS app - sucking down 90% of memory and causing disk
> > swap. 
> 
> Yes, and this is the right thing to do.  Even if
> gtk_progress_bar_update() used an integer comparison instead of a
> floating point wouldn't help you as much as you'd like.  Why would you
> want an extra function call overhead in your loop if is that size,
> anyway?  Far better to only call once every 10 or 100 lines.  This
> also dedicates more CPU to actually reading the file instead of
> updating the progressbar in ways that no human can appreciate.  Even
> if the progressbar checked before doing an update (even with an
> integer comparison), you'd still lose a considerable amount of CPU
> that could be used to read/process your file --- not a good tradeoff.
> 
> Can you think of a situation where it would be useful to update the
> progress bar after every processed line?  Given the speed with which a
> line is processed and the purpose of a progress bar, I cannot.

I think that a library should be smart enough to know when a
programmer is being inefficient.  In the first pass of developing
code, getting the code to work is the first priority.  Once working,
the speedup/cleanup begins.  

In my case, I was using small files to do some testing.  Once I got
the basic bugs knocked out, I tried to import a 10 meg file - bad move.
The two slowest part of the operation became the repainting of the
progress bar instead of the file i/o.  The library should be smart
enough to say - hey, the progress bar didn't move, don't bother
updating.  I *shouldn't* have to write that code myself.  I *could* if
I wanted to speed it up a bit after it was working. 

 -Eric
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