[jed-users] Re: del_region() tremendously slow

[Ulli Horlacher <framstag@xxxxxxxxxxxxxxxxxxxx>]

On Mon 2025-01-27 (23:21), John E. Davis wrote:
> Morten Bo Johansen <mbj@xxxxxxxxx> wrote:
> 
> > I just happened to stumble into this rather abnormal use case: mark and
> > delete about two million lines in a file. With del_region(), it takes about
> > 8 seconds to do so on my oldish computer. With the competition (Emacs), it
> > happens in the blink of an eye. Why is del_region() so slow?

I have a similar problem with jed in edt mode (yes, I am an old VMS user).
Deleting about (only) 100k lines last virtually forever :-}


> I rewrote the delete_region function to improve its peformance.
> Testing shows that it is now about 150 times faster than before.

Great!

In edt.sl there is:

define edt_cut()
{
   variable b;
   ifnot (dupmark()) return;
   b = whatbuf();
   setbuf(edt_pbuf);
   erase_buffer();
   setbuf(b);
   copy_region(edt_pbuf);
   del_region();
}

Is here copy_region() the slowing down problem-function?


-- 
Ullrich Horlacher              Server und Virtualisierung
Rechenzentrum TIK
Universitaet Stuttgart         E-Mail: horlacher@xxxxxxxxxxxxxxxxxxxx
Allmandring 30a                Tel:    ++49-711-68565868
70569 Stuttgart (Germany)      WWW:    https://www.tik.uni-stuttgart.de/
REF:<20250128042121.34BE454D2B@xxxxxxxxxxx>
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