OpenEuphoria

Re: Apparent bug in 2.3

• Posted by Robert Craig <rds at RapidEuphoria.com> Dec 09, 2001
• 410 views

rforno writes:
> But when the program starts to
> use virtual memory, typed keys have no effect, the disk is constantly
> accessed, and the only way to stop the program is to hit ctrl-alt-del or the
> reset button.

When you use swap space,
performance can become extremely bad,
especially on algorithms like this, where
Euphoria has to internally access all the elements of
a huge sequence from start to end.  

Your statement:
      s &= n

will periodically require a complete new copy
of a huge sequence to be made. If this is done
using swap space it can eventually take
seconds or even minutes to complete.
Meanwhile, your keypresses appear to have no effect,
although if you wait long enough it should eventually stop.
That might be a *long* time.

Swap space works best when you only use a little of it,
or when your algorithm has high "locality of reference"
to data (which concatenation does not.)

Regards,
   Rob Craig
   Rapid Deployment Software
   http://www.RapidEuphoria.com