Huge dictionary, 1 min to create, 6 to delete

[Rick Pasotto]

On Thu, 31 Aug 2000 00:12:52 -0700 in comp.lang.python, Emile van Sebille wrote:
> Can you pare the code down to an example the
> exhibits the problem and post it.  When I create
> a dictionary with 1M entries and exit, I experience
> no delay.

This is what I got on my machine (linux 2.2.16, PII 400, 192m):

<start prog>
import time

print "    ",time.ctime(time.time())
dct = {}
for i in range(1000000):
	try:
		k = str(i)
		v = k + ":" + k
		dct[k] = v
	except:
		print i
print "    ",time.ctime(time.time())
</end prog>

@tc:~/python$ date; python dict.py; date
Thu Aug 31 09:11:44 EDT 2000
    Thu Aug 31 09:11:44 2000
    Thu Aug 31 09:13:03 2000
Thu Aug 31 09:14:36 EDT 2000

Both the creation and the deletion took ~1m20s.

> "haaserd" <haaserd at yahoo.com> wrote in message
> news:39AD8BDA.84DB5BB3 at yahoo.com...
> > As a learning exercise, I decided to use the python
> > dictionary in a program which tries to create crossword
> > puzzles (solutions less clues).  In doing so I created a
> > dictionary with about 1,000,000 entries.  This takes about
> a
> > minute on my AMD 700 processor, with very little(no) disk
> > activity.
> >
> > My problem is that when the program ends, it takes about 6
> > minutes, during which there is very heavy disk activity.
> As
> > a test, I did a dict.clear(), and had the same result.
> >
> > Is this the garbage collection problem mentioned briefly
> in
> > a few discussions?  Or am I just hitting a Windows 98
> paging
> > problem unrelated to python?  I have 128 MB of memory.
> >
> > TIA
> >
> > Roger Haase
> >
> 
> 


-- 
"Moderation in temper is always a virtue; but moderation in
 principle is always a vice."
		-- Thomas Paine, _The Rights of Man_ (1791)
		   Rick Pasotto email: rickp at vnet.net