I've just realized that maybe I should be asking "what is the nature of
this potential problem?" that you're working to correct? My site has a
grand total of around 12,000 subscribers on all lists, and I just looked
at the signup files, they are all 47k-49k in size.  I don't know what
the "recommenced" size range is, or what might 'go wrong' if they grow
too large.

>>> [log in to unmask] 10/3/2005 6:26:57 PM >>>
I timed a test of deleting 5000 (well, really 4900) records using
REGISTER
... OFF, and found that Listserv does ~200 names per minute (on our
site;
ymmv). So deleting 275000 names will take about 23 hours. I can break
this
up into smaller chunks, but regardless the web interface is
inaccessible/unusuable when one of these things is running. Click on
the
web interface, nothing happens for however long- wonderful customer
service. I can do it several early mornings, but while that removes
most
of the impact from SU customers (although a university never really
sleeps), it's not good for international customers. I can't even
realistically announce outages, because we can't email 120k
subscribers
over 1900 lists (yes, we can let list owners know). And regardless of
which way I go, it's a pain to manage in chunks.

Probably I should have done this long ago, but I didn't even realize
it
was a (potential) problem.

- Listserv List Manager
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