[support] cron job crashing server, and how many users is too many?

[Grandmother Spider]

I have a Drupal cron job (4.7) that crashes the web server--just hangs 
but never returns a specific error message; if I let it run, it just 
churns. I've let it go for five minutes before finally shutting it 
down. Its hanging brings down the whole shooting match. The logs tell 
me only that a segmentation fault occurred.

Very possibly related, whenever I try to do any administration related 
to the user table--for instance, call up the troll module admin 
pages--the site hangs similarly. This is a busy site with nearly 7500 
registered users in the table. How many users are too many users? I 
experience a similar but not nearly as dire slowdown on another site on 
the same box with more than 5500 registered users; calling up admin 
pages with users on it takes a bit but does complete, and its cron job 
completes in maybe 10 seconds.

I just recently upgraded both sites to 4.7.x from 4.6. Anything anyone 
could tell me would be useful. Thanks.

Lynn

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Mama, homeschooler, writer, activist, spinner & knitter
http://www.siprelle.com

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