You mentioned it ran out of memory in the search module. Perhaps a back log of nodes to be indexed is contributing to the problem. You can configure the number of nodes it will try to index in one cron run at admin->settings->search under the indexing throttle setting. Perhaps a smaller number there would help.
I think this was indeed the problem, because the cron job hadn't finished in weeks and it now no longer throws the memory error. As I said, this is a busy community site with a LOT of posting going on.
Thanks.
Lynn S.
------ Mama, homeschooler, writer, activist, spinner & knitter http://www.siprelle.com
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