For the past month of so, CirrusSearch has suddenly and randomly stopped working and given the message "An error has occurred while searching: We could not complete your search due to a temporary problem. Please try again later."

Our wiki has used CirrusSearch for a good while now with no issues, but recently our traffic has slowly been improving, and that is when trouble with search began. Restarting our VPS would solve the issue, but over time search would eventually go down again. As wiki traffic gradually increased, so did the frequency of the error, up to the point where search would go down daily.

Thinking it might be a memory use issue, I created a custom.options file in elasticsearch/jvm.options.d with the settings

-Xms3g

-Xmx3g

Nothing changed at first, as I didn't restart ElasticSearch, but the next morning search was down per usual, so I rebooted the VPS to get it working again. This time, that didn't solve the problem. The message "An error has occurred while searching" was still appearing.

I deleted the custom.options file I had created, and rebooted the VPS again. Still this didn't solve the problem.

To avoid not having any search function at all, we're now using the default mediawiki search. But I would much rather have CirrusSearch back again, so does anyone know what I should do to solve this issue and stop search giving nothing but error messages?