Jetpack Monitor false negatives?

Has anyone else experienced receiving JetPack Monitor alerts which seem like they might be false positives? (Or should these be called “false negatives”?)

When we started getting them, we optimized the heck out of our site, instituting caching and other optimizations. It loads pretty quickly now, but we continue to get alerts. The site is image heavy, but they are served from the JetPack CDN and many are lazy-loaded.

The alerts come when no one associated with the site was viewing the site, or logged into the admin area. We had zero or very few visitors at the time of the alerts. (They mostly occur in the very early hours of the morning.) No backups were being taken, no software or plugin updates were taking place. Access logs don’t show visits from search engine bots at the times of the alerts.

Soon after each of the last several notices, I’ve checked with our hosting company (DreamHost). Each time, they have checked and found that neither our web server or mysql server were offline. And they also found that our website has not triggered their “procwatch” limits. (We are on a shared server.) They report that there were no server issues that would have caused the site to be offline or unresponsive. Our error and access logs give no clues, and show no PHP errors.

DreamHost has basically said that no, the site was not offline. Which I suppose leaves “unresponsive” as the trigger of the alerts.

I’ve also checked with JetPack Support. They have been no help so far, offering only the most general advice to “use fewer plugins” or “disable the alert service”. But they have been unable to provide anything specific that might help us troubleshoot. No reported plugin conflicts either.

I’d love to hear from other people who use JetPack Monitor. Do you receive inexplicable alerts at times? If so, how often? Is there any number of notices of occasional, short outages that we should just ignore as “normal”? (DreamHost says that ideally we should be receiving no notices.)

Any suggestions for troubleshooting?

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