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I’m dealing with a very similar scenario. I have a similar amount of traffic, and will get some unexplained spikes in memory usage that take my server down.

It’s pretty much impossible to diagnose the problem in development, as it really seems to be tied to our peak traffic times.

Does anyone have any good direction they can point me for simulating load?

Good idea with the wp-cache concept. My database traffic doesn’t seem to be dreadful, but it couldn’t hurt to back-off on the queries.

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