#1 - June 24, 2013, 8:03 p.m.
Blizzard Post
We’ve been working hard to combat memory usage errors that users of low-end systems have encountered. There have been select moments where “Out of Memory” complications could cause the game to crash, and new safeguards are being added in Patch 5.4. The first step for us will be adding in a new dialog box should you run out of memory while loading saved variables for an addon.

What this means for users is instead of crashing, you will receive a pop-up message that an addon did not load properly: “Your computer does not have enough memory to load settings from the following AddOn. Please disable some AddOns.”

What this means for authors is in 5.4, your addon could be in a state where the saved variables do not load. If that ends up being the case, the addon will also be prevented from saving data upon logging out of the game. We feel it’s better for everyone to prevent valid data from accidentally being wiped by defaults.

This change will cause an event to fire when a player runs out of memory: “SAVED_VARIABLES_TOO_LARGE” (With the name of the addon as the first argument.) Please test your addons with low memory machines on the PTR and let us know if there are any issues.