Resurrected's server issues over the D2R Items past few weeks have gotten more severe. This culminated in several instances of downtime in the past week, where a global outage was caused, Blizzard say, by a surge in traffic. "This was a new level that our servers had not ever experienced before, not even at launch," reads the post on the Blizzard forums.
The issue was further aggravated due to an update that we released earlier in the day designed to improve performance during game creation. Both of these factors overloaded our global database and caused it to take a long time out.
We were able to reverse the Friday update that we had previously released hoping to ease the load on servers leading into Sunday while also giving us the chance to dig deeper into what caused the issue."
As it turned out, rolling back the patch wasn't enough. Sunday brought a bigger growth in traffic and servers were again smashed. This time on Monday. The linked article is very long and meticulously detailed in its breakdown of the causes.
However, particularly Blizzard place the blame on the old code used in making games and joining them, and also to reading characters from databases. "We did optimize this service in a variety of ways to be more modern technology, but as we've said before that a large portion of our issues are due to buy D2R Ladder Items the game's creation," says the post.
