Oh, hey, Fail Whale, what up?

If you tweet, you’ve probably been seeing a lot of messages welcoming back (or complaining about) the Fail Whale.

Twitter’s iconic “over capacity” message has been making a lot of cameos over the past two days, for reasons Twitter’s status blog says are down to a “system-side issue.” The first post addressing the issue came yesterday just before noon PST:

We had a system-side issue this morning starting around 0800 Pacific that resulted in twitter.com experiencing two 30 minute back-to-back incidents over roughly one hour. The problem has largely been addressed, but we aren’t quite to 100 percent yet.

Twitter most recently addressed the issue less than an hour ago, saying that features like search and friend counts were being disabled until functionality improves:

We are experiencing site availability issues — additional latency and errors — this morning. We’re working to address these issues.

Update: 9:07 PDT / 16:07 UTC: Users may notice that their timelines are updating slowly. All tweets will eventually be delivered.

Update: 9:32 AM PDT / 16:32 UTC: To help stabilize the site we’re turning off a set of features including but not limited to: Twitter Search, hovercards, web sidebar data (trends, friends counts, etc), and profile image uploads.

Twitter has not posted any updates indicating when users can expect issues to resolve, but says they’re “working to recover from this problem.”