Sims affected by weird ' user is offline' behaviour

Hello there dear Lindens,

For some time now, I am experiencing weird behaviour in some sims that I'd like to refer to as the 'user offline' issue.
We are talking about a sim that is not seemingly lagging to death (relatively stable FPS), does not have a huge script return time (relatively low) and had only a few physical collissions. It 'is' a heavy populated zone however, but often this issue comes up wether or not there's lots of people around.
The issue is that users are often not treated as actually being online in the sim. It's a very random occuring happening, not consistent and I have no idea how the reproduce this effect either, yet its still quite frequent.
This offline behaviour obviously causes some Instant Messages to get lost upon sending them to the people inside the sim, which they will receive sometime later on when logging in again (or in their e-mails). Teleport Invitations the same thing, and also the worst case: Product sales not being delivered upon purchase which makes most unaware customers think they have been ripped off by the vendor.

Having read trough the forums, I've noticed this is happening troughout the world in various sims, quite similar to the random 'auto-return' bug that was happening in some parcels and the major memory leak issues also happening in some sims (Might this issue be related somehow perhaps?)

I was wondering if this issue has been confirmed as well and looked into, because it honoustly is destroying both sales and the community that resides within.

Hello there Sandling!

What you describe sounds like "presence issues", where the system basically can't detect if you're online or not. We've been investigating a number of them--they're *very* important as you scale. And part of the frustratingness is that they're difficult to repro, but I know Lindens like Zero have been looking in-depth into the logs.

We're going to continue digging in and doing fixes as soon as possible where appropriate. Sorry about the problems.