Needed: Spot sim performance "barometer"

Doing comparative evaluations of several whole-sim player towns, I've experienced big differences in lag or time-dilation. I'd like to provide some objective, quantitative measure but don't know of a tool or link to measure the performance of a particular sim on a particular day or time.

These are sims I do not control, so I can't install some persistent meter. Is there one that I can pull out, and read the ambient performance like a thermometer or a barometer?

Yo! control-shift-1 brings up the sim's stats (see attached pic). Several of the metrics there are useful for diagnosing sim performance.

The wiser heads in here can correct and expand on this, but as far as I understand it:

Sim FPS: the number of times per second the sim state updates itself. 45=good, 0 = less good
Physics FPS: ditto for the physics engine specifically. make some chain links, enable physics, watch this drop like a stone (sorry guys in Cordova for learning that the hard way!)

Packet loss: how's your connection doing?

Objects: as this approaches 15000, maybe sim performance drops, certainly client performance drops if you're rendering a large proportion of those prims

Active Scripts: more scripts equals more load on the sim, though this varies heavily with the nature and the quality of the scripting involved

Script perf: the number of instructions per second the sim is currently managing. I dunno if higher or lower is better. Nathan stewart explained it to me on #secondlife, but I went crosseyed. =D

Kage, many thanks. Just what I needed.

Anyone, what's the difference between "Basic FPS," which I found to dynamically flutter between 10-15 fps with transient drops in the sims I visited, and the "Sim FPS" which seemed to be a static 45 fps in the two I visited with the <ctl><shift>1 engaged?

yus, basic fps is clientside and highly dynamic based on how many particles, shiny, locally lit objects you're rendering, etc. The other one is how many updates the server is able to manage per second, and should hopefully be pegged at 45 or so.

Whoa there, this is an interesting definition. Are you sure about this?
So, if I want to change something in 50 prims "at once" it will necessarily take more than a second to do?

Warning: Active Scripts was changed from a count to an FPS value in 1.7. Just FYI. I freaked out when they changed that since there were only 50-some active scripts in the sim at the time.


Active Objects, however, still reports a fair estimate of this number. For now...

Good. The wiser heads are now correcting and expanding on this. =D

Eggy: My apologies for being inarticulate; I meant to intimate (my basic and likely inaccurate understanding) that the server FPS rating is how many state updates the server is able to push to clients per second. Within each frame, the server is able to process many multiple object, script, and physics updates. That's how it was explained to me, but this is a good discussion; if my understanding needs correction, here's a great place to do it.

Jeffrey: Thankee for the clarification!

nah, Kage, you got it

There's some more info on the stats available in the wiki. There is a sticky with a link to it in the technical forum.
http://secondlife.com/tiki/tiki-index.php?page=How+do+I+read+the+sim+performance+stats%3F