Strategies for keeping a sim as lag free as possible

I'm considering buying a private island, one that would be used primarily for shopping and I wondered if people could share their ideas, assumptions, myths about how to keep a sim relatively lag free. Mostly, I'm interested in hearing about building methods and reasonable restrictions on rented vendor stalls.

Three things are the top causes of sim lag:

1) AVs.
2) Textures.
3) Scritps.

Malls are huge sources of all three. You WANT AVs to shop there, but don't make it worse by putting in camping chairs or camping poseballs if you really care about lag.

For the other two make sure people use LOW LAG vendors. A single vendor can be a single script and a couple textures or it can be 30 scripts and 30 textures. Which one will you want 150 of in your sim?

Spread out the shopping areas and make sveral smaller enclosed buildings, some even in the sky and keep them seperated. This doesn't just help the client lag but preventing an entire sims worth of textures loading every time someone tps in and out will help sim lag considerably.

A lot of that may restrict the design of what people ussualy want which is an open area with everything visiable from everywhere, but... that's the trade off. Keep those three things down as low as possible and your sim will be as lag free as possible.

If you're going to use the whole island for shopping, get a low-lag transport system (copiable), and use the full thrid dimention availible in SL. Most forget you can build UP. You have 768m of building hieght. Most people set thier draw distance to @96m (those who set high have the machines to render high textured areas anyway), so set mall levels every 100m or so. Keep the TP point into the sim clear as possible of anything (textures/scripts) that will cause them to fail TP or to take forever to rez. I'd suggest a map to the mall, with directions on how to use the TPer (newbies have a hard enough time walking, let alone using TPers *Grins*). This will let the Main Floor be relitively lag free....and would also be a Premium vendor spot, but come with the pricetag to match, and rules and regs to maintain the low lag level.

Good luck ^.^
~Jessy

I am under the impression that as far as prims and textures goes, things you don't see it's not downloaded to the client.

However presistence sripts, worst of all poorly scripted vendor with active listen all the time are the one of the usual cause. Also make sure all effects type objects/ particles/ sounds... have time out shut off.

There isn't much you can do with Avs related lag.... ok maybe one thing you can do is not to put camping devices on the island.

I'd like to add;
Even though waterfalls and fountains make for pretty scenery, the scripts used in them for movement and effects can really be a burden.

I would think sound (water sounds...etc) plays a part in lag as well. Can anyone confirm this?

Try and minimise the amount of textures you use i.e. if your building a mall try using the same textures for all of your buildings and spaces rather than creating differently textured spaces for each vendor. Also make sure that none of your textures exceed a resolution of 512 x 512 and if possible keep the resolution lower. Also try and use basic shapes like cubes and cylinders etc rather than torus as these will rez allot faster. Also you can impose restrictions on the people who rent your spaces to stop them using high resolution textures, particle scripts etc.

Does this mean that all scripts are not created equally? I knew that the ones that are set to actively listen on the chat channel were bad news. Besides, who wants to talk to their shoes in public to turn off the bling? But is there a comprehensive guide anywhere to what kinds of scripts are bad news? I hate to think I'm lagging down my sim because I like pretty lights and water effects, while I'm sitting there thinking it's not my fault because each thing that runs only has one script and it's not set to active listen.

Particles and texture animations need a script to initialize them but the script does not need to continue to run after that if there is no other work that needs to be done. And yes... LSL is so lame that "dead" scripts continue to take up SIM CPU even though they are clearly never going to process another event ever again.

So if you are the builder, put in the following line after the particle or texture animation initialization:
llSetScriptState(llGetScriptName(), FALSE);

This will actually stop the scropt from running after it has done its work.

Or manually stop the sript from running after you have started it. The state of the particle effect and the texture animation will survive regeon restarts and even putting into and taking out of inventory!

I removed 1/2 the scripts from my sim and lowered the script time from 16ms down to 8ms with this simple trick.

Also even if you bought the object you can try to turn off all scripts in the object from the tools menu. Depending on exactly the permissions of the object you can do this even if you can't edit the script. If the entire object is no mod then you can't

SO yes you can have a sim full of moving water, waterfalls, fires and everything else and not have a single script running if you wish!

I'm going to try this script line when I get back in-world tonight! Thanks! As a beginning builder/seller, I want to contribute to SL in a positive way and not lag down the world with my stuff!

All scripts are NOT created equal!

Open listens are just one of many, many practices that can lead to lag. It's the primary offender, I expect.

It would be nice to have a good way of measuring a script's CPU usage. What would be really cool is an underwriters' lab that tests scripts and rates them for efficiency, and then gives a rating or seal of approval.

All scripts are certainly NOT created equal. Island owners have access to a special Estate Manager which lets you do things like list all the active scripts in the sim and sort them in order of how much processing time they're taking up (less is better).

In my sim, I was shocked to find that the biggest resource-hog script on the island was the root prim of my house! The house comes in multiple parts and uses this 'rez faux'-type system that makes positioning easier. But the house is sitting where I want it now, and there's no need for any script to run, and yet it's the most active script I've currently got!

A lot of items (even a lot of individual prims) actually contain multiple scripts that run simultaneously, and depending on how those scripts are written, they can really compound problems. I have a friend who designs color-changing furniture. Her pieces are all at the top of my busiest-scripts list, and I believe it's because she's using listeners in all the color-changing prims instead of using link messages. Link messages still require extra scripts in each color-changing prim, but they're supposedly less intensive than listeners.

EDIT: Also, when thinking about lag, remember it's not just the sim you have to worry about. Not everyone has an awesome computer, and huge textures not only result in more download time, but affect your PCs ability to display everything. Club lighting is also notorious for causing lag for a number of reasons.

Right, farrallon, not to mention all the scripts that are sitting around that did something that never needs to be done again, like setting floating text or a constant particle system, when the script could halt or even delete itself.

As a scripter who does a little jewerly work, I often get exclamations from folks who say "I took the bling script out and it keeps blinging!" This from folks making jewerly, or whatever. I teach them the simple trick of a script that gives the effect you want and then deletes itself. Want to change the effect? Mod the script and drag it in again.

It would be good if SL could notice when a script no longer has any event handlers, in which case it could be deleted from the interpreter.

Normally when you rez a build using rez faux it will give you the option to 'save' once you have finished positioning the build. Click save and that will delete all of the positioning scripts from the root prims.

Yeah, this was not the actual Rez Faux, but a similar system. I was expecting that sort of shut-down thingy too, but there was no such ability with this house.

I add: DONT USE POSEBALLS for simple seats. Especially poseballs which listen. Use SitTargted seats instead. They may difficult to target but they work great and are lag-free. SitTarget is a property of prim. It is set by script but the script is no longer needed once run. Exemple code:

on_rez(integer arg) {
        vector sitOffset = <0.3, 0.0, 0.4>;
        vector sitEulrot = <0.0, 0.0, 0.0>;
        sitEulrot *= DEG_TO_RAD;
        rotation sitRotation  = llEuler2Rot(sitEulrot);;
        llSitTarget( sitOffset, sitRotation);
        llOwnerSay("sit target setted");
        llRemoveInventory(llGetScriptName()); // Delete self
    }

Poseballs aren't generally laggy. They show up as top scripts often because they inherit the monster MS times of the avatars that are sat on them.

You haven't seen script times until a pair of cyber-goth subs with full scripted collars, cuffs, double active shields, vampire accessories and twin desert eagles decide to salsa

Search this forum for "easy sit target" to find the totally painless way to set a sit target.

I was a resident on One sim that had an almost permanant Lag Pocket in it. An area about fifty Five meters square in the North West portion of the Sim. It was there from day One, and Nothing would reduce it. We never determined a Cause. The sim has been sold Twice since then, and as far as i Know, that region is Still a lag Pocket. You can do everything right, and still get Lag.

Angel.