How do you determine what size you set your cache and bandwidth.

[SLtesterL2]

A few of my friends told me that these two variables can boost performance by quickening render speeds and decrease lag. Some tell me (including a Torley tutorial) to set my bandwidth to 10k while others tell me 1.5k and anything over that number is a waste of bandwidth. Some tell me to keep my cache at 512 while others tell me to max it out. I have no clue what either variable does other than cache stores the data and bandwidth streams the data to your computer but correct me if I'm wrong. So how do I determine on what numbers to set it on?

[Buttacwup Float]

You want to max your cache if you have the disk space, which most people do. The bigger your catch the less likely you need to download things a second time. Bandwidth is harder. The firestorm team suggests setting it to more than 1500 or 80% of your bandwidth which ever is lower. Wireless connections should be lower. I don't think this band width setting affects http speed. So most of what you do in SL is not limited by this throttle normally.

[Perrie Juran]

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SLtesterL2 wrote:

A few of my friends told me that these two variables can boost performance by quickening render speeds and decrease lag. Some tell me (including a Torley tutorial) to set my bandwidth to 10k while others tell me 1.5k and anything over that number is a waste of bandwidth. Some tell me to keep my cache at 512 while others tell me to max it out. I have no clue what either variable does other than cache stores the data and bandwidth streams the data to your computer but correct me if I'm wrong. So how do I determine on what numbers to set it on?

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I thought that old Torley "crank it up to the max" bandwidth video had been pulled.

Based on their experience, the Firestorm team recommend setting bandwidth at 80% of your connection speed up to a max of 1500kbps, which is the speed the SL Servers operated at.

http://wiki.phoenixviewer.com/fs_speedtest

[Nalates Urriah]

Some of the information here is out of date.

You can use SpeedTest.net to check your down & upload speeds. I suggest that you get a server IP from the viewer's Help->About... when logged in. Do a geo-locate on the IP and test to that city for an actual speed.

Consider the Max Bandwidth setting to be under 1,900. At 1,900 and above you can run into UDP protocol choking and start to have problems regardless of your connection speed. Its a server thing not a Internet speed thing. Hanging out with TPV Dev's I've learned they often use 1,500 as their max setting.

If your download speed is lower than 1,500kbps (1.5mbps) then use 80% of your measured speed.

Look at Understanding the Maximum Bandwidth Option in the Second Life™ Viewer to get an idea of how it is used and affected. That is an OLD article and things have changed. But, it is one of the best discriptions of Max Bandwidth we have.

The setting only affects how fast thngs can come into your computer and the load you place on the server. It is a setting handed to the region server to throttle it, not your computer/viewer. Settings above 1,900 or near that can cause UDP choking which is going to create probems for your viewer. The more crowded the server and the busier your connection is the more likely you are to have problems.

The best value for MaxB... experiement. But, something under 1,900.

Cache: once upon a time we had lots of rules about cache size and how often to clear it. That changed a couple of years ago when the cache was redesigned. There is still lots of old misinformation from those days floating around.

Clearning cache used to be a first step in any troubleshooting effort. Now it is an absolute last resort step. In fact clearning the cache aggrivates many of the problems we see now, like inventory failing to completely load. Anyone that tells you start by clearing the cache likely is out of date in their troubleshooting techniques. One only clears cache as a last resort or when they know there is a very high probablity it is corrupt.

Few understand that with inventory problems clearing the entire cache is a dumb thing to do. But it is easy to tell people to do that. It is possible to clear the inventory's cached list without clearing the entire cache, which is the smart way to troubleshoot inventory problems. Because, if it is a connection problem, reloading the entire cache aggrivates the inventory problem.

Much of the connection to SL used to be via the UDP protocol. It was prone to corruption. Now most communication is via HTTP, which has built in eror correction. Coruption is way way less a problem, thus the change in troubleshooting proceedure.

Some support groups tell you to turn off HTTP get Texture or Inventory. That is a step to determine if you have a connection problem of some kind. HTTP is better, safer - as  in fewer problems, and genrally faster. Keep it on unless you know you have an HTTP related problem or are troubleshooting.

In the old cache it took longer to find files in a large cache. So, smaller was thought good. The viewer was dependint on your computer to find the file. And when the cache filled up, they were smaller then, things got really slow as the viewer used your computer's system to find and delete old files.

With the current cache the viewer indexes cached files. Finding files and locating old files to delete, is way faster. So, we can have much larger caches. Since disks are cheap, new WD Black label 1tb drives go for $50-$75 on eBay, and fast there is no reason not to max out the cache. The new SSD drives are even better for large caches.

Unfortunately, the caching system in the viewer is not that great. If you use Ctrl-Alt-3 (a toggle), you can see if textures are being retrived from the cache or downloaded. I generally login to my SL home. The viewer downlaods numerious textures from my home region every time. I know they are in the cache, but it does it anyway. The Lindens are going to take another look at caching soon because it is so lame.

So the best size for a cache... It is hard to say what is best. I set mine to 4gb. Today my cache has 442mb of stuff in it and I've been shopping/exploring lately. So, it should be big. 442mb doesn't seem that big to me...

Set it to something large and then watch your cache to see if it is filling up. I understand there is some multi-threading in the cache code so deleting files should not slow you down, but a  large cache that isn't filling up would avoid any possible slow down.

You can check cache size by looking at the folder: C:\Users\[Win_login_ID]\AppData\Local\SecondLife (Vista/Win7/8).