How to Check if a Sim is Class 4 or Class 5 in Second Life

“All our sims are Class 5!” is a common line in the ads of SL real estate businesses, but what does it mean? Is there a way to check the class of a sim for yourself? Does the class even matter?

Sims (also called regions) are squares of land simulated by software running on Linden Lab’s servers. For full sims, there are as many as four sims being simulated by each server. From time to time, Linden Lab switches to more modern servers but they keep the old servers around. The latest upgrade happened in November 2006, when Linden Lab switched from class 4 to class 5 servers. All new sims bought since December 2006 are on class 5 servers. There is no class 6 (yet).

Here’s a table summarizing the main differences between class 4 and class 5 servers:

	Class 4	Class 5
Monthly cost	195 USD/mo.	295 USD/mo.
Memory	2 GB	4 GB
Power Consumption	230 Watts	175 Watts
Power Supply Efficiency	67%	84%
Hardware	AMD Opteron 270	Intel Xeon 5148
SATA Disk	slower	faster
System Fans	smaller	bigger

People who own a sim on a class 4 server can keep it class 4 and continue paying 195 USD/mo. That’s why they haven’t all upgraded to class 5. It is possible to upgrade from class 4 to 5, if you’re willing to pay Linden Lab 100 USD — yet another reason not to upgrade.

If you own a sim, you can check the class of the server it’s on by logging into your SL account at secondlife.com and going into the Land Manager section. But that’s of no use to renters or buyers who don’t own the sim.

I looked for a way to check the server class without being the sim owner and found two:

1. While logged in, go to the top menu > Help > About Second Life, and look for a line that says something like sim1234.agni.lindenlab.com. The number (1234 in this case) tells you if it’s class 4 or class 5. Originally, the class 5 servers were numbered 2120 and above. In May 2008, Prospero Linden wrote a blog post indicating that indicated the class 5 servers started at 2133. (Maybe 2120 through 2132 all got upgraded to class 5, making 2133 the lowest-numbered class 5?)
2. There’s a HUD tool being sold on XStreet that can tell you the class of the sim you’re currently in. I tested it on some sims where I know the server class and it got the right answer in all cases.

I’ve gotten feedback from people saying that neither of the above two methods is to be trusted. I happen to know Prospero, so I asked him and he said that when he left Linden Lab in May 2009, method 1 was still accurate and he suspects it’s still accurate. Moreover, he noted that all mainland sims are class 5 and the number of class 4 sims is only in the hundreds (out of about 23,000 private sims — so at most 4% of all private sims are class 4). Also, if you know that a real estate business started after December 2006, then you can be pretty sure all their sims are class 5.

Does the server class even matter? Debates rage on the forums. All you should really care about is whether the sim in question is laggy or not. A class 5 sim loaded with scripts and avatars might be laggier than an empty class 4 sim. You can check lag with things like the lag meter and the statistics bar. The SL wiki also has a great page on lag in general. Lastly, a sim owner can do a lot to improve sim performance regardless of server class; there’s a great article on that in the SL wiki.

The bottom line is that the server class is only one factor out of many factors that affect the lag in a sim. A Porsche won’t run very well if it’s buried in glue.

Update - November 2009

On November 10, 2009, Jack Linden wrote a post on the official Second Life blog saying that:

• there were 2000 class 4 sims remaining at that time (which is probably a rough estimate),
• Linden Lab would be upgrading all class 4 sims to class 5 over the coming few months (so by the end of February 2010),
• the “class” label / designation would no longer be used, and
• everyone will get a minimum “hardware specification” which might vary from server to server (but there will be a lower bound).

Update - October 2010

There’s a website called Second Life Grid Survery at gridsurvey.com which keeps track of the “server class” of every sim in Second Life. Just find the sim you’re curious about and scan through the web page full of information about it. (They use a bot to survey SL sims on a regular basis.)

Update - July 2011

It seems the grid now has “class 7” sims as well (in addition to class 5, but no class 6?). I’m not sure when class 7 sims started appearing.

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Photo Credits: porsche carrera gt by Axion23 on Flickr. Porsche 911 Carrera 4S by Bryn Pinzgauer on Flickr. Both photos are licensed under a Creative Commons Attribution 2.0 license.

Comments

[Mike Johnson - Realtor]

Tracking Second Life has been a hobby of mine for a while now, so I always enjoy picking up knowledge from posts like this. More than once I've considered turning my knowledge of real estate into a Second Life career. In one sense, it feels so cerebral, so removed from authentic human transactions, and then another part of me thinks that's just a false dichotomy, the creation of two categories where only one exists.