Simulator
The
Second Life world consists of many, interconnected, uniquely-named
simulators (also referred to as
sims or
regions)
positioned on a
Cartesian map with its origin at the
global coordinates 1000, 1000 (
Da Boom sim). A sim's global coordinates can be accessed by calling
llGetRegionCorner and dividing the results by the size of a sim (256m on a side). Neighbouring sims are connected vertically and horizontally, but never diagonally. This
grid forms the world (
image) of
SL. Sims also seem to have an
integer that represents a
group of
users for which the sim shows up on the world map (there are hidden sims; if you are in a hidden sim, all other hidden sims designated to the same group will show up on the world map).
The dimensions of a sim are unvaried: 256m x 256m. Non-physical
Objects instantly move down to 4096 meters if they go above 4097
meters on the z
axis (height) if they move after going above 768 meters. (
physical objects currently go off-world at 4096
m). Sims always have
land, although it can be completely submerged in
water. Any open space between non-adjacent sims is visibly rendered as water on the
client, but cannot be accessed (the
avatar will bounce off an invisible wall).
There is currently a limit of 15,000
primitives per sim, and approximately 100
agents. Though intended to optimize
server and client performance, these numbers are arbitrary and likely to be increased again in the future. (Initially, the limit was 10,000 prims and approximately 20 agents.)
Open-space sims (also known as void sims) have a limit of 3750
primitives per sim. A agent has to own a standard sim to get Open-space sims.
A sim keeps track of the objects and agents within it, simulates
physics, runs
scripts, and
caches and delivers object and
texture data within the sim to clients, both within ("agents") and looking into the sim ("child agents"). Sims also handle
attachments, which are really just special objects that match an avatar's
location and
rotation, and don't count against the sim's prim limit.
Simulator names are restricted to 20 characters(counting spaces) which may be split into 3 alphanumeric words.
Functions
Land |
Time |
Weather
Technical Specs
Each sim is powered by a single PC CPU core, either an , running
Debian Linux, though there may be multiple CPUs, cores, and sims per machine (1100 servers, ~2000 CPUs -
2/22/06) or
strona. There are no more than 4 sims per machine (2 dual-core CPUs per box).
Open-Space Simulators are run on the same servers as the main ones, but they are packed 4 to each CPU core.
Apparently, the sim software uses a pretty sophisticated journaling storage system (database) for objects, allowing a fast (usually) recovery with minimal data loss after a crash, power outage, etc.
"The company [
Linden Lab] also chose to store the avatars that its nearly 60,000 users [10/17/5] have created in a file system front-ended by the open-source
Apache Web server, while the open-source
Squid Web proxy cache keeps the data conveniently nearby. Metadata about the avatars is stored in an open-source
MySQL database."
Updated Specs
"Second Life has 240,000 registered users. ... Second Life currently runs on 2,579 servers that use the dual-core Opteron chip produced by AMD. Each server is responsible for an individual "sim," or 16 acres of virtual "Second Life" land. At peak usage that means that each server is handling about three users." -
Jakarta Hotel
Rumah Dijual
Rental Forklift
Properti Semarang
Parfum
Perlengkapan Bayi
GPS Tracking
Outsourcing service Indonesia
Toko Bunga
Backwall
Building Signage
Functions |
sim names