Re: [JAVA3D] Multi User Server

[Scott]

I certainly won't claim to know, but I'm working on it, and  learning a few things through trial and error.  But I thought I'd join in on this to add a more specific question...   The server I've built for our MMORPG so far can easily handle (at this point) over 200 server-controlled "monster" entities, each in it's own thread, each checking for nearby players, and roaming about the terrain if nobody is around to attack.  Their thread runs every 250ms (although I'd like to get that down to every 100ms).   All client/server comms is done via TCP right now.   We've had up to 20 people connected at once with no real performance issues (in fact the CPU utilization on a dual 500Mhz PIII never passed 3%).  Each player connection also gets its own thread.  This thread handles incoming and outgoing messages, processing of the incoming messages (chat, movement, joining/authentication, disconnecting, attacking, emotes, etc).    Messages that then need to be sent to others are handled by iterating through all the nearby clients, and calling that client threads' SendMessage method.  That's a potential blocking problem I see, when a client thread is too busy handling messages handed to it from other processes, to handle it's own messages.  But, of course, the socket we need to talk to is in that thread, so we have to call that method, right? (Or course UDP might be the answer here, for low priority messages).   The server-controlled entities (monsters,NPC,etc) add messages, like moving, attacking, etc,  to be sent to all nearby players by putting messages into a queue (a Vector at this point).    Another thread handles sending these queued messages to players within range of a message origination, in a FIFO order.  That particular thread I'm having some problems with.  I need it to run all the time, or "wake up" whenver the message queue isn't empty.  If the queue _is_ empty, I want it to sleep quietly.  I've played around with thread priority, and that seems to make no difference.  I can't seem to get it to either:   1) Keep up with the message queue, so messages get stacked up and I start to drop them, according to their priority, or 2) Not have CPU utilization to jump to 100% (in which case it keeps up fine).   And note that this happens with no clients connected, so we're not blocking on socket communications...   It seems to me that message "queues" are a good way for threads to hand off a task, like processing movement messages, to another thread without holding it up., but in the first case, even when the message handler is falling behind, CPU use never passes 1% for Java.    Getting the thread queue that's processing those messages to have enough CPU time, when it's needed, to handle them as they come in, but not run at 100% CPU use is killing me...    Scott   ----- Original Message ----- From: Sharon Lin To: [EMAIL PROTECTED] Sent: Sunday, May 05, 2002 4:13 AM Subject: [JAVA3D] Multi User Server Hello all. I would like to know if you have any good tips to build a  Multi User server with good performance. What kind of socket connection to use?( DatagramPackets). What is the best way to spread users movements to other clients? Maybe sampling the position each constant time and send only the target position instead the all movements. How to treat the packets each client / server receive ? (Using 2 threads one to input and one dispatcher and writer and synchronize them using queue) . Thanks Sharon.