Hi Mike,
Thank you for getting back to me and apologies for not including the OS
in my original message - the OS is Windows XP.
I have just tried the server on a Fedora Linux box (the CPU is very
roughly about 30% slower than on the XP box) and unfortunately the load
average is about 2.0 whilst the %CPU for the java process is at about
70%. I don't know if that helps to provide any clues or not.
Many thanks,
Richard.
--
Michael Grundvig wrote:
What OS are you using? CPU usage with sockets is MUCH higher on
windows then Linux for instance.
Mike
----- Original Message ----- From: "Richard Lowe" <[EMAIL PROTECTED]>
To: <[email protected]>
Sent: Thursday, April 19, 2007 9:14 AM
Subject: 1000+ simultaneous connections with data transfer?
Hi All,
I am using Mina 1.0.0 under JRE 1.4.2 and testing it using a simple
server and client program that I have written. I must say that Mina
is excellent, the API is very easy to work with. I have a
performance question and am hoping that you guys might be able to
supply me with an answer.
My server program starts up and waits for connections on a
predesignated TCP port (I use a class that extends IOHandlerAdapter
to send events to my server thread). Every 1/4 of a second it will
write ~ 128 bytes of data to every connected session if the
connection is a new session *or* the session has successfully
responded to a previous 128 byte packet with a 64 byte packet of its
own. I use the following tweaks to help improve performance:
ByteBuffer.setAllocator(new SimpleByteBufferAllocator());
ByteBuffer.setUseDirectBuffers(false);
My client program (running on a seperate machine) creates 1000
instances of an IoHandlerAdapter. Every time it receives a 128 byte
packet from the server, it immediately responds with a 64 byte packet.
To summarise, I'm sending 128 bytes per session every 1/4 of a second
to which I am receiving 64 bytes back.
The test 'server' (more accurately desktop) is an AMD Athlon 3200+
(so not the most powerful) and I am getting around 75% CPU
utilisation with 1000 connections.
More specifically:
100: 4%, 200: 10%, 300: 22%, 400: 38%, 500: 43%, 600: 58%, 700: 65%,
800: 66%, 900: 70%, 1000: 75%
The bottleneck seems to be in the Mina layer or below. Is the
performance above what you would consider to be 'optimal' or is there
an obvious way of substantially reducing CPU load?
Ideally I would love to support 2000+ simultaneous connections on
this test machine. Is there a way of achieving this without my CPU
fan flying off it's spindle and my machine setting alight?
Any advice that you can offer would be very much appreciated!
Cheers,
Richard.
