Re: 1000+ simultaneous connections with data transfer?

[Michael Grundvig <mi...@electrotank.com>]

What OS are you using? CPU usage with sockets is MUCH higher on windows then 
Linux for instance.

Mike

----- Original Message ----- 
From: "Richard Lowe" <mi...@webcogs.com>
To: <de...@mina.apache.org>
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. 

Re: 1000+ simultaneous connections with data transfer?

[Richard Lowe <mi...@webcogs.com>]

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" <mi...@webcogs.com>
> To: <de...@mina.apache.org>
> 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. 
>