Is this normal performance for matlab?

I am trying to plot a surface plot from a 10000x10000 matrix, however i am running into difficulties as far as performance is concerned.

Running on t6500 2.1 dual core cpu (core 2 duo) ,4gb of ram and 4gb of swap. gpu-4570 amd. running on 64 bit linux.

For testing purposes i created a random matrix and attempted to plot it as a surface plot:

R = sprand(10000,10000,0.3);

surf(R )

However i very quickly (matter of seconds) ran out of memory, after about 2 minutes ram usage was 98%, swap 100% and still no plot... Reducing to 1000x1000 matrix plots in about 3 seconds.

Is this due to my system being too slow or is it something i am doing wrong?

Thanks

Answer 1

[per isakson]

With R2012a,64bit,Win7,8GB

    R = sprand( 1000, 1000, 0.3 );
    surf( R )

crashes my Matlab. Are you sure surf is supposed to take a sparse matrix?

.

[Added 2013-03-27]

I repeated the experiment with the three different Renderers. First a copy from the "command history"

    %-- 2013-03-27 11:12 --%
    set(gcf,'renderer','zbuffer')
    R = sprand( 1000, 1000, 0.3 );
    surf( R )
    set(gcf,'renderer','opengl')
    surf( R )
    %-- 2013-03-27 11:25 --%
    set(gcf,'renderer','painters')
    R = sprand( 1000, 1000, 0.3 );
    surf( R )
    %-- 2013-03-27 11:35 --%

• with zbuffer surf( R ) worked fine
• with opengl Matlab crashed directly
• with painters surf( R ) had not displayed any result after some minutes. Cntrl+C made Matlab quit.

Restart of Matlab. Which Renderer is default?

    >> get( gcf, 'renderer' )
    ans =
    None
    >> get( gcf, 'renderermode' )
    ans =
    auto
    >> opengl info    
    Version = 3.2.0
    Vendor = NVIDIA Corporation
    Renderer = Quadro NVS 420/PCI/SSE2
    ...

[Anton]

Not sure whether it is supposed to or not (only used it since i didnt think of using A=rand(1000,1000); at the time

Just tried again,- no my matlab did not crash with

EDU>> R = sprand( 1000, 1000, 0.3 ); EDU>> surf(R )

[Anton]

Just tried again with

Q=rand(10000,10000); surf(Q)

experiencing the same issues (full swap and ram cpu@100%, yet no graph and matlab doesnt crash(although entire computer lags, bu that is expected with full ram and swap)). reducing back to 1000 works fine.

[Jan]

Which renderer do you use? OpenGL is usually more efficient for such large data, but depending on the driver, the opposite could be true.

[Anton]

Yep i am using opengl.

[per isakson]

I get the best performance with zbuffer. See my answer.

[Anton]

Thanks, sorted now.

[per isakson]

Why not tell us how you solved the problem?