0 Replies Latest reply on Sep 6, 2012 2:44 AM by anu9anna

    FFT Sample code performance on CPU and GPU

    anu9anna

      Hi,

       

                I am using AMD Radeon HD 6770 Graphics Card and installed AMD SDKv2.7 & Catalyst Driver12.8 on RHEL6.0 . While running the "FFT" sample program on cpu device (Intel Core2 Duo)  and gpu device with timing option , on cpu device the program is running faster than on gpu .

       

       

      [root@localhost x86]# ./FFT -t

      Platform 0 : Advanced Micro Devices, Inc.

       

      Original Input Real

      15.3732 201.81 51.9855 89.2322 92.572 34.4675 96.2478 66.3863 11.345 225.168

       

       

      Original Input Img

      0.0600514 0.788318 0.203068 0.348563 0.361609 0.134639 0.375968 0.259322 0.0443163 0.879562

       

      Platform found : Advanced Micro Devices, Inc.

       

      Selected Platform Vendor : Advanced Micro Devices, Inc.

      Device 0 : Juniper Device ID is 0x9bee888

      Build Options are : -x clc++

      Executing kernel for 1 iterations

      -------------------------------------------

       

      Output real

      131643 -1085.95 -997.15 -1791.52 532.118 1659.74 -166.271 969.692 1189.76 -862.707

       

       

      Output img

      514.23 2289.84 936.489 -603.839 699.7 1018.18 1900.06 795.439 -1328.03 -293.334

       

      Length                   Time(sec)                [Transfer+Kernel]Time(sec)

      26214400                 0.932                    0.492                   

       

       

      And with CPU ,

       

       

      [root@localhost x86]# ./FFT -t --device cpu

      Platform 0 : Advanced Micro Devices, Inc.

       

      Original Input Real

      15.3732 201.81 51.9855 89.2322 92.572 34.4675 96.2478 66.3863 11.345 225.168

       

       

      Original Input Img

      0.0600514 0.788318 0.203068 0.348563 0.361609 0.134639 0.375968 0.259322 0.0443163 0.879562

       

      Platform found : Advanced Micro Devices, Inc.

       

      Selected Platform Vendor : Advanced Micro Devices, Inc.

      Device 0 : Intel(R) Core(TM)2 Duo CPU     E7500  @ 2.93GHz Device ID is 0x8d62ab8

      Build Options are : -x clc++

      Executing kernel for 1 iterations

      -------------------------------------------

       

      Output real

      131643 -1085.95 -997.15 -1791.52 532.119 1659.74 -166.27 969.692 1189.76 -862.707

       

       

      Output img

      514.23 2289.84 936.49 -603.839 699.7 1018.18 1900.06 795.439 -1328.03 -293.334

       

      Length                   Time(sec)                [Transfer+Kernel]Time(sec)

      26214400                 0.695                    0.294          

       

       

          

      How can I increase performance with GPU ?

       

       

       

      Thanks