这两块卡难道 OpenCL 性能一样吗？

[fanzeling1314]

有两块卡，一块是笔记本上的 HD8000系列，一块是 R9 270X ，按理说两块卡的性能应该差异很大 才对。但我感觉程序在两块卡上跑起来速度差不多啊。 用clinfo 查看一下，发现大部分参数完全一样，只是GPU主频高点，难道就这点差别？废话不多说 上图：

R9 270X GPU-Z 截图[




HD8000 GPU-Z 截图[



R9 270X CLINFO 信息
Device Type: CL_DEVICE_TYPE_GPU
Device ID: 4098
Board name: AMD Radeon R9 200 Series
Max compute units: 20
Max work items dimensions: 3
Max work items[0]: 256
Max work items[1]: 256
Max work items[2]: 256
Max work group size: 256
Preferred vector width char: 4
Preferred vector width short: 2
Preferred vector width int: 1
Preferred vector width long: 1
Preferred vector width float: 1
Preferred vector width double: 1
Native vector width char: 4
Native vector width short: 2
Native vector width int: 1
Native vector width long: 1
Native vector width float: 1
Native vector width double: 1
Max clock frequency: 1100Mhz
Address bits: 32
Max memory allocation: 536870912
Image support: Yes
Max number of images read arguments: 128
Max number of images write arguments: 8
Max image 2D width: 16384
Max image 2D height: 16384
Max image 3D width: 2048
Max image 3D height: 2048
Max image 3D depth: 2048
Max samplers within kernel: 16
Max size of kernel argument: 1024
Alignment (bits) of base address: 2048
Minimum alignment (bytes) for any datatype: 128
Single precision floating point capability
Denorms: No
Quiet NaNs: Yes
Round to nearest even: Yes
Round to zero: Yes
Round to +ve and infinity: Yes
IEEE754-2008 fused multiply-add: Yes
Cache type: Read/Write
Cache line size: 64
Cache size: 16384
Global memory size: 2147483648
Constant buffer size: 65536
Max number of constant args: 8
Local memory type: Scratchpad
Local memory size: 32768
Kernel Preferred work group size multiple: 64
Error correction support: 0
Unified memory for Host and Device: 0
Profiling timer resolution: 1
Device endianess: Little
Available: Yes
Compiler available: Yes
Execution capabilities:
Execute OpenCL kernels: Yes
Execute native function: No



HD 8000 CLINFO 信息


Device Type: CL_DEVICE_TYPE_GPU
Device ID: 4098
Board name: AMD Radeon HD 8600/8700M
Max compute units: 6
Max work items dimensions: 3
Max work items[0]: 256
Max work items[1]: 256
Max work items[2]: 256
Max work group size: 256
Preferred vector width char: 4
Preferred vector width short: 2
Preferred vector width int: 1
Preferred vector width long: 1
Preferred vector width float: 1
Preferred vector width double: 1
Native vector width char: 4
Native vector width short: 2
Native vector width int: 1
Native vector width long: 1
Native vector width float: 1
Native vector width double: 1
Max clock frequency: 825Mhz
Address bits: 32
Max memory allocation: 1073741824
Image support: Yes
Max number of images read arguments: 128
Max number of images write arguments: 8
Max image 2D width: 16384
Max image 2D height: 16384
Max image 3D width: 2048
Max image 3D height: 2048
Max image 3D depth: 2048
Max samplers within kernel: 16
Max size of kernel argument: 1024
Alignment (bits) of base address: 2048
Minimum alignment (bytes) for any datatype: 128
Single precision floating point capability
Denorms: No
Quiet NaNs: Yes
Round to nearest even: Yes
Round to zero: Yes
Round to +ve and infinity: Yes
IEEE754-2008 fused multiply-add: Yes
Cache type: Read/Write
Cache line size: 64
Cache size: 16384
Global memory size: 2147483648
Constant buffer size: 65536
Max number of constant args: 8
Local memory type: Scratchpad
Local memory size: 32768
Kernel Preferred work group size multiple: 64
Error correction support: 0
Unified memory for Host and Device: 0
Profiling timer resolution: 1
Device endianess: Little
Available: Yes
Compiler available: Yes
Execution capabilities:
Execute OpenCL kernels: Yes
Execute native function: No

[fronteer]

R270 的计算单元数是 20, Radeon 8000 的计算单元数是 6 ， 差别很大啊， 你需要找一个OpenCL 计算类型的应用测试一下， 如 AMD SDK 下面的例子.

[outstander]

引用 1 楼 fronteer 的回复:

R270 的计算单元数是 20, Radeon 8000 的计算单元数是 6 ， 差别很大啊， 你需要找一个OpenCL 计算类型的应用测试一下， 如 AMD SDK 下面的例子.

正解，核心数和计算单元数是GPU的重要指标

[qinlj0]

区别不大证明Open CL直接用的就是主CPU进行的计算。 骗子不会这么懒吧？搞个板载CPU都懒得动弹？难怪一个接一个败仗。