sorath

AMD Radeon OpenCL: wrong detection of memory size

Discussion created by sorath on Aug 9, 2015
Latest reply on Sep 6, 2015 by nirv_knox

Some application (Darktable or LuxMark) detect only 512 Mb of video ram insted of 1 Gb.

I have AMD Radeon HD5850 with 1 Gb of video RAM and use Debian 8 (64 bit , Jessie/stable  branch) with Catalyst 15.7 installed:

 

$ dpkg -l | grep fglrx

fglrx-atieventsd                  1:15.7-1          amd64

fglrx-control                        1:15.7-1          amd64

fglrx-driver                          1:15.7-1          amd64

fglrx-modules-dkms            1:15.7-1          amd64

glx-alternative-fglrx                  0.5.1          amd64

libfglrx:amd64                     1:15.7-1          amd64

libfglrx:i386                         1:15.7-1              i386

libfglrx-amdxvba1:amd64   1:15.7-1          amd64

libfglrx-amdxvba1:i386       1:15.7-1              i386

libgl1-fglrx-glx:amd64         1:15.7-1          amd64

libgl1-fglrx-glx:i386             1:15.7-1               i386

Also I installed opencl packages and AMD-APP_SDK-2.9-1 (in /opt):

 

$ dpkg -l | grep opencl

amd-libopencl1:amd64          1:15.7-1          amd64

amd-libopencl1:i386               1:15.7-1             i386

amd-opencl-icd:amd64          1:15.7-1          amd64

OpenCL benchamark LuxMark (LuxBall) works but show in the "Hardware Devices" section (OpenCL -> GPUs and Accelerators -> Cypress) -> "Max. Global Memory" parametr equal "524288 Kbytes" instead of ~"1 Gbytes"

 

Also on the Darktabe official site was mentioned in March 2012:

With current Radeon cards users have observed a different issue. Those cards will often only report to have less available memory than they physically own; typically 512MB out of 1GB.

clinfo output:

$ clinfo

...

Platform Version:                    OpenCL 1.2 AMD-APP (1445.5)

...

Platform Extensions:               cl_khr_icd cl_amd_event_callback cl_amd_offline_devices cl_amd_hsa

...

Max memory allocation:          134217728

...

Global memory size:               536870912

...

 

So the problem described above is still present with current OpenCL driver.

Is there the way to make OpenCL to see all video memory?

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