[Beignet] Graphical Glitches and Local Memory Performance Issue

[Artyom Beilis]

Hello,

I'm trying to use Beignet driver to use OpenCL:

I have tested in on two platforms:

Platform #1  i5-3470 with Intel® HD Graphics 2500
--------------------------------------------------------------------------

Some of clinfo output:

  Platform Profile:                              FULL_PROFILE
  Platform Version:                              OpenCL 1.2 beignet 1.3
  Platform Name:                                 Intel Gen OCL Driver
  Platform Vendor:                               Intel
  ...
  Local memory type:                             Global
  Local memory size:                             65536
  ...
  Unified memory for Host and Device:            1
  ...
  Name:                                          Intel(R) HD Graphics
IvyBridge GT1
  Vendor:                                        Intel
  Device OpenCL C version:                       OpenCL C 1.2 beignet 1.3
  Driver version:                                1.3

I tested both beignet 1.2.1 and now recent 1.3 using Linux 4.4

The biggest issue is immediate graphical glitches I get when I start
an OpenCL program
including clinfo. So even when computation complete fine the GUI
becomes unusable until reboot.

-------------------------------------------------------------
Platform #2  i5-6600 with Intel® HD Graphics 530

Works OK but significantly slower than using same GPU under Windows
with Intel OpenCL drivers.

The biggest hit that I see in profiling comes from reduction - use of
local memory is very slow:
I see same:
  -----------
  Local memory type:                             Global
  --------

On beignet 1.2.1 - using Global memory for local simulation gives
significant performance reduction and makes the performance mush
slower for comparable CPU implementation

On Windows OpenCL implementation I see that the Local memory type is
Local and performance is much better.

Question:

1. Is there any fix for graphical glitches that occur?
2. Is there a way to enable Local memory support as LOCAL memory and not Global.


Thanks,
   Artyom