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<div dir="auto">The difference is that the OOM killer doesn't know of the pages an application allocates through the driver.
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<div dir="auto">This results in a bad decision which process to kill.</div>
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<div dir="auto">I had patches to fix this a long time ago on the list, but never found time to clean them up and push them upstream.</div>
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<div dir="auto">Andrey is now working on this, but I don't know the status of hand.</div>
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<div dir="auto">Christian.</div>
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<div class="gmail_quote">Am 29.12.2017 20:36 schrieb "Kuehling, Felix" <Felix.Kuehling@amd.com>:<br type="attribution">
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<div>Is it possible that the test is broken? A test that allocates memory to<br>
exhaustion may well trigger the OOM killer. A test can do that by using<br>
malloc. Why not by using the graphics driver? The OOM killer does what<br>
it's supposed to do, and kills the broken application.<br>
<br>
As I understand it, this change is adds artificial limitations to<br>
workaround a bug in a user mode test. However, it ends up limiting the<br>
memory available for well behaved applications, more than necessary.<br>
<br>
For compute applications that work with huge data sets, we want to be<br>
able to allocate lots of system memory. Tying available system memory to<br>
the VRAM size makes no sense for compute applications that want to work<br>
with such huge data sets.<br>
<br>
Regards,<br>
Felix<br>
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<br>
On 2017-12-15 02:09 PM, Andrey Grodzovsky wrote:<br>
> This reverts commit ba851eed895c76be0eb4260bdbeb7e26f9ccfaa2.<br>
> With that change piglit max size tests (running with -t max.*size) are causing<br>
> OOM and hard hang on my CZ with 1GB RAM.<br>
><br>
> Signed-off-by: Andrey Grodzovsky <andrey.grodzovsky@amd.com><br>
> ---<br>
> drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c | 8 +++++---<br>
> 1 file changed, 5 insertions(+), 3 deletions(-)<br>
><br>
> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c<br>
> index c307a7d..814a9c1 100644<br>
> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c<br>
> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c<br>
> @@ -1329,9 +1329,11 @@ int amdgpu_ttm_init(struct amdgpu_device *adev)<br>
> struct sysinfo si;<br>
> <br>
> si_meminfo(&si);<br>
> - gtt_size = max(AMDGPU_DEFAULT_GTT_SIZE_MB << 20,<br>
> - (uint64_t)si.totalram * si.mem_unit * 3/4);<br>
> - } else<br>
> + gtt_size = min(max((AMDGPU_DEFAULT_GTT_SIZE_MB << 20),<br>
> + adev->mc.mc_vram_size),<br>
> + ((uint64_t)si.totalram * si.mem_unit * 3/4));<br>
> + }<br>
> + else<br>
> gtt_size = (uint64_t)amdgpu_gtt_size << 20;<br>
> r = ttm_bo_init_mm(&adev->mman.bdev, TTM_PL_TT, gtt_size >> PAGE_SHIFT);<br>
> if (r) {<!-- --><br>
<br>
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