Only 300 MB of free memory on Tesla S2050 GPUs

Accelerated Computing CUDA CUDA Programming and Performance
1

I have a Tesla S2050 with driver version 260.19.26 installed. Each of the GPUs is supposed to have 3GB of global memory and that’s what deviceQuery tells me too.

However, when I run a simple program that calls cudaMemGetInfo (see code snippet below), I find that only 307757056 (~300 MB) of the 2817982464 bytes are “free”. I get the same result for all 4 GPUs. No other jobs are running on my GPUs.

For example, I bump into this memory issue also when I try running the SDK’s FDTD3d example:

fdtdGPU…
cudaGetDeviceCount
cudaSetDevice (device 0)
cudaMalloc bufferOut
cudaMalloc bufferIn

!!! Error # 0 at cudaMalloc ‘out of memory’.
GPU FDTD loop

fdtdGPU complete

FAILED

!!! Error # 0 at line 44 , in file src/FDTD3d.cpp !!!

Exiting…

However when I run the corresponding example in OpenCL, the code runs just fine. So is this a driver problem?

Thanks in advance,
Mark

==============NVSMI LOG==============

Timestamp : Mon Jan 10 14:06:30 2011

Driver Version : 260.19.26

Unit 0:
Product Name : NVIDIA Tesla S2050
Product ID : 920-20804-0020
Serial Number : 0383110000030
Firmware Ver : 6.2
Intake Temperature : 26 C
GPU 0:
Product Name : Tesla S2050
Serial : 0322810019679
PCI Device/Vendor ID : 6de10de
PCI Location ID : 1:7:0
Bridge Port : 0
Temperature : 47 C
Utilization :
GPU : 0%
Memory : 0%
Volatile ECC errors:
Single Bit :
FB : 0
RF : 0
L1 : 0
L2 : 0
Total : 0
Double Bit :
FB : 0
RF : 0
L1 : 0
L2 : 0
Total : 0
Aggregate ECC errors:
Single Bit :
Total : 0
Double Bit :
Total : 510203

… same for the other 3 GPUs…

----- Mem check code -------
#include
#include <cuda_runtime.h>

int main(int argc, char** argv)
{
cudaSetDevice(0);
size_t freeMem, totalMem;
int a;
a = cudaMemGetInfo(&freeMem, &totalMem);
printf(“Free = %lu, Total = %lu, error = %i\n”, (unsigned long)freeMem, (unsigned long)totalMem, a);
return 0;
}

2

It works fine for me with 260.19.21.

cat /proc/driver/nvidia/version

NVRM version: NVIDIA UNIX x86_64 Kernel Module 260.19.21 Thu Nov 4 21:16:27 PDT 2010

GCC version: gcc version 4.1.2 20080704 (Red Hat 4.1.2-44)

Could you try with the following code?

// Compile with gcc check_mem.c  -I/usr/local/cuda/include -lcuda

#include <cuda.h>

#include <stdio.h>

static unsigned long inKB(unsigned long bytes)

   { return bytes/1024; }

static unsigned long inMB(unsigned long bytes)

   { return bytes/(1024*1024); }

static void printStats(unsigned long free, unsigned long total)

   {

      printf("^^^^ Free : %lu bytes (%lu KB) (%lu MB)\n", free, inKB(free), inMB(free));

      printf("^^^^ Total: %lu bytes (%lu KB) (%lu MB)\n", total, inKB(total), inMB(total));

      printf("^^^^ %f%% free, %f%% used\n", 100.0*free/(double)total, 100.0*(total - free)/(double)total);

   }

int main(int argc, char **argv)

   {

      size_t free, total;

      int gpuCount, i;

      CUresult res;

      CUdevice dev;

      CUcontext ctx;

      char name[100];

CUresult e = cuInit(0);

cuDeviceGetCount(&gpuCount);

      printf("Detected %d GPU\n",gpuCount);

for (i=0; i<gpuCount; i++)

      {

      cuDeviceGet(&dev,i);

      cuDeviceGetName(name,100,dev);

      cuCtxCreate(&ctx, 0, dev);

      res = cuMemGetInfo(&free, &total);

      if(res != CUDA_SUCCESS) printf("!!!! cuMemGetInfo failed! (status = %x)", res);

      printf("^^^^ Device: %d %s\n",i,name);

      printStats(free, total);

      cuCtxDetach(ctx);

      }

return 0;

   }

and I am getting the correct output:

This is on a node with 1 M2050 (ECC OFF) and 1 S2050 (ECC ON)

Detected 5 GPU

^^^^ Device: 0 Tesla M2050

^^^^ Free : 2937323520 bytes (2868480 KB) (2801 MB)

^^^^ Total: 3220897792 bytes (3145408 KB) (3071 MB)

^^^^ 91.195800% free, 8.804200% used

^^^^ Device: 1 Tesla S2050

^^^^ Free : 2534932480 bytes (2475520 KB) (2417 MB)

^^^^ Total: 2817982464 bytes (2751936 KB) (2687 MB)

^^^^ 89.955580% free, 10.044420% used

^^^^ Device: 2 Tesla S2050

^^^^ Free : 2534932480 bytes (2475520 KB) (2417 MB)

^^^^ Total: 2817982464 bytes (2751936 KB) (2687 MB)

^^^^ 89.955580% free, 10.044420% used

^^^^ Device: 3 Tesla S2050

^^^^ Free : 2534932480 bytes (2475520 KB) (2417 MB)

^^^^ Total: 2817982464 bytes (2751936 KB) (2687 MB)

^^^^ 89.955580% free, 10.044420% used

^^^^ Device: 4 Tesla S2050

^^^^ Free : 2534932480 bytes (2475520 KB) (2417 MB)

^^^^ Total: 2817982464 bytes (2751936 KB) (2687 MB)

^^^^ 89.955580% free, 10.044420% used

3

Actually I with 260.19.21 I had the exact same problem. Anyway I ran your code and got this

Detected 4 GPU
^^^^ Device: 0 Tesla S2050
^^^^ Free : 307757056 bytes (300544 KB) (293 MB)
^^^^ Total: 2817982464 bytes (2751936 KB) (2687 MB)
^^^^ 10.921184% free, 89.078816% used
^^^^ Device: 1 Tesla S2050
^^^^ Free : 307757056 bytes (300544 KB) (293 MB)
^^^^ Total: 2817982464 bytes (2751936 KB) (2687 MB)
^^^^ 10.921184% free, 89.078816% used
^^^^ Device: 2 Tesla S2050
^^^^ Free : 307757056 bytes (300544 KB) (293 MB)
^^^^ Total: 2817982464 bytes (2751936 KB) (2687 MB)
^^^^ 10.921184% free, 89.078816% used
^^^^ Device: 3 Tesla S2050
^^^^ Free : 307757056 bytes (300544 KB) (293 MB)
^^^^ Total: 2817982464 bytes (2751936 KB) (2687 MB)
^^^^ 10.921184% free, 89.078816% used

Is there any command that I should use to configure the GPUs before running SDK examples or any CUDA code for that matter?

Thanks for looking into this.

Cheers,
Mark

4

You should not need any additional commands, loading the driver and creating the /dev/nvidia* files as documented in the release notes should be enough.

Which OS are you running?

5

This is the OS installed on the machine.

SUSE Linux Enterprise Server 11 (x86_64)

VERSION = 11

PATCHLEVEL = 1

output from “uname -a”:

Linux ultra 2.6.32.19-0.3.1.1982.2.PTF-default #1 SMP 2010-09-17 20:28:21 +0200 x86_64 x86_64 x86_64 GNU/Linux

Thanks,

Mark

6

What is the output of cat /proc/driver/nvidia/version?

I don’t have a SLES machine.
If you are a registered developer, please file a bug. If you are not, please apply to become one.

7

I just filed a bug report (incident #779166).

Cheers,

Mark