cudaFree leaves zero memory

After issuing a call to cudaFree I have zero memory available. Any help is appreciated.

printf("\n");
cudaMemGetInfo(&xfree,&total);
 printf("%d KB free Before cudaFree TWd  of total %d KB\n",xfree/1024,total/1024);

cudaFree( devPtrTWd );

  printf("\n");
cudaMemGetInfo(&xfree,&total);
 printf("%d KB free After cudaFree TWd  of total %d KB\n",xfree/1024,total/1024);

Here is the output.

4081283 KB free Before cudaFree TWd  of total 4194112 KB

0 KB free After cudaFree TWd  of total 0 KB