[Numpy-discussion] Numpy 1.11.0rc1 released.

[Christoph Gohlke]

On 2/23/2016 1:05 PM, Pauli Virtanen wrote:
> 23.02.2016, 22:40, Charles R Harris kirjoitti:
> [clip]
>> On all 32-bit platforms:
>>
>> ============================================================
>> ERROR: test_zeros_big (test_multiarray.TestCreation)
>> ------------------------------------------------------------
>> Traceback (most recent call last):
>>    File "X:\Python27\lib\site-packages\numpy\core\tests\test_multiarray.py",
>> line 594, in test_zeros_big
>>      d = np.zeros((30 * 1024**2,), dtype=dt)
>> MemoryError
>>
>> I would be much obliged if someone else could demonstrate it.
>
> Memory fragmentation in the 2GB address space available? If dt==float64,
> that requires 250MB contiguous.
>

Before creating the dtype('D') test array, the largest contiguous block 
available to the 32 bit Python process on my system is ~830 MB. The 
creation of this array succeeds. However, the creation of the next 
dtype('G') test array fails because the previous array is still in 
memory and the largest contiguous block available is only ~318 MB. 
Deleting the test arrays after usage via del(d) fixes this problem 
<https://github.com/numpy/numpy/pull/7323>. Another fix could be to 
change the order of data types tested.

Christoph