[Numpy-discussion] Default builds of OpenBLAS development branch are now fork safe

[Matthew Brett]

Hi,

On Wed, Mar 26, 2014 at 11:34 AM, Julian Taylor
<jtaylor.debian at googlemail.com> wrote:
> On 26.03.2014 16:27, Olivier Grisel wrote:
>> Hi Carl,
>>
>> I installed Python 2.7.6 64 bits on a windows server instance from
>> rackspace cloud and then ran get-pip.py and then could successfully
>> install the numpy and scipy wheel packages from your google drive
>> folder. I tested dot products and scipy.linalg.svd and they work as
>> expected.
>>
>
>>
>> Would it make sense to embed the blas and lapack header files as part
>> of this numpy wheel and make numpy.distutils.system_info return the
>> lib and include folder pointing to the embedded libopenblas.dll and
>> header files so has to make third party libraries directly buildable
>> against those?
>>
>
> as for using openblas by default in binary builds, no.
> pthread openblas build is now fork safe which is great but it is still
> not reliable enough for a default.
> E.g. the current latest release 0.2.8 still has one crash bug on
> dgemv[1], and wrong results zherk/zer2[2] and dgemv/cgemv[3].
> git head has the former four fixed bug still has wrong results for cgemv.

I noticed the Carl was only getting three test failures on scipy - are
these related?

======================================================================
FAIL: test_decomp.test_eigh('general ', 6, 'F', True, False, False, (2, 4))
----------------------------------------------------------------------
Traceback (most recent call last):
  File "D:\devel\py27\lib\site-packages\nose\case.py", line 197, in runTest
    self.test(*self.arg)
  File "D:\devel\py27\lib\site-packages\scipy\linalg\tests\test_decomp.py",
line 642, in eigenhproblem_general
    assert_array_almost_equal(diag2_, ones(diag2_.shape[0]), DIGITS[dtype])
  File "D:\devel\py27\lib\site-packages\numpy\testing\utils.py", line
811, in assert_array_almost_equal
    header=('Arrays are not almost equal to %d decimals' % decimal))
  File "D:\devel\py27\lib\site-packages\numpy\testing\utils.py", line
644, in assert_array_compare
    raise AssertionError(msg)
AssertionError:
Arrays are not almost equal to 4 decimals

(mismatch 100.0%)
 x: array([ 0.,  0.,  0.], dtype=float32)
 y: array([ 1.,  1.,  1.])

======================================================================
FAIL: Tests for the minimize wrapper.
----------------------------------------------------------------------
Traceback (most recent call last):
  File "D:\devel\py27\lib\site-packages\nose\case.py", line 197, in runTest
    self.test(*self.arg)
  File "D:\devel\py27\lib\site-packages\scipy\optimize\tests\test_optimize.py",
line 435, in test_minimize
    self.test_powell(True)
  File "D:\devel\py27\lib\site-packages\scipy\optimize\tests\test_optimize.py",
line 209, in test_powell
    atol=1e-14, rtol=1e-7)
  File "D:\devel\py27\lib\site-packages\numpy\testing\utils.py", line
1181, in assert_allclose
    verbose=verbose, header=header)
  File "D:\devel\py27\lib\site-packages\numpy\testing\utils.py", line
644, in assert_array_compare
    raise AssertionError(msg)
AssertionError:
Not equal to tolerance rtol=1e-07, atol=1e-14

(mismatch 100.0%)
 x: array([[ 0.75077639, -0.44156936,  0.47100962],
       [ 0.75077639, -0.44156936,  0.48052496],
       [ 1.50155279, -0.88313872,  0.95153458],...
 y: array([[ 0.72949016, -0.44156936,  0.47100962],
       [ 0.72949016, -0.44156936,  0.48052496],
       [ 1.45898031, -0.88313872,  0.95153458],...

======================================================================
FAIL: Powell (direction set) optimization routine
----------------------------------------------------------------------
Traceback (most recent call last):
  File "D:\devel\py27\lib\site-packages\nose\case.py", line 197, in runTest
    self.test(*self.arg)
  File "D:\devel\py27\lib\site-packages\scipy\optimize\tests\test_optimize.py",
line 209, in test_powell
    atol=1e-14, rtol=1e-7)
  File "D:\devel\py27\lib\site-packages\numpy\testing\utils.py", line
1181, in assert_allclose
    verbose=verbose, header=header)
  File "D:\devel\py27\lib\site-packages\numpy\testing\utils.py", line
644, in assert_array_compare
    raise AssertionError(msg)
AssertionError:
Not equal to tolerance rtol=1e-07, atol=1e-14

(mismatch 100.0%)
 x: array([[ 0.75077639, -0.44156936,  0.47100962],
       [ 0.75077639, -0.44156936,  0.48052496],
       [ 1.50155279, -0.88313872,  0.95153458],...
 y: array([[ 0.72949016, -0.44156936,  0.47100962],
       [ 0.72949016, -0.44156936,  0.48052496],
       [ 1.45898031, -0.88313872,  0.95153458],...

----------------------------------------------------------------------
Ran 8940 tests in 143.892s

> Openblas is great if you do not have the patience to build ATLAS and
> only use a restricted set of functionality and platforms you can easily
> test.

I don't think it's possible to build ATLAS on Windows 64-bit at the
moment, and it would take a lot of work to make it build, and Clint W
has said he does not want to invest much time maintaining the Windows
build, so unless something changes, I think ATLAS is not a viable
option - for 64 bits at least.

Cheers,

Matthew