Re: [Numpy-discussion] Python global interpreter lock ...

[Konrad H. <hi...@cn...>]

On Wednesday 30 April 2003 08:47, Andrew P. Lentvorski, Jr. wrote:

> 1) Does numpy (or numarray) release the Python GIL?

No.

> 2) If not, why not?  Is this simply something I could fix by making the
> changes myself, or are there larger reasons for not releasing the GIL?

There is one good reason, which is that the GIL release code doesn't nest=
=2E If=20
NumPy released the GIL during its operations, then any C code that uses N=
umPy=20
functions would have to reacquire the GIL before calling NumPy, then=20
re-release the GIL afterwards. In most real-life situations, it is simple=
r=20
and presumably more efficient to release the GIL once for a block of=20
numerical computations, which would include many calls to NumPy functions=
=2E

One could of course release the GIL not within the functions that are par=
t of=20
the NumPy C API, but in a thin wrapper around it that is directly called =
from=20
Python.

The only other problem that I see is the general object type arrays, whic=
h=20
make calls back into the Python interpreter.

Konrad.
--=20
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