pytorch-pip-shim 0.1.0

Description:

pytorchpipshim 0.1.0

pytorch-pip-shim


package


code


tests





What is it?
Why do I need it?
How do I install it?
How do I use it?
How do I uninstall it?
How do I configure it?
How does it work?



Disclaimer
Neither this project (pytorch-pip-shim) nor its author
(Philip Meier) are affiliated with
PyTorch in any way. PyTorch and any related
marks are
trademarks of Facebook, Inc.


What is it?
pytorch-pip-shim is a small background utility that eases the installation process
with pip for PyTorch and third-party packages that depend on its distributions.
After the shim is inserted, you can install PyTorch with pip like you do with any
other package.


Why do I need it?
PyTorch is fully pip install able, but PyPI, the default pip search index, has
some limitations:

PyPI regularly only allows binaries up to a size of
approximately 60 MB. You
can request a file size limit increase
(and the PyTorch team probably did that), but it is still not enough: the Windows
binaries cannot be installed through PyPI
due to their size.
PyTorch uses local version specifiers to indicate for which computation backend the
binary was compiled, for example torch==1.6.0+cpu. Unfortunately, local
specifiers are not allowed on PyPI. Thus, only the binaries compiled with the latest
CUDA version are uploaded. If you do not have a CUDA capable GPU, downloading this
is only a waste of bandwidth and disk capacity. If on the other hand simply don’t
have the latest CUDA driver installed, you can’t use any of the GPU features.

To overcome this, PyTorch alos hosts all binaries
themselves. To access them, you
still can use pip install, but have to use some
additional options:
$ pip install torch==1.6.0+cpu -f https://download.pytorch.org/whl/torch_stable.html
While this is certainly an improvement, it also has it downside: in addition to the
computation backend, the version has to be specified exactly. Without knowing what the
latest release is, it is impossible to install it as simple as pip install torch
normally would.
At this point you might justifiably as: why don’t you just use conda as PyTorch
recommends?
$ conda install pytorch cpuonly -c pytorch
This should cover all cases, right? Well, almost. The above command is enough if you
just need PyTorch. Imagine the case of a package that depends on PyTorch, but
cannot be installed with conda since it is hosted on PyPI? You can’t use the -f
option since the package in question is not hosted by PyTorch. Thus, you now have to
manually track down (and resolve in the case of multiple packages) the PyTorch
distributions, install them in a first step and only install the actual package (and
all other dependencies) afterwards.
If just want to use pip install like you always did before without worrying about
any of the stuff above, pytorch-pip-shim was made for you.


How do I install it?
Installing pytorch-pip-shim is as easy as
$ pip install pytorch-pip-shim
Since it depends on pip and it might be upgraded during installation,
Windows users should
install it with
$ python -m pip install pytorch-pip-shim


How do I use it?
After pytorch-pip-shim is installed there is only a single step to insert the shim:
$ pytorch-pip-shim insert
After that you can use pip as you did before and pytorch-pip-shim handles the
computation backend auto-detection for you in the background.
If you want to remove the shim you can do so with
$ pytorch-pip-shim remove
You can check its status with
$ pytorch-pip-shim status


How do I uninstall it?
Uninstalling is as easy as
$ pip uninstall pytorch-pip-shim
By doing so, pytorch-pip-shim automatically removes the shim if inserted.


How do I configure it?
Once inserted, you don’t need to configure anything. If you don’t want the computation
backend auto-detected but rather want to set it manually pytorch-pip-shim adds two
CLI options to pip install:

--computation-backend <computation_backend>
--cpu



How does it work?
The authors of pip do not condone the use of pip internals as they might
break without warning. As a results of this, pip has no capability for plugins to
hook into specific tasks. Thus, the only way to patch pip s functionality is to
adapt its source in-place. Although this is really bad practice, it is unavoidable for
the goal of this package.
pystiche-pip-shim inserts a shim into the pip main file, which decorates the
main function. Everytime you call pip install, some aspects of the installation
process are patched:

While searching for a download link for a PyTorch distribution, pytorch-pip-shim
replaces the default search index. This is equivalent to calling pip install with
the -f option only for PyTorch distributions.
While evaluating possible PyTorch installation candidates, pytorch-pip-shim culls
binaries not compatible with the available hardware.