Handle environments where locks are not available

[mckinsel]

Blosc want to acquire a lock, but locks aren't available in all environments. In particular, AWS Lambda lacks /dev/shm, so trying to use blosc will raise an OSError:

>>> import numcodecs.blosc
OSError: [Errno 38] Function not implemented

This changes handles missing locks more gracefully by just turning of threads.

[alimanfoo]

Thanks Marcus, just back from holidays, will take a look asap.

…

On Thursday, 23 August 2018, Marcus Kinsella ***@***.***> wrote: Blosc want to acquire a lock, but locks aren't available in all environments. In particular, AWS Lambda lacks /dev/shm, so trying to use blosc will raise an OSError: >>> import numcodecs.bloscOSError: [Errno 38] Function not implemented This changes handles missing locks more gracefully by just turning of threads. ------------------------------ You can view, comment on, or merge this pull request online at: #83 Commit Summary - Handle environments where locks are not available File Changes - *M* numcodecs/blosc.pyx <https://github.com/zarr-developers/numcodecs/pull/83/files#diff-0> (10) Patch Links: - https://github.com/zarr-developers/numcodecs/pull/83.patch - https://github.com/zarr-developers/numcodecs/pull/83.diff — You are receiving this because you are subscribed to this thread. Reply to this email directly, view it on GitHub <#83>, or mute the thread <https://github.com/notifications/unsubscribe-auth/AAq8QkJ2aLElSIeWCSuTbhmh8PBUQvndks5uTvlMgaJpZM4WKFnl> .

-- If I do not respond to an email within a few days, please feel free to resend your email and/or contact me by other means. Alistair Miles Head of Epidemiological Informatics Centre for Genomics and Global Health Big Data Institute Li Ka Shing Centre for Health Information and Discovery Old Road Campus Headington Oxford OX3 7LF United Kingdom Phone: +44 (0)1865 743596 or +44 (0)7866 541624 Email: alimanfoo@googlemail.com Web: http://a <http://purl.org/net/aliman>limanfoo.github.io/ Twitter: @alimanfoo <https://twitter.com/alimanfoo>

[tomwhite]

I hit the same problem on AWS Lambda, and needed to handle another case in numcodecs __init__.py file where the number of cores is queried and multiprocessing throws another OSError. I used this fix (in addition to Marcus' one in this PR): tomwhite@c54bc3d

[alimanfoo]

Thanks @tomwhite for the feedback. This should be prioritised for the next release.

[tomwhite]

@alimanfoo that would be great. Thanks.

[alimanfoo]

Looks good, sorry for delay in reviewing.

[alimanfoo]

Thanks @mckinsel.

[tomwhite]

@alimanfoo thanks for merging this. Would you be able to take a look at the related change in #93 too please, as I needed that change to successfully run on AWS Lambda.