The past few weeks have been very busy in our offices as we announced the creation of Microsoft Open Technologies, Inc. Now that the dust has settled it’s time for us to resume our regular cadence in releasing code, and we are happy to share with you the very first deliverable from our new company: a new and significant iteration of our work on Redis on Windows, the open-source, networked, in-memory, key-value data store.

The major improvements in this latest version involve the process of saving data on disk. Redis on Linux uses an OS feature called Fork/Copy On Write. This feature is not available on Windows, so we had to find a way to be able to mimic the same behavior without changing completely the save on disk process so as to avoid any future integration issues with the Redis code.

The version we released today implements the Copy On Write process at the application level: instead of relying on the OS we added code to Redis so that some data structures are duplicated in such a way that Redis can still serve requests from clients while saving data on disk (thus achieving the same effect of Fork/Copy On Write does automatically on Linux).

You can find the code for this new version on the new MS Open Tech repository in GitHub, which is currently the place to work on the Windows version of Redis as per guidance from Salvatore Sanfilippo, the original author of the project. We will also continue working with the community to create a solid Windows port.

We consider this not to be production ready code, but a solid code base to be shared with the community to solicit feedback: as such, while we pursue stabilization, we are keeping the older version as default/stable on the GitHub repository. To try out the new code, please go to the bksavecow branch.

In the next few weeks we plan to extensively test the code so that developers can use it for more serious testing. In the meantime, we will keep looking at the ‘save on disk’ process to find out if there are other opportunities to make the code perform even better. We will promote the bksavecow branch to master as soon as we (and you!) are confident the code is stable.

Please send your feedback, file suggestions and issues to our GitHub repository. We look forward to further iterations and to working with the Redis community at large to make the Windows experience even better.

Claudio Caldato

Principal Program Manager

Microsoft Open Technologies, Inc.

A subsidiary of Microsoft Corporation.