[Twisted-Python] Python3 twistd daemon for Ubuntu 14.04 alternatives

Glyph Lefkowitz glyph at twistedmatrix.com
Sat Feb 25 16:50:58 MST 2017


> On Feb 25, 2017, at 9:03 AM, Clayton Daley <clayton.daley at gmail.com> wrote:
> 
> Are you talking about building Docker containers on the fly?

Pretty sure Hynek has proper build-server/production separation.

> We use Docker extensively, but our build machine makes images that we push to Dockerhub (private repos).  This has a lot of advantages:
> Our images (on the hub) are effectively pinned at the version they were built
> Our test and production servers (can, if we want) always get exactly the same image (even if we need to rebuild a server months later)
> We test all our servers so we only have to manually pin packages (python or apt) if we run into regressions or other incompatibilities (i.e. an upgraded package that is no longer compatible with a manually pinned package)
> Our build machine caches all the intermediate images (i.e. after each docker step).  We intentionally sequence our images to place oft-changing items at the end.  
> Unless I change the list of apt packages, that layer is never rebuilt.
> We have an extra step that uploads *just* the requirements files before pip installing
> Our last step is the app code so changes to this layer are just a cached layer + PUT (i.e. seconds)
> This optimization also makes our containers super efficient to upgrade because we only download the changed layers
> This sounds like it covers a lot of the PEX advantages plus the added benefits of containerization.

Pex and containerization are completely orthogonal. You can use pex inside or outside of a container, and you can use a container with or without pex.

Hynek lays out a good case against pex inside containers, but the blog post from Moshe that I linked to earlier lays out a good reason to use them together.

-glyph

-------------- next part --------------
An HTML attachment was scrubbed...
URL: </pipermail/twisted-python/attachments/20170225/d072dd3d/attachment-0002.html>


More information about the Twisted-Python mailing list