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Ghost does not support clustering or multiple dynos (CDN/HTTP-cache required to scale)

See original GitHub issue

Hey @cobyism 👋 I’ve had a look at this Ghost/Heroku setup and unfortunately it promotes some practices that will result in broken Ghost installations.

Ghost does not support clustering in any form due to in-memory caches that will result in each instance getting out of sync with each other - there can only be 1 instance of Ghost for each site.

Can you please remove any mention of clustering, scaling up of dynos (unless advising not to do so!), and the use of node-cluster?

Issue Analytics

  • State:closed
  • Created 5 years ago
  • Comments:16

github_iconTop GitHub Comments

marscommented, Feb 7, 2019

Thanks for your reponse @johnonolan

I’m very happy to hear that Ghost can squeeze so much performance out of a single thread of javascript. That is clearly a testament to Ghost’s engineering practices and history to have so much confidence about this architecture.

Heroku’s dyno scaling is not just for “scaling code” but also to support rolling deployments without downtime and to load balance across healthy dynos if a server/dyno suffers hardware failure.

I always prefer operating a service that can scale horizontally, separate from whether or not the “code scales properly”.

How do you deploy new versions of a Ghost server without downtime or deal with hardware outages if Ghost does not support multiple servers?

JohnONolancommented, May 21, 2022

To clarify, @mars, this issue was opened by way of an olive branch as an offer of help and guidance. We had both discussed and intended to offer to take over the project and have it officially maintained by the Ghore core team.

Unfortunately the petty hostility in this thread put an end to that idea.

All the best

Read more comments on GitHub >

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