When trying to build edit 60000 posts I'm getting an out of memory error
How big are the documents, and what are the specs of your server? We likely load them all into memory. You should be able to do some calculations on whether your server can handle such an operation.
It's likely a resource issue on the server, is there any way to do it without loading xxx thousand documents into memory?
Not how it is currently implemented. You'd likely need to batch them programmatically in manageable batch sizes.
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