PR review Request: Reduce backend preparation overhead by serializing model only once

[IceTDrinker]

Hello,

This is an issue I ran into with large models, the serialization is costly and is done twice currently to prepare backends (once by check_model and once more to actually run the model). I have a PR here : #8270

Comments and feedbacks welcome as I don't seem able to ping the code owner of this file.

Cheers,

IceTDrinker

Edit: I don't know how to ping the relevant code owners for review, sorry about that