For the general process of submitting patches to Ceph, read the below

Submitting Patches

For documentation patches the following guide will help you get started

Documenting Ceph

Performance enhancements must come with test data and detailed explanations.

Code cleanup is appreciated, as are patches that fix bugs or implement features. Except on rare occasions, code cleanup that only relates to coding style or modifies whitespace is discouraged, primarily because it can cause problems when rebasing and backporting.