[LU-141] port lustre client page cache shrinker back to clio

• Type: Improvement
• Resolution: Fixed
• Priority: Minor
• Fix Version/s: Lustre 2.4.0
• Assignee: WC Triage
• Reporter: Jinshan Xiong (Inactive)

Description

This feature is lost when clio was implemented. We may need to port it back from 1.8.

There will be a lot of changes for this since we need to deal with it under cl_page infrastructure, also it might be better to implement this in obdclass/ instead of llite as what 1.8 does.

this is what we should do:
1. Implement generic cl_page LRU mechanism in obdclass/. This LRU list should not use spinlocks for smp scalability and be able to deal with async_page_max cap.
2. add a shrinker for cl_page in llite - not sure if we still need this.

Issue Links

• is related to: LU-744 Single client's performance degradation on 2.1