[LU-3124] bad interaction between layout lock and wide striping

• Type: Bug
• Resolution: Fixed
• Priority: Blocker
• Fix Version/s: Lustre 2.4.0
• Affects Version/s: Lustre 2.4.0
• Labels: MB
• Severity: 3
• Assignee: Jinshan Xiong (Inactive)
• Reporter: Johann Lombardi (Inactive)

Description

To implement the layout lock, Fanyong and Jinshan added a LVB to ibit lock so that the LOV EA can be packed in completion ASTs. However, for wide-striped files, the client is not expecting such a big LVB buffer in an AST.
I think the MDT should have a upper LVB limit over which it only packs the "header" (i.e. the most important field is the generation) and the OST FID list will have to be fetched via another RPC from the client.

Issue Links

• is related to: LU-2807 lockup in server completion ast -> lu_object_find_at
• is related to: LU-2807 lockup in server completion ast -> lu_object_find_at