[LU-13970] add an option to disable inode cache on Lustre client

• Type: Improvement
• Resolution: Fixed
• Priority: Minor
• Fix Version/s: Lustre 2.16.0
• Assignee: Lai Siyao
• Reporter: Lai Siyao

Description

By default inode is cached on Lustre client, to avoid OOM, an option like llite.*.inode_cache can be added, when it's turned off, inode is immediately released on last iput().

Issue Links

• is related to: LU-14408 very large lustre_inode_cache
• is related to: LU-11092 NMI watchdog: BUG: soft lockup - CPU#12 stuck for 23s! [ptlrpcd_00_18:4222]
• is related to: LU-13983 rmdir should release inode on Lustre client
• is related to: LU-13833 hook llite to inode cache shrinker
• is related to: LU-13909 release invalid dentries proactively on client