[LU-18942] rework a object limits for zfs from LU-5164

• Type: Improvement
• Resolution: Unresolved
• Priority: Critical
• Severity: 3
• Assignee: Alexey Lyashkov
• Reporter: Alexey Lyashkov

Description

LU-5164 had introduce a limit for lu_object cache to have ability lustre coexist with zfs ARC cache. But this limit had two problems.
1) this is limit for the lu_object caches, but it had no limit for other lustre hashes, like locks.
It produce an extra problems with LRU resize enabled.
2) 79b4ae9139c (Alex Zhuravlev 2012-05-29 14:45:32 +0400 110) lu_site_purge(&env, site, (bytes >> 10)); to optimistic in current days.
in case ARC cache want to flush 1G ram it request to flush a whole lu_size cache.