[LU-11347] Do not use pagecache for SSD I/O when read/write cache are disabled

• Type: Improvement
• Resolution: Fixed
• Priority: Major
• Fix Version/s: Lustre 2.12.0
• Labels: perf_optimization
• Assignee: Alex Zhuravlev
• Reporter: Joseph Gmitter (Inactive)

Description

For SSD optimization, disable pagecache for IO when:

• non-rotational storage is used
• when both read and write caches are disabled

Issue Links

• is related to: LU-5375 Failure on test suite sanity test_151 test_156: roc_hit is not safe to use
• is related to: LU-13680 large allocations in osd_bufs_get() failing
• is related to: LU-12179 allocate continuous pages when disabled page caches
• is related to: LU-9252 osd: Cannot really disable cache on OSS
• is related to: LU-11164 lvbo_*() methods to reuse env
• is related to: LU-12071 bypass pagecache for large files