[LU-17261] stat(2) should be able to use a good replica

• Type: Improvement
• Resolution: Unresolved
• Priority: Minor
• Fix Version/s: Lustre 2.16.0
• Severity: 3
• Assignee: Alex Zhuravlev
• Reporter: Alex Zhuravlev

Description

a replica representation in LOV EA can be broken like this one:

lcm_layout_gen: 7
lcm_mirror_count: 2
lcm_entry_count: 2
lcme_id: 65538
lcme_mirror_id: 1
lcme_flags: init,stale
lcme_extent.e_start: 134217728
lcme_extent.e_end: 1073741824
lmm_stripe_count: 16
lmm_stripe_size: 16777216
lmm_pattern: 40000001
lmm_layout_gen: 1
lmm_stripe_offset: 4294967295
lmm_objects:
- 0: { l_ost_idx: -1, l_fid: [0:0x0:0x0] }
- 1: { l_ost_idx: -1, l_fid: [0:0x0:0x0] }
- 2: { l_ost_idx: -1, l_fid: [0:0x0:0x0] }
- 3: { l_ost_idx: 5, l_fid: [0xbc0000406:0x42fce0eb:0x0] }
- 4: { l_ost_idx: -1, l_fid: [0:0x0:0x0] }
- 5: { l_ost_idx: -1, l_fid: [0:0x0:0x0] }
- 6: { l_ost_idx: -1, l_fid: [0:0x0:0x0] }
- 7: { l_ost_idx: -1, l_fid: [0:0x0:0x0] }
- 8: { l_ost_idx: -1, l_fid: [0:0x0:0x0] }
- 9: { l_ost_idx: -1, l_fid: [0:0x0:0x0] }
- 10: { l_ost_idx: -1, l_fid: [0:0x0:0x0] }
- 11: { l_ost_idx: -1, l_fid: [0:0x0:0x0] }
- 12: { l_ost_idx: -1, l_fid: [0:0x0:0x0] }
- 13: { l_ost_idx: -1, l_fid: [0:0x0:0x0] }
- 14: { l_ost_idx: -1, l_fid: [0:0x0:0x0] }
- 15: { l_ost_idx: -1, l_fid: [0:0x0:0x0] }
 
lcme_id: 131073
lcme_mirror_id: 2
lcme_flags: init
lcme_extent.e_start: 0
lcme_extent.e_end: EOF
lmm_stripe_count: 16
lmm_stripe_size: 1048576
lmm_pattern: raid0
lmm_layout_gen: 0
lmm_stripe_offset: 5
lmm_pool: hdd-pool
lmm_objects:
- 0: { l_ost_idx: 5, l_fid: [0xbc0000406:0x42feb0aa:0x0] }
- 1: { l_ost_idx: 8, l_fid: [0x8c0000402:0x3bf10cb:0x0] }
- 2: { l_ost_idx: 15, l_fid: [0x9c0000402:0x11f1d8f:0x0] }
- 3: { l_ost_idx: 13, l_fid: [0x900000402:0x77529c35:0x0] }
- 4: { l_ost_idx: 0, l_fid: [0x300000403:0x3beded4:0x0] }
- 5: { l_ost_idx: 7, l_fid: [0xa80000402:0x11e9898:0x0] }
- 6: { l_ost_idx: 12, l_fid: [0x880000402:0x3bef34f:0x0] }
- 7: { l_ost_idx: 10, l_fid: [0xa40000402:0x11d9d9d:0x0] }
- 8: { l_ost_idx: 14, l_fid: [0xa00000402:0x11e4d68:0x0] }
- 9: { l_ost_idx: 2, l_fid: [0xb80000402:0x11d545a:0x0] }
- 10: { l_ost_idx: 6, l_fid: [0xb40000400:0x11f22d9:0x0] }
- 11: { l_ost_idx: 4, l_fid: [0x2c0000403:0x4016eb6:0x0] }
- 12: { l_ost_idx: 9, l_fid: [0x940000402:0xaf7b184a:0x0] }
- 13: { l_ost_idx: 11, l_fid: [0x980000402:0x11dc273:0x0] }
- 14: { l_ost_idx: 1, l_fid: [0xac0000404:0x3015313c:0x0] }
- 15: { l_ost_idx: 3, l_fid: [0xb00000400:0x11dd9bb:0x0] } 

but regular stat should use any valid replica, not return an error once a bogus one is met.

Issue Links

• is related to: LU-17721 sanity-flr/210b fails: something went wrong with unlink