[HDFS-14053] Provide ability for NN to re-replicate based on topology changes.

• Type: Improvement
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Fix Version/s: 3.3.0

Environment

VMWare w/ local storage

• Hadoop Flags: Reviewed
• Release Note: A new option (-replicate) is added to fsck command to re-trigger the replication for mis-replicated blocks. This option should be used instead of previous workaround of increasing and then decreasing replication factor (using hadoop fs -setrep command).
• Assignee: Hrishikesh Gadre
• Reporter: ellen johansen
• Created: 11/Dec/14 16:02
• Updated: 25/Jul/19 14:50
• Resolved: 06/Nov/18 05:41

Description

Enabling HVE/node awareness does not rebalance replicas on data that existed prior to topology changes.

[root@vmw-d10-001 jenkins]# more /opt/cloudera/topology.data
10.20.xxx.161 /rack1/nodegroup1
10.20.xxx.162 /rack1/nodegroup1
10.20.xxx.163 /rack3/nodegroup1
10.20.xxx.164 /rack3/nodegroup1
172.17.xxx.71 /rack2/nodegroup1
172.17.xxx.72 /rack2/nodegroup1

before HVE:
/user/impalauser/tpcds/store_sales <dir>
/user/impalauser/tpcds/store_sales/store_sales.dat 1180463121 bytes, 9 block(s): OK
0. BP-1184748135-172.17.xxx.71-1418235396548:blk_1073742xxx_1382 len=134217728 repl=3 [10.20.xxx.164:20002, 10.20.xxx.161:20002, 10.20.xxx.163:20002]
1. BP-1184748135-172.17.xxx.71-1418235396548:blk_1073742213_1389 len=134217728 repl=3 [10.20.xxx.164:20002, 172.17.xxx.72:20002, 10.20.xxx.161:20002]
2. BP-1184748135-172.17.xxx.71-1418235396548:blk_1073742214_1390 len=134217728 repl=3 [10.20.xxx.164:20002, 172.17.xxx.72:20002, 10.20.xxx.163:20002]
3. BP-1184748135-172.17.xxx.71-1418235396548:blk_1073742215_1391 len=134217728 repl=3 [10.20.xxx.164:20002, 172.17.xxx.72:20002, 10.20.xxx.163:20002]
4. BP-1184748135-172.17.xxx.71-1418235396548:blk_1073742216_1392 len=134217728 repl=3 [10.20.xxx.164:20002, 10.20.xxx.161:20002, 172.17.xxx.72:20002]
5. BP-1184748135-172.17.xxx.71-1418235396548:blk_1073742217_1393 len=134217728 repl=3 [10.20.xxx.164:20002, 172.17.xxx.72:20002, 10.20.xxx.163:20002]
6. BP-1184748135-172.17.xxx.71-1418235396548:blk_1073742220_1396 len=134217728 repl=3 [10.20.xxx.164:20002, 10.20.xxx.162:20002, 10.20.xxx.163:20002]
7. BP-1184748135-172.17.xxx.71-1418235396548:blk_1073742222_1398 len=134217728 repl=3 [10.20.xxx.164:20002, 10.20.xxx.163:20002, 10.20.xxx.161:20002]
8. BP-1184748135-172.17.xxx.71-1418235396548:blk_1073742224_1400 len=106721297 repl=3 [10.20.xxx.164:20002, 10.20.xxx.162:20002, 172.17.xxx.72:20002]
---------

Before enabling HVE:
Status: HEALTHY
Total size: 1648156454 B (Total open files size: 498 B)
Total dirs: 138
Total files: 384
Total symlinks: 0 (Files currently being written: 6)
Total blocks (validated): 390 (avg. block size 4226042 B) (Total open file blocks (not validated): 6)
Minimally replicated blocks: 390 (100.0 %)
Over-replicated blocks: 0 (0.0 %)
Under-replicated blocks: 1 (0.25641027 %)
Mis-replicated blocks: 0 (0.0 %)
Default replication factor: 3
Average block replication: 2.8564103
Corrupt blocks: 0
Missing replicas: 5 (0.44682753 %)
Number of data-nodes: 5
Number of racks: 1
FSCK ended at Wed Dec 10 14:04:35 EST 2014 in 50 milliseconds

The filesystem under path '/' is HEALTHY

------
after HVE (and NN restart):

/user/impalauser/tpcds/store_sales <dir>
/user/impalauser/tpcds/store_sales/store_sales.dat 1180463121 bytes, 9 block(s): OK
0. BP-1184748135-172.17.xxx.71-1418235396548:blk_1073742xxx_1382 len=134217728 repl=3 [10.20.xxx.164:20002, 10.20.xxx.163:20002, 10.20.xxx.161:20002]
1. BP-1184748135-172.17.xxx.71-1418235396548:blk_1073742213_1389 len=134217728 repl=3 [172.17.xxx.72:20002, 10.20.xxx.164:20002, 10.20.xxx.161:20002]
2. BP-1184748135-172.17.xxx.71-1418235396548:blk_1073742214_1390 len=134217728 repl=3 [172.17.xxx.72:20002, 10.20.xxx.164:20002, 10.20.xxx.163:20002]
3. BP-1184748135-172.17.xxx.71-1418235396548:blk_1073742215_1391 len=134217728 repl=3 [172.17.xxx.72:20002, 10.20.xxx.164:20002, 10.20.xxx.163:20002]
4. BP-1184748135-172.17.xxx.71-1418235396548:blk_1073742216_1392 len=134217728 repl=3 [172.17.xxx.72:20002, 10.20.xxx.164:20002, 10.20.xxx.161:20002]
5. BP-1184748135-172.17.xxx.71-1418235396548:blk_1073742217_1393 len=134217728 repl=3 [172.17.xxx.72:20002, 10.20.xxx.164:20002, 10.20.xxx.163:20002]
6. BP-1184748135-172.17.xxx.71-1418235396548:blk_1073742220_1396 len=134217728 repl=3 [10.20.xxx.164:20002, 10.20.xxx.163:20002, 10.20.xxx.162:20002]
7. BP-1184748135-172.17.xxx.71-1418235396548:blk_1073742222_1398 len=134217728 repl=3 [10.20.xxx.164:20002, 10.20.xxx.163:20002, 10.20.xxx.161:20002]
8. BP-1184748135-172.17.xxx.71-1418235396548:blk_1073742224_1400 len=106721297 repl=3 [172.17.xxx.72:20002, 10.20.xxx.164:20002, 10.20.xxx.162:20002]

Status: HEALTHY
Total size: 1659427036 B (Total open files size: 498 B)
Total dirs: 176
Total files: 529
Total symlinks: 0 (Files currently being written: 6)
Total blocks (validated): 532 (avg. block size 3119223 B) (Total open file blocks (not validated): 6)
Minimally replicated blocks: 532 (100.0 %)
Over-replicated blocks: 0 (0.0 %)
Under-replicated blocks: 1 (0.18796992 %)
Mis-replicated blocks: 0 (0.0 %)
Default replication factor: 3
Average block replication: 2.8383458
Corrupt blocks: 0
Missing replicas: 7 (0.46143705 %)
Number of data-nodes: 5
Number of racks: 3
FSCK ended at Wed Dec 10 14:29:23 EST 2014 in 115 milliseconds
The filesystem under path '/' is HEALTHY

------------

store sales pushed to hdfs after HVE was configured:

/user/impalauser/tpcds_after_hve <dir>
/user/impalauser/tpcds_after_hve/store_sales.dat 1180463121 bytes, 9 block(s): OK
0. BP-1184748135-172.17.xxx.71-1418235396548:blk_1073743406_2582 len=134217728 repl=3 [10.20.xxx.164:20002, 10.20.xxx.161:20002, 172.17.xxx.72:20002]
1. BP-1184748135-172.17.xxx.71-1418235396548:blk_1073743412_2588 len=134217728 repl=3 [10.20.xxx.164:20002, 10.20.xxx.162:20002, 172.17.xxx.72:20002]
2. BP-1184748135-172.17.xxx.71-1418235396548:blk_1073743415_2591 len=134217728 repl=3 [10.20.xxx.164:20002, 10.20.xxx.161:20002, 172.17.xxx.72:20002]
3. BP-1184748135-172.17.xxx.71-1418235396548:blk_1073743416_2592 len=134217728 repl=3 [10.20.xxx.164:20002, 10.20.xxx.162:20002, 172.17.xxx.72:20002]
4. BP-1184748135-172.17.xxx.71-1418235396548:blk_1073743417_2593 len=134217728 repl=3 [10.20.xxx.164:20002, 10.20.xxx.161:20002, 172.17.xxx.72:20002]
5. BP-1184748135-172.17.xxx.71-1418235396548:blk_1073743418_2594 len=134217728 repl=3 [10.20.xxx.164:20002, 10.20.xxx.161:20002, 172.17.xxx.72:20002]
6. BP-1184748135-172.17.xxx.71-1418235396548:blk_1073743419_2595 len=134217728 repl=3 [10.20.xxx.164:20002, 10.20.xxx.161:20002, 172.17.xxx.72:20002]
7. BP-1184748135-172.17.xxx.71-1418235396548:blk_1073743422_2598 len=134217728 repl=3 [172.17.xxx.72:20002, 10.20.xxx.164:20002, 10.20.xxx.162:20002]
8. BP-1184748135-172.17.xxx.71-1418235396548:blk_1073743423_2599 len=106721297 repl=3 [10.20.xxx.164:20002, 10.20.xxx.161:20002, 172.17.xxx.72:20002]

Issue Links

• relates to: HDFS-14642 processMisReplicatedBlocks does not return correct processed count