[SERVER-5514] Data not balanced accross all the shards Created: 05/Apr/12 Updated: 15/Aug/12 Resolved: 09/Apr/12 |
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| Status: | Closed |
| Project: | Core Server |
| Component/s: | Stability |
| Affects Version/s: | 2.0.1 |
| Fix Version/s: | None |
| Type: | Bug | Priority: | Major - P3 |
| Reporter: | Preetham Derangula | Assignee: | Unassigned |
| Resolution: | Done | Votes: | 0 |
| Labels: | None | ||
| Remaining Estimate: | Not Specified | ||
| Time Spent: | Not Specified | ||
| Original Estimate: | Not Specified | ||
| Environment: |
Linux |
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| Operating System: | Linux | ||||||||||||
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| Description |
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I have 7 shards and 1 Router and 1 Config server. All the shards and servers are running on VMs.One of the shards is allocated excessive data. This is the same machine that was acting up and exhausted all the diskspace in the previous issue that I have raised before. We deleted all the data and config and started on clean slate. I have raised a related issue which details the history of this issue
Observation look at the mapped and vsize 5.95 and 12.5
Observation: look at the mapped and vsize 1.95 and 4.42 *****************************
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| Comments |
| Comment by Preetham Derangula [ 09/Apr/12 ] |
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Thanks a lot! |
| Comment by Scott Hernandez (Inactive) [ 09/Apr/12 ] |
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Also, |
| Comment by Preetham Derangula [ 09/Apr/12 ] |
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Thanks. |
| Comment by Scott Hernandez (Inactive) [ 09/Apr/12 ] |
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Yes: |
| Comment by Preetham Derangula [ 09/Apr/12 ] |
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One other question, I can write a maintenance job to repair database and clearing moveChunks periodically? But, do you guys have any plans of solving this internally within Mongo subsytems in further releases? Just curious and greedy |
| Comment by Scott Hernandez (Inactive) [ 09/Apr/12 ] |
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Yes, you can remove those files periodically. Probably worth keeping a few days (or longer). |
| Comment by Preetham Derangula [ 09/Apr/12 ] |
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Thanks. Repairing individual shard was a good idea and it has shrunk storaze size. |
| Comment by Scott Hernandez (Inactive) [ 07/Apr/12 ] |
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Just on the one shard to start with. The total for the database files allocated (on all shards) are around 33GB, but only 11GB of data (storage) is used. Because this is spread around many shards and each might have 2-4 GB of extra space (pre-allocated files) you can see how these numbers aren't going to accurately reflect the real data size when added up for the sharded cluster. |
| Comment by Preetham Derangula [ 06/Apr/12 ] |
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Reapair on just shard LRCHB00363 or the whole shard network?If you look at LRCHB00363 it has more than 11GB insert query update delete getmore command flushes mapped vsize res faults |
| Comment by Scott Hernandez (Inactive) [ 06/Apr/12 ] |
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It looks like the number of chunks are even across the shards but shard3 (LRCHB00363) has more files allocated and more data stored. Can you do a repair database to see if you have fragmentation there? Also, with so little data (less than 11GB for the sharded DB) you will not so even file storage across the shards because of pre-allocation: http://www.mongodb.org/display/DOCS/Excessive+Disk+Space |
| Comment by Preetham Derangula [ 05/Apr/12 ] |
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Attached |
| Comment by Scott Hernandez (Inactive) [ 05/Apr/12 ] |
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Please attach the results of db.printShardingStatus(), the logs from mongos, and a mongodump of the config database. |