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- Manage Snapshot Storage >
- Configure Block Size in a Blockstore
Configure Block Size in a Blockstore¶
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Overview¶
When you back up your deployment to a Blockstores, the Backup Daemon first takes a snapshot of the head database. It then breaks this snapshot into blocks and writes these blocks to the blockstore.
The different blockstores have different default sizes and ranges of sizes for blocks.
Blockstore Type | Block Size Range | Default Size |
---|---|---|
MongoDB | 64 KB to 15 MB | 64 KB |
S3 | 64 KB to 16 MB | 16 MB |
You can change the block size to suit your use case.
Considerations¶
In general, increasing block size results in faster snapshots and restores, but requires more disk space. These competing factors should be considered when determining if you wish to tune the block size.
There are two exceptions where performance improves as the block size increases without requiring additional disk space:
Workload | Impact |
---|---|
Update- and Delete-Intensive | No matter how small you make the block size, the entire block file is rewritten. Since the entire file is always rewritten, there is no difference in storage space if you change the block size. |
Insert-only | The existing blocks never change. As you increase block size, block management is simplified. This enables the best possible performance on snapshot and restore. |