sql dba CheckPoint VSLazy Writer
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CheckPoint |
Lazy Writer |
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1. Flush dirty pages to Disk |
1. Flush dirty pages to disk. |
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2. Flush only Data pages to disk |
2. Check for available memory and removed Buffer pool (execution plan/compile plan/ Data pages /Memory objects) |
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3. Default, Occurs approximately every 1 minute |
3. Occurs depending upon memory pressure and resource availability |
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4. Can be managed with sp_confige -recovery interval option |
4. It is lazy, Sql server manages by its own. |
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5. Does not check the memory pressure |
5. Monitor the memory pressure and try maintain the available free memory. |
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6. crash recovery process will be fast to read log as data file is updated. |
6. No role in recovery |
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7. Occurs for any DDL statement |
7. Occurs per requirement |
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8. Occurs before Backup/Detach command |
8. Occurs per requirement |
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9. Depends upon the configuration setting, we can control. |
9. Works on Least recent used pages and removed unused plans first, no user control. |
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10. for simple recovery it flush the tlog file after 70% full. |
10. No effect on recovery model. |
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11. can manually /Forcefully run command “Checkpoint” |
11.No command for Lazy Writer |
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12. Very Less performance impact |
12. No performance impact |