Updated at: 2022-12-09 03:49:50
As time goes by, your backup data will take up more and more space due to data redundancy, leading to high cost of data management and less backup storage space. In this case, to reduce space occupation, lower the cost and maximize the use of resources, we recommend you to configure the following options when creating backup jobs.
§    Enable data deduplication
Before enabling data deduplication, you must create deduplication volume, fingerprint pool and fingerprint library first, see Best Practices for Data Deduplication for details. For how to enable data deduplication, see Step 4 Select Backup Media and Configure Backup Options. You can obtain the deduplication ratio of a backup job by checking the job execution information in the History tab, see History for details. Generally, the more the data repetition, the higher the deduplication ratio. The initial deduplication ratio for GaussDB A database can achieve about 90%, while the ratio for GaussDB T database ranges from 1% to 40%, which is relatively low.
F Note:
A. Deduplication ratio: (completed backup data size - actual restored data size) / completed backup data size.
B. The ratio values are only for your reference as the deduplication ratio is closely related to the data size and data content. In extreme cases, the ratio can be close to 100% or 0.
§    Enable data compression
For how to enable data compression, see Step 4 Select Backup Media and Configure Backup Options. After the option is enabled, you can choose quick or deep compression. The performance of a recovery job with deep compression enabled is slightly worse than that with quick compression enabled. For how to choose appropriate compression type, see Data Compression. You can obtain the actual backup data size by checking the execution information in the History tab, see History for details.
As the compression for GaussDB database is source compression, the data transferred is the data after compression. Generally, the compression ratio of deep compression is between 1/6 and 1/13, and that of quick compression is between 1/2 and 1/9.
F Note:
A. When data deduplication and compression are enabled at the same time, higher compression ratio and performance can be achieved. Generally, data can be compressed to 1/10-1/15 if both deduplication and deep compression are enabled; and data can be compressed to 1/5-1/15 if both deduplication and quick compression are enabled.
B. As both deduplication and compression consume more CPU space and memory, ensure sufficient server resources before these two options are enabled.
C. The ratio values are only for your reference as the deduplication ratio is closely related to the data size and data content. In extreme cases, the ratio can be close to 100% or 0.