Movatterモバイル変換

innodb_compression_level lets you turn the degree of compression up or down. A higher value lets you fit more data onto a storage device, at the expense of more CPU overhead during compression. A lower value lets you reduce CPU overhead when storage space is not critical, or you expect the data is not especially compressible.

innodb_compression_failure_threshold_pct specifies a cutoff point forcompression failures during updates to a compressed table. When this threshold is passed, MySQL begins to leave additional free space within each new compressed page, dynamically adjusting the amount of free space up to the percentage of page size specified byinnodb_compression_pad_pct_max

innodb_compression_pad_pct_max lets you adjust the maximum amount of space reserved within eachpage to record changes to compressed rows, without needing to compress the entire page again. The higher the value, the more changes can be recorded without recompressing the page. MySQL uses a variable amount of free space for the pages within each compressed table, only when a designated percentage of compression operations“fail” at runtime, requiring an expensive operation to split the compressed page.

innodb_log_compressed_pages lets you disable writing of images ofre-compressedpages to theredo log. Re-compression may occur when changes are made to compressed data. This option is enabled by default to prevent corruption that could occur if a different version of thezlib compression algorithm is used during recovery. If you are certain that thezlib version is not subject to change, disableinnodb_log_compressed_pages to reduce redo log generation for workloads that modify compressed data.