Change the SSD cache flush ratio

This article describes the following topics

• Changing the SSD cache ratio to meet your need

Connect to a Controller

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Profile - default

• will begin flushing dirty objects when 20% of the pool is dirty and begin evicting clean objects when we reach 60% of the target size.

ceph osd pool set cachepool cache_target_full_ratio 0.6ceph osd pool set cachepool cache_target_dirty_high_ratio 0.4ceph osd pool set cachepool cache_target_dirty_ratio 0.2

Profile - slow

• will begin flushing dirty objects when 40% of the pool is dirty and begin evicting clean objects when we reach 80% of the target size.

ceph osd pool set cachepool cache_target_full_ratio 0.8ceph osd pool set cachepool cache_target_dirty_high_ratio 0.6ceph osd pool set cachepool cache_target_dirty_ratio 0.4

Profile - fast

• will begin flushing dirty objects when 10% of the pool is dirty and begin evicting clean objects when we reach 30% of the target size.

ceph osd pool set cachepool cache_target_full_ratio 0.3ceph osd pool set cachepool cache_target_dirty_high_ratio 0.2ceph osd pool set cachepool cache_target_dirty_ratio 0.1