I/O operations for data reduction shared volumes (DRS-VOLs) requires access to cached metadata. Metadata cache uses the same CLPR as the cache of user data.
To achieve a metadata cache hit to get optimal performance, in addition to the cache capacity recommended when Dynamic Provisioning applies (see Cache capacity with Dynamic Provisioning or Dynamic Provisioning for Mainframe ), it is recommended to increase the CLPR capacity by 0.15% of the total capacity of DRS-VOLs belonging to the CLPR. If the CLPR capacity cannot be increased due to the limits on the maximum cache capacity, it is recommended to install the maximum CLPR capacity.
recommended-cache-capacity-with-capacity-saving-enabled = total-used-capacity-of-DRS-VOLs × 0.15%
The <total-used-capacity-of-DRS-VOLs> differs from the total defined capacity of the volumes. <total-used-capacity-of-DRS-VOLs> is the capacity expected to be used at initial implementation. In addition to the capacity used at initial implementation, we recommend that you include in <total-used-capacity-of-DRS-VOLs> additional capacity to be used in the future. Note that the capacity used in a TIA S-VOL is the capacity of differential data with the TIA P-VOL.
If the resulting value is smaller than 32 GB, set the result to 32 GB.