Variable cache line size management

A method for variable cache line size management, comprising:

• partitioning a cache line of an upper level cache into a plurality of sub-sectors wherein each sub-sector of the cache line has a size corresponding to a size of an unsectored cache line of a lower level cache;
• storing a reference count corresponding to each sub-sector of the upper level cache line;
• responsive to determining that an eviction of the cache line of the upper level cache is to be performed, identifying select sub-sectors to store in the lower level cache based on the reference count associated with each sub-sector of the upper level cache line;
• and
• storing the selected sub-sectors in the lower level cache.

A method for data processing in a data processing system, comprising:

• determining whether an eviction of a cache line from an upper level cache to a lower level cache is to be performed, wherein the upper level cache comprises a plurality of cache lines each being sectored into a plurality of sub-sectors, and wherein the lower level cache comprises a plurality of cache lines each being unsectored, each sub-sector having a size equal to or less than a size of the cache line of the lower level cache;
• responsive to determining that an eviction is to be performed, identifying sub-sectors of the cache line to be evicted;
• determining a reference count for the identified sub-sectors, the reference count indicating a quantity of references to the respective sub-sector;
• comparing the reference counts to a threshold value;
• invalidating the sub-sectors having a reference count being below the threshold value;
• and
• storing the sub-sectors having a reference count meeting or exceeding the threshold value in the lower level cache.