Replacement of a block with a compressed block to increase capacity of a memory-side cache

Systems, apparatuses and methods may provide for identifying a first block and a second block, wherein the first block includes a first plurality of cache lines, the second block includes a second plurality of cache lines, and the second block resides in a memory-side cache. Additionally, each cache line in the first plurality of cache lines may be compressed with a corresponding cache line in the second plurality of cache lines to obtain a compressed block that includes a third plurality of cache lines. In one example, the second block is replaced in the memory-side cache with the compressed block if the compressed block satisfies a size condition.