Various embodiments mitigate busy time in a hierarchical store-through memory cache structure including a cache directory associated with a memory cache. The cache directory is divided into a plurality of portions each associated with a portion of memory cache. A determination is made that a first subpipe of a shared cache pipeline comprises a non-store request. The shared pipeline is communicatively coupled to the plurality of portions of the cache directory. A store command is prevented from being placed in a second subpipe of the shared cache pipeline based on determining that a first subpipe of the shared cache pipeline comprises a non-store request. Simultaneous cache lookup operations are supported between the plurality of portions of the cache directory and cache write operations. Two or more store commands simultaneously processed in a shared cache pipeline communicatively coupled to the plurality of portions of the cache directory.