A data storage system configured for efficient mirroring of data between paired redundant controllers is provided. More particularly, in response to the receipt of customer data from a host for storage, a first controller segments the received customer data into one or more frames of data. In addition, the first controller determines or associates certain metadata for each frame of customer data, and inserts that metadata in the corresponding frame. The frames, including the metadata, are provided to a secondary controller. The secondary controller stores the customer data from a received frame in memory, and stores the corresponding metadata in another location of memory that is indexed to the location where the customer data was stored. The secondary controller may also associate a count value with each frame of data in order to distinguish the most recent frame of data should frames in memory have matching metadata.