Utilizing a persistent write cache as a redo log

A storage control system receives a first write request and a second write request following the first write request. The first and second write requests comprise respective first and second data items for storage to a primary storage. First and second cache write operations are performed in parallel to write the first and second data items a persistent write cache. The first cache write operation comprises a split write operation which comprises writing a parsing header for the first data item to the write cache, and writing a payload of the first data item to the write cache. The second cache write operation comprises storing the second data item and associated metadata in the write cache, and waiting for an acknowledgment that the parsing header for the first data item has been successfully stored in the write cache before returning an acknowledgment indicating successful storage of the second data item.