A host access instruction is received from one of a plurality of channels which are served in parallel. The host access instruction includes an address range of one or more addresses and a type of access. The address range and type of access are compared against a table of stored address ranges and stored types of access associated with any pending host access instructions. It is determined whether to execute the host access instruction based at least in part on the comparison. If it is decided to execute the host access instruction, the host access instruction is forwarded for execution and the address range and the type of access from the host access instruction are stored in the table.