BLOCK I/O INTERFACE FOR A HOST BUS ADAPTER THAT UTILIZES NVDRAM

摘要

A block I/O interface for a HBA is disclosed that dynamically loads regions of a SSD of the HBA to a DRAM of the HBA. One embodiment is an apparatus that includes a host system and a HBA. The HBA includes a SSD and DRAM. The host identifies a block I/O read request for the SSD, identifies a region of the SSD that corresponds to the read request, and determines if the region is cached in the DRAM. If the region is cached in the DRAM, then the HBA copies data for the read request to the host memory and a response to the read request utilizes the host memory. If the region is not cached, then the HBA caches the region of the SSD in the DRAM, copies the data for the read request to the host memory, and a response to the read request utilizes the host memory.

主权项

1. An apparatus comprising:
a host system including a host processor and a host memory; and a Host Bus Adapter (HBA) including a Solid State Disk (SSD) and a Dynamic Random Access Memory (DRAM) that is operable to cache regions of the SSD; the host processor operable to identify a block Input/Output (I/O) read request for the SSD, to identify a region of the SSD that corresponds to the block I/O read request, and to determine if the region of the SSD is cached in the DRAM of the HBA; the host processor, responsive to determining that the region of the SSD is cached in the DRAM of the HBA, is further operable to:
direct the HBA to perform a memory copy of a block of data for the block I/O read request from the cached region of the SSD to the host memory; andrespond to the block I/O read request for the SSD utilizing the block of data in the host memory; the host processor, responsive to determining that the region of the SSD is not cached by the DRAM of the HBA, is further operable to:
direct the HBA to cache the region of the SSD in the DRAM of the HBA;direct the HBA to perform a memory copy of the block of data for the block I/O read request from the cached region of the SSD to the host memory; andrespond to the block I/O read request for the SSD utilizing the block of data in the host memory.