Seagate Technology Incorporated

Lsi Corporation

Prasad Ramchandra Kadam

Indrajit Zagade

Vishal Thakkar

Mandar Dattatraya Joshi

Saurabh Balkrishna Khanvilkar

Vidyadhar Pinglikar

Shankar More

Sachin Sudhir Jagtap

Jameer Babasaheb Mulani

Kedar Patankar

KaruppuSwamy Thangaraj

A RAID storage management system includes a plurality of RAID storage devices and a controller configured to manage the plurality of RAID storage devices. The RAID storage management system also includes at least one expander operatively connected to the controller and operatively connected to the plurality of RAID storage devices. The expander is configured to receive a request from the controller for a RAID operation. The expander is also configured to, upon receiving the request, operate to assist the controller in performing the requested RAID operation.

Raid performance by offloading tasks to expanders

An apparatus may include a virtual flash device configured to emulate a flash memory device. The virtual flash device may include a flash interface configured to communicate with a flash controller, an address translation module configured to translate memory addresses from a flash based memory space to another memory space of another memory, a metadata and control module configured to manage metadata from the emulation of the flash memory device, and a non-flash memory controller configured to communicate with the other memory.

Virtual flash system

An apparatus having a memory and a controller is disclosed. The memory may have a write head and sectors in tracks. The controller may have a sector map and a translation map and may be configured to (i) receive a write command having a logical block address and a range value, (ii) examine the sector map to find a sector sequence (a) marked free, (b) about to reach the write head and (c) at least as long as the range value, (iii) write new data in the sector sequence, (iv) update the translation map to associate the logical block address of the write command with a physical address of the written sectors and (v) update the sector map according to the sectors written. Each entry in the sector map generally corresponds to a respective sector and indicates whether the respective sector contains valid data or is free.

Sector translation layer for hard disk drives

A method of priority based connection arbitration in a SAS topology is disclosed introducing a PRIORITY field to an SAS open Address Frame (OAF). As the expander arbitrates the multiple OAFs in competition for an Expander Link, it compares the PRIORITY fields of the arbitrating OAFs. The OAF with highest value of PRIORITY is awarded the destination connection path. In case of equal PRIORITY, the next arbitration is based on the value of Arbitration Wait Time (AWT). This priority based arbitration ensures high availability of SAS connection links to the SAS targets with high priority OAFs which in turn will lead to better quality of service for those SAS targets. PRIORITY field in the OAF is set by the SAS targets based on the current OAF priority and also set by directly attached SAS storage expanders through a modification of the OAF during transit through the expander.

Priority based connection arbitration in a SAS topology to facilitate quality of service (QoS) in SAS transport

A storage system comprising: a SCSI initiator being configured for receiving a data request and providing a SMP request corresponding to the data request, the SCSI initiator being further configured for encapsulating the SMP request into a first SCSI command; a SCSI target being configured for receiving the first SCSI command, the SCSI target being further configured for recognizing encapsulation of the SMP request and obtaining the SMP request from the first SCSI command; and an SMP target being configured for processing the SMP request and providing an SMP response to the SCSI target. The SCSI target being further configured for acknowledging the SCSI initiator upon reception of the SMP response; and the SCSI initiator being further configured for sending a second SCSI command to the SCSI target to retrieve the SMP response.

Growing community of inventors

Pune, India

Prasad Ramchandra Kadam