Emc Corporation

Arkologic Limited

Rajesh Ananthanarayanan

Ronald Lee

Poulo Kuriakose

Henry C Lau

Robert Tower Frey

Chao Zhang

Kyquang Son

Hawkins Yao

Harinder Pal Singh Bhasin

Ambrish Verma

A solid state device (SSD) write operation management system including a file system that incorporates SSD status information into its operational logic is disclosed. By incorporating SSD status information, the system achieves various advantages over conventional systems, such as enhanced write performance and extended SSD lifespan. The system processes various criteria to select the optimal virtual device ('vdev') for data allocation in response to a write request. The first criterion utilizes Program/Erase counts of physical blocks contained in the SSDs. Another criterion is the number of physical free blocks of a drive. If the average of the selected vdev's physical free blocks is higher than the OP threshold, then the system selects for data allocation the vdev with the greatest amount of logical free space. In the instance that the average is lower, the system schedules garbage collection for the vdev.

Solid state device write operation management system

A file system-aware SSD management system including an SSD management module that incorporates both file system information and information related to the underlying physical solid-state storage media into its operations is described. Also described are related methods for performing data management operations in a file system-aware manner. By incorporating both file system and physical storage information, the system may achieve various advantages over conventional systems, such as enhanced I/O performance, simplified SSD firmware, and extended SSD lifespan. Moreover, by moving solid-state management functions above the firmware level, the system may enable the simultaneous management of a pool of multiple SSDs.

File system-aware solid-state storage management system

Systems and methods in accordance with various disclosed embodiments can manage a mirrored virtual target to synchronize the members of the virtual target and/or to verify that the members of the virtual target are synchronized. In one embodiment, a mirrored virtual target is synchronized by first provisioning at least one first internal virtual logical unit (IVLU) corresponding to at least one destination target of the mirrored target and a second IVLU corresponding to a source target of the mirrored target. A write command is first issued, via one or more internal virtual logical units, to each of the destination target members of the mirrored target. When each destination target is available to receive data, as evidenced by a returned transfer ready signal, a read command is provided to the source target via the second internal virtual logical unit. In this manner, a data path between the source and destination targets is established prior to reading data from the source target. Accordingly, the data can be read from the source target, converted to write data, and routed to the destination targets at line speed without buffering of the data. A similar process is provided to verify that the members of a mirrored target are synchronized. In one embodiment, a system and method is provided to manage incoming commands for the mirrored target while synchronizing or verifying synchronization of the mirrored target. Incoming commands can be queued as they are received and provided to the mirrored target when pending synchronization or verification commands are completed.

Online initial mirror synchronization and mirror synchronization verification in storage area networks

Systems and methods in accordance with embodiments are provided for the replication of data from virtual logical units to remote virtual logical units. Change logs can be provided at a primary storage switch including a primary VLU to indicate changes made to the primary VLU between replications. The change log can also be used to resynchronize a member split from the primary VLU during a replication operation. Members can be split from the primary VLU and used in a split virtual logical unit at the primary VLU for replication. The remaining member(s) of the primary VLU can be used to maintain the primary VLU online for host devices during the replication operation. A remote VLU at a remote storage switch can be exported as a physical logical unit to the primary storage switch where it is provisioned for a member of a replication VLU at the primary storage switch.

Storage switch asynchronous replication

Growing community of inventors

San Jose, CA, United States of America

Rajesh Ananthanarayanan