Method of improving performance of a data storage device

摘要

Methods are provided for efficiently storing data to a data storage device or subsystem. The data storage device may be a Solid-State Device (SSD), and may be implemented as part of a RAID (Redundant Array of Independent Disks) or other subsystem. When existing data is read and updated, and must be re-stored, the data is assembled and stored as if it were new data, and is written in a sequential manner, instead of being written to the same storage location. A newer generation number distinguishes it from the previous version. If the storage subsystem employs data striping, stripe size may be matched with the size of a logical collection of data (e.g., an extent), so that each such logical collection of data is wholly stored on just device in the storage subsystem. Concurrent device access may be supported by concurrently writing substripes of data to each device/extent.

主权项

1. A method of storing data, the method comprising:
executing a data reduction application to reduce data exchanged between a client and a server engaged in a client-server communication application; receiving updated data for the data reduction application at a data storage system having a minimum physical write size equal to multiple logical pages of data and characterized by a threshold number of updates to stored data; reading a logical page of data from a first physical offset within the data storage system, wherein the logical page of data includes data corresponding to the updated data; constructing in memory a first new logical page of data to include:
the updated data;new data not already stored in the data storage system; andless than all content of the logical page of data; assigning a new version identifier to the first new logical page; buffering the first new logical page until a threshold number of new logical pages of data, including the first new logical page, are accumulated; and once the threshold number of new logical pages of data have been accumulated,
sequentially writing the first new logical page to a current physical offset within the data storage system instead of to the first physical offset,calculating extent metadata for the threshold number of new logical pages, andwriting the extent metadata to the end or to the beginning of the threshold number of new logical pages.