Emc Corporation

Emc Coropration

Avinoam Zakai

Ruben Michel

David W DesRoches

Victoria Dubrovsky

Shai Bar-Nefy

Tao Kai Lam

Yuval Ofek

Eitan Bachmat

Moshe Schreiber

Load balancing of activities on physical disk storage devices is accomplished by monitoring reading and writing operations to blocks of contiguous storage locations on the physical disk storage devices. A list of exchangeable pairs of blocks is developed based on size and function. Statistics accumulated over an interval are then used to obtain access activity values for each block and each physical disk drive. A statistical analysis leads to a selection of one block pair. After testing to determine any adverse effect of making that change, the exchange is made to more evenly distribute the loading on individual physical disk storage devices.

Load balancing on disk array storage device

A method balances workloads of storage devices of a storage subsystem. The method includes reading a mailbox to obtain control parameters and collecting historical data on numbers of accesses to storage volumes of the storage devices. The control parameters are written in the mailbox by host devices. The method also includes selecting data swaps that lead to better balanced workloads for storage devices based on the historical data. The act of selecting and/or the act of collecting being initialized by the control parameters.

Mailbox for controlling storage subsystem reconfigurations

A method and an apparatus for reconfiguring a storage subsystem by performing an ordered sequence of reconfigurations of physical storage volumes of the storage subsystem. The method and apparatus perform a portion of the sequence of reconfigurations, in response to receiving a rollback request, in an order that is reversed with respect to the order of the sequence.

Rolling back storage subsystem reconfigurations

Growing community of inventors

Cambridge, MA, United States of America

Avinoam Zakai