Patent ID: 9344525
Filing Date: 2016-05-17
CPC Classification: G06F,H04L

Claim Text:
1. A system for managing the storage of data, comprising: a first data storage system and a second data storage system; a plurality of storage processors disposed in a fabric between a client processor, and the first data storage system and the second data storage system, the storage processors having coherency links operable during a time period when data is migrated from the first storage system to the second storage system; wherein a group of the plurality of storage processors are configured to migrate data stored in a range of data addresses of the first data storage system to the second data storage system such that the client processor can access data stored in the range of data addresses of the first data system during the time period when data is migrated and the migration is performed iteratively; and, wherein data stored in the first data system and the second data system is accessed by logical unit number (LUN) and logical block address (LBA); a bitmap is evaluated after completion of a migration iteration and chunks that have been migrated are eliminated from the bitmap and the remaining chunks that have not been migrated divided into sub-chunks having a reduced extent; and, when a rate of reduction in a number of unset bits in the has reached a preset lower value, client write commands are inhibited and a remainder of the data of the LUN is migrated to the second data system.