Barak Orly Bejerano

US Patent:

8301851, Oct 30, 2012

Filed:

Jun 16, 2005

Appl. No.:

11/154964

Inventors:

Rong Yu - Franklin MA, US
Peng Yin - South Grafton MA, US
Stephen R. Ives - West Boylston MA, US
Adi Ofer - Framingham MA, US
Gilad Sade - Newton MA, US
Barak Bejerano - Natick MA, US

Assignee:

EMC Corporation - Hopkinton MA

International Classification:

G06F 12/00
G06F 13/00

US Classification:

711158, 711100, 711154, 711200

Abstract:

Scheduling jobs for a plurality of devices includes assigning a run count value to each of the devices, scheduling a number of consecutive jobs up to the run count value, and decrementing the run count value according to the number of consecutive jobs scheduled. The run count value for a particular one of the devices may vary according to a total load of the particular one of the devices. The total load of the particular device may vary according to a number of pending jobs for the particular device and a total number of jobs for all devices coupled to a controller for the devices. The devices may be disk drive devices. Only one read job may be scheduled for a device irrespective of the run count value for the device and devices having pending read jobs may be given precedence over other devices. Multiple read jobs may be scheduled for a device according to the run count value and devices having pending read jobs may be given precedence over other devices. The disk drive devices may be subdivided into a plurality of logical devices.

US Patent:

8423728, Apr 16, 2013

Filed:

Jun 16, 2005

Appl. No.:

11/154234

Inventors:

Rong Yu - Franklin MA, US
Peng Yin - South Grafton MA, US
Stephen R. Ives - West Boylston MA, US
Adi Ofer - Framingham MA, US
Gilad Sade - Newton MA, US
Barak Bejerano - Natick MA, US

Assignee:

EMC Corporation - Hopkinton MA

International Classification:

G06F 12/00
G06F 13/00

US Classification:

711158, 711100, 711154

Abstract:

Scheduling jobs for a plurality of logical devices associated with physical devices includes assigning a physical run count value and a physical skip count value to each of the physical devices, at each iteration, examining the physical skip count value and the physical run count value for each of the physical devices, and scheduling a number of jobs up to the physical run count value for logical devices associated with a particular one of the physical devices at each iteration corresponding to the physical skip count value for the particular one of the physical devices. The physical skip count value and the physical run count value for a particular one of the physical devices may vary according to a total load of the particular physical device. The total load of the particular physical device may vary according to a number of jobs for all logical devices associated with the particular physical device and a total number of all jobs for all physical devices associated with a particular physical device controller.

US Patent:

20170199695, Jul 13, 2017

Filed:

Mar 24, 2017

Appl. No.:

15/468516

Inventors:

- Hopkington MA, US
Kevin Granlund - Sutton MA, US
Seema Pai - Shrewsbury MA, US
Evgeny Malkevich - Newton MA, US
Stephen Richard Ives - West Boylston MA, US
Roii Raz - Providence RI, US
Barak Bejerano - Natick MA, US

International Classification:

G06F 3/06

Abstract:

A distributed network of storage elements (DNSE) is provided in which the physical capacity of each drive is split into a set of equal sized logical splits which are individually protected within the DNSE using separate RAID groups. To reduce restoration latency, members of the RAID groups having a member in common on a given drive are spread within the DNSE to minimize the number of sets of drives within the DNSE that have RAID members in common. By causing the splits to be protected by RAID groups, restoration of the splits may occur in parallel involving multiple drives within the DNSE. By minimizing the overlap between RAID members on various drives, failure of a given drive will not require multiple reads from another drive in the DNSE. Likewise, spare splits are distributed to enable write recovery to be performed in parallel on multiple drives within the DNSE.