Michael J Scheer

US Patent:

7680875, Mar 16, 2010

Filed:

Apr 1, 2002

Appl. No.:

10/113235

Inventors:

Jonathon E. Shopiro - Scotch Plains NJ, US
Michael D. Scheer - Summit NJ, US

Assignee:

Novell, Inc. - Provo UT

International Classification:

G06F 15/16
G06F 13/00

US Classification:

709200, 711100

Abstract:

Markers are established in a data object to provide a means to refer to specified parts of the object. Each marker is established within the object by giving the location and length of the part of the object that is to be marked. The marker continues to mark that part of the object as changes are made elsewhere in the object. As data is received into the cache computer it is stored in a sequence of buffers. A plurality of filters, all executing concurrently, search for different interesting string in the object. Each filter finds its interesting strings and marks them using the markers. The result of filtering data of the object is a marker attribute table identifying each of the markers by the offset and length of the interesting strings located by the filters. Vend time is the time at which the object is streamed out of the cache to a client computer. Before the data is vended, a User Data Filter (UDF) executes a call function which sets up a string substitution table.

US Patent:

7822927, Oct 26, 2010

Filed:

May 14, 2007

Appl. No.:

11/748457

Inventors:

Michael D. Scheer - Summit NJ, US

Assignee:

EMC Corporation - Hopkinton MA

International Classification:

G06F 17/30
G06F 12/08

US Classification:

711133, 711216, 707829

Abstract:

A directory name lookup cache (DNLC) provides a hashed forward mapping for finding the “child handle” associated with a “parent handle” and a “child name. ” To provide an efficient reverse lookup capability, a second set of links is added to each cache entry for a “child hash list” indexed by a hashing of the child handle. For dynamically enabling and disabling the reverse mapping, when a new cache entry is added to its parent hash list, if the reverse mapping is enabled, then the new cache entry is also added to its child hash list; otherwise, the new cache entry is marked to indicate that it is not in any child hash list. To save memory, the parent hash lists and the child hash lists may share hash buckets.

US Patent:

8407265, Mar 26, 2013

Filed:

Nov 19, 2010

Appl. No.:

12/950996

Inventors:

Michael D. Scheer - Summit NJ, US
Jean-Pierre Bono - Westboro MA, US
Morgan Clark - South Orange NJ, US
Hongliang Tang - Shrewsbury MA, US
Sairam Veeraswamy - South Grafton MA, US
Pranit Sethi - Somerset NJ, US
Alexander S. Mathews - Jamesburg NJ, US

Assignee:

EMC Corporation - Hopkinton MA

International Classification:

G06F 12/00

US Classification:

707823, 711170, 711111, 711112, 711114

Abstract:

In a file server, a file system is built upon a volume of data storage. The file system includes multiple cylinder groups. Each cylinder group includes file system blocks. The file system blocks include allocated blocks and free blocks. The volume includes slices of storage, and each slice stores at least one of the cylinder groups. A hierarchical slice map has a top level that includes a count of free blocks in the file system, an upper level that includes a count of free blocks in groups of the slices, an intermediate level that includes a count of the free blocks in sub-groups of the slices, and a bottom level that includes a count of the free blocks in each slice of storage. To find a free block for allocation to a file, the slice map hierarchy is searched in a top-down fashion.