# US 2014/0156936 A1 · Systems and methods for managing destage conflicts > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2014/0156936 A1 - Document ID: US20140156936A1 - Status: Published application - Kind: A1 - Application number: 14/174,683 - Filed: 2014-02-06 - Published: 2014-06-05 - Earliest claimed: 2010-12-10 - Assignees: International Business Machines Corporation - Applicants: International Business Machines Corporation - Inventors: Brent C. BEARDSLEY; Michael T. BENHASE; Binny S. GILL; Lokesh M. GUPTA; Sonny E. WILLIAMS - Web page: https://patentgrep.com/patent/US20140156936A1 ## CPC - G06F 12/0891: using clearing, invalidating or resetting means - G06F 12/023: {Free address space management} - G06F 12/0804: with main memory updating (G06F12/0806 takes precedence) - G06F 12/0866: for peripheral storage systems, e.g. disk cache - G06F: ELECTRIC DIGITAL DATA PROCESSING (computer systems based on specific computational models G06N) ## Abstract Destaging storage tracks from each rank that includes a greater than a predetermined percentage of a predetermined amount of storage space with respect to a current amount of storage space allocated to each rank until the current amount of storage space used by each respective rank is equal to the predetermined percentage of the predetermined amount of storage space. The destage storage tracks are declined from being destaged from each rank that includes less than or equal to the predetermined percentage of the predetermined amount of storage space rank. ## Claims ### Claim 1 A method for managing destage conflicts in a cache partitioned into a plurality of ranks configured to store a plurality of storage tracks using a processor device, the method comprising: destaging storage tracks from each rank that includes greater than a predetermined percentage of a predetermined amount of storage space with respect to a current amount of storage space allocated to each rank until the current amount of storage space used by each respective rank is equal to the predetermined percentage of the predetermined amount of storage space; and declining to destage storage tracks from each rank that includes less than or equal to the predetermined percentage of the predetermined amount of storage space. ### Claim 2 (depends on 1) The method of claim 1, further including performing at least one of: allocating an amount of storage space in the cache to each rank, monitoring the current amount of storage space used by each rank with respect to the amount of storage space allocated to each respective rank, and ceasing to destage storage tracks from each rank that includes the predetermined percentage of the predetermined amount of storage space. ### Claim 3 (depends on 1) The method of claim 1, wherein allocating the amount of storage space in the cache comprises allocating no more that twenty five percent (25%) of a total amount of storage space in the cache to any one rank. ### Claim 4 (depends on 3) The method of claim 3, wherein ceasing to destage storage tracks from each rank comprises ceasing to destage storage tracks from each rank that includes less than or equal to thirty percent (30%) of its respective allocated storage space. ### Claim 5 (depends on 3) The method of claim 3, wherein ceasing to destage storage tracks from each rank comprises ceasing to destage storage tracks from each rank that includes less than or equal to a predetermined number of storage tracks. ### Claim 6 (depends on 2) The method of claim 2, wherein destaging storage tracks from each rank comprises: determining a current amount of storage tracks in the cache, utilizing a formula to determine a current number of destage tasks to utilize to destage storage tracks from the cache, the current number of destage storage tasks based on the current amount of storage tracks in the cache, and utilizing the current number of destage storage tasks to destage the plurality of storage tracks. ### Claim 7 (depends on 6) The method of claim 6, wherein ceasing to destage storage tracks comprises reducing the current number of destage tasks to zero on each rank that includes less than or equal to the predetermined percentage of the predetermined amount of storage space. ### Claim 8 A system for managing destage conflicts in cache, comprising: a cache partitioned into a plurality of ranks configured to store a plurality of storage tracks; and a processor coupled to the cache, wherein the processor: destages storage tracks from each rank that includes greater than a predetermined percentage of a predetermined amount of storage space with respect to a current amount of storage space allocated to each rank until the current amount of storage space used by each respective rank is equal to the predetermined percentage of the predetermined amount of storage space, and declines to destage storage tracks from each rank that includes less than or equal to the predetermined percentage of the predetermined amount of storage space. ### Claim 9 (depends on 8) The system of claim 8, wherein the processor performs at least one of: allocating an amount of storage space in the cache to each rank, monitoring the current amount of storage space used by each rank with respect to the amount of storage space allocated to each respective rank, and ceasing to destage storage tracks from each rank that includes the predetermined percentage of the predetermined amount of storage space. ### Claim 10 (depends on 8) The system of claim 8, wherein the processor allocates no more that twenty five percent (25%) of a total amount of storage space in the cache to any one rank. ### Claim 11 (depends on 10) The system of claim 10, wherein the processor ceases destaging storage tracks from each rank that includes less than or equal to thirty percent (30%) of its respective allocated storage space. ### Claim 12 (depends on 10) The system of claim 10, wherein the processor ceases destaging storage tracks from each rank that includes less than or equal to a predetermined number of storage tracks. ### Claim 13 (depends on 9) The system of claim 9, wherein, when destaging storage tracks from each rank, the processor: determines a current amount of storage tracks in the cache, utilizes a formula to determine a current number of destage tasks to utilize to destage storage tracks from the cache, the current number of destage storage tasks based on the current amount of storage tracks in the cache, and utilizes the current number of destage storage tasks to destage the plurality of storage tracks. ### Claim 14 (depends on 13) The system of claim 13, wherein, when ceasing to destage storage tracks, the processor reduces the current number of destage tasks to zero on each rank that includes less than or equal to the predetermined percentage of the predetermined amount of storage space. ### Claim 15 A physical computer storage memory comprising a computer program product method for managing destage conflicts in a cache partitioned into a plurality of ranks configured to store a plurality of storage tracks, the physical computer storage medium comprising: computer code that destages storage tracks from each rank that includes greater than a predetermined percentage of a predetermined amount of storage space with respect to a current amount of storage space allocated to each rank until the current amount of storage space used by each respective rank is equal to the predetermined percentage of the predetermined amount of storage space; and computer code that declines to destage storage tracks from each rank that includes less than or equal to the predetermined percentage of the predetermined amount of storage space. ### Claim 16 (depends on 15) The physical computer storage memory of claim 15, further comprising computer code that: allocates an amount of storage space in the cache to each rank, monitors the current amount of storage space used by each rank with respect to the amount of storage space allocated to each respective rank, and ceases to destage storage tracks from each rank that includes the predetermined percentage of the predetermined amount of storage space. ### Claim 17 (depends on 15) The physical computer storage memory of claim 15, further comprising computer code that ceases to destage storage tracks from each rank that includes less than or equal to thirty percent (30%) of its respective allocated storage space. ### Claim 18 (depends on 16) The physical computer storage memory of claim 16, further comprising computer code that ceases to destage storage tracks from each rank that includes less than or equal to a predetermined number of storage tracks. ### Claim 19 (depends on 16) The physical computer storage memory of claim 16, further comprising computer code that: determines a current amount of storage tracks in the cache, utilizes a formula to determine a current number of destage tasks to utilize to destage storage tracks from the cache, the current number of destage storage tasks based on the current amount of storage tracks in the cache, and utilizes the current number of destage storage tasks to destage the plurality of storage tracks. ### Claim 20 (depends on 19) The physical computer storage memory of claim 19, further comprising computer code that reduces the current number of destage tasks to zero on each rank that includes less than or equal to the predetermined percentage of the predetermined amount of storage space.