# US 11,442,646 B2 · Identified zones for optimal parity sharing zones > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,442,646 B2 - Document ID: US11442646B2 - Status: Granted - Kind: B2 - Application number: 17/186,764 - Filed: 2021-02-26 - Published: 2022-03-10 - Granted: 2022-09-13 - Earliest claimed: 2020-09-09 - Assignees: Western Digital Technologies, Inc. - Applicants: Western Digital Technologies, Inc. - Inventors: Dinesh Kumar Agarwal - Web page: https://patentgrep.com/patent/US11442646B2 ## CPC - G06F 3/0644: {Management of space entities, e.g. partitions, extents, pools} - G06F 3/0671: {In-line storage system} - G06F 3/0604: {Improving or facilitating administration, e.g. storage management} - G06F 3/0659: {Command handling arrangements, e.g. command buffers, queues, command scheduling} - G06F 3/0673: {Single storage device} - G06F 11/1004: {to protect a block of data words, e.g. CRC or checksum (G06F11/1076 takes precedence; security arrangements for protecting computers or computer systems against unauthorized activity G06F21/00)} - G06F 11/1068: {in sector programmable memories, e.g. flash disk (G06F11/1072 takes precedence)} - G06F 11/108: {Parity data distribution in semiconductor storages, e.g. in SSD} - G06F: ELECTRIC DIGITAL DATA PROCESSING (computer systems based on specific computational models G06N) ## Abstract Storage devices are capable of identifying zones for sharing parity blocks across zones. Active zones may be segregated across multiple active zones having similar zone properties, and grouped so that parity buffers can be shared. By identifying zones for optimal parity sharing, storage devices and systems can: (i) maintain independent parity for all zones during initial zone writes (i.e. during an erased state when data is written directly to pages and not to the zones), (ii) track zone write pointers and frequency of writes in the zones, (iii) segregate zones with higher correlation and group them together, (iv) utilize these groupings placed across various channels so that zones with high correlations, comprising of the zones that are written together and at the same rate, share the parity buffers, and (v) load and XOR individual parity buffers for optimal parity sharing across all zones. ## Claims ### Claim 1 A storage device, comprising: one or more memories; and one or more controllers configured to: maintain independent parity blocks for first zones at an initial zone write command; track a plurality of write command properties associated with the first zones; segregate a plurality of second zones from the first zones, wherein the plurality of second zones are initially associated with first channels; group the plurality of second zones into zone groups; and reallocate the plurality of second zones from the zone groups across a plurality of channels, such that the independent parity blocks are shared with the plurality of second zones of the zone groups based on zones with high correlation. ### Claim 2 (depends on 1) The storage device of claim 1, further comprising loading the independent parity blocks with an XOR circuit for sharing across the zone groups. ### Claim 3 (depends on 1) The storage device of claim 1, wherein the plurality of channels comprises the first channels and second channels. ### Claim 4 (depends on 1) The storage device of claim 1, wherein one or more of the first channels associated with the plurality of second zones are not the same as the second channels of the plurality of second zones. ### Claim 5 (depends on 1) The storage device of claim 1, wherein the plurality of write command properties are comprised of at least one or more of zone write pointers, frequency of writes, and zones written together most of the time. ### Claim 6 (depends on 1) The storage device of claim 1, wherein segregating the plurality of second zones from the first zones is based on the zones with high correlations. ### Claim 7 (depends on 6) The storage device of claim 6, wherein the zones with high correlations are comprised of zones that are written together and at the same rate, and wherein the independent parity blocks are shared with the plurality of second zones of the zone groups based on the zones with high correlation instead of zones with high physical proximity. ### Claim 8 (depends on 1) The storage device of claim 1, wherein the zones with high correlation from the zone groups share a same independent parity blocks. ### Claim 9 A method of identifying zones for parity sharing in a storage device, comprising: maintaining independent parity blocks for first zones at an initial zone write command; tracking a plurality of write command properties associated with the first zones; segregating a plurality of second zones from the first zones, wherein the plurality of second zones are initially associated with first channels; grouping the plurality of second zones into zone groups; reallocating the plurality of second zones from the zone groups across a plurality of channels, wherein the independent parity blocks are shared by the plurality of second zones of the zone groups; and loading the independent parity blocks through an XOR circuit to form loaded parity blocks for sharing across the zone groups. ### Claim 10 (depends on 9) The method of claim 9, wherein the grouping of the plurality of second zones is based on any one of zone writes commands, zones written in conjunction with other zones, and zones which are opened with similar properties, and wherein the similar properties include zones having a same first word line. ### Claim 11 (depends on 9) The method of claim 9, wherein the plurality of channels comprises the first channels and second channels. ### Claim 12 (depends on 9) The method of claim 9, wherein one or more of the first channels associated with the second zones are not the same as the second channels of the second zones. ### Claim 13 (depends on 9) The method of claim 9, wherein the plurality of write command properties are comprised of at least one or more of zone write pointers, frequency of writes, and zones written with equal time stamps. ### Claim 14 (depends on 9) The method of claim 9, wherein segregating the plurality of second zones from the first zones is based on zones with high correlations. ### Claim 15 (depends on 13) The method of claim 13, wherein the zones with high correlations are comprised of zones that are written together and zones that are written at the same rate. ### Claim 16 (depends on 9) The method of claim 9, wherein the zones with higher correlation from the zone groups share the same independent parity blocks. ### Claim 17 A storage device, comprising: one or more memories; and one or more controllers configured to cause: maintaining independent parity blocks for first zones at an initial zone write command; tracking a plurality of write command properties associated with the first zones; segregating a plurality of second zones from the first zones, wherein each of the plurality of second zones are initially associated with first channels; grouping the plurality of second zones into zone groups; reallocating the plurality of second zones from the zone groups across a plurality of channels, wherein the independent parity blocks are shared by the second zones of the zone groups; and loading the independent parity blocks through an XOR circuit so as to form loaded parity blocks for sharing across the zone groups. ### Claim 18 (depends on 17) The storage device of claim 17, wherein the grouping of the plurality of second zones is based on any one of zone writes commands, zones written in conjunction with other zones, and zones which are opened with similar properties, wherein the similar properties include zones having the same first word line. ### Claim 19 (depends on 17) The storage device of claim 17, wherein the plurality of channels comprise the first channels and second channels. ### Claim 20 (depends on 17) The storage device of claim 17, wherein one or more of the first channels associated with the plurality of second zones are not the same as the second channels of the plurality of second zones.