# US 2018/0324503 A1 · Data storage system with adaptive data path routing > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2018/0324503 A1 - Document ID: US20180324503A1 - Status: Published application - Kind: A1 - Application number: 15/584,845 - Filed: 2017-05-02 - Published: 2018-11-08 - Earliest claimed: 2017-05-02 - Assignees: Seagate Technology LLC - Applicants: Seagate Technology, LLC - Inventors: Kuntal Rawal - Web page: https://patentgrep.com/patent/US20180324503A1 ## CPC - H04Q 3/0029: {Provisions for intelligent networking} - H04B 1/006: {using switches for selecting the desired band (H04B1/0057 takes precedence)} - H04B 1/44: Transmit/receive switching - H04L 41/147: for predicting network behaviour - H04L 43/0894: Packet rate - H04L 45/24: Multipath - H04Q 11/00: Selecting arrangements for multiplex systems (multiplex systems H04J) - H04W 40/28: for reactive routing - H04L 43/16: Threshold monitoring - H04L 45/028: Dynamic adaptation of the update intervals, e.g. event-triggered updates - H04Q: SELECTING (switches, relays, selectors H01H; wireless communication networks H04W) - H04B: TRANSMISSION - H04L: TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION (arrangements common to telegraphic and telephonic communication H04M) - H04W: WIRELESS COMMUNICATION NETWORKS (broadcast communication H04H; communication systems using wireless links for non-selective communication, e.g. wireless extensions H04M1/72) ## Abstract A data storage system can have adaptive data path routing that consists of a network controller connected to a plurality of data storage units that each have a local controller and memory. A front-end module of the network controller may direct a first data set from a first data storage unit of the plurality of data storage units via a primary data. A back-end routing module of the network controller can adapt to an amount of data accesses by transferring a second data set from a second data storage unit of the plurality of data storage units via a back-end data path. ## Claims ### Claim 1 A system comprising a network controller connected to a plurality of data storage units each comprising a local controller and memory, a first data set directed from a first data storage unit of the plurality of data storage units via a primary data path as directed by a front-end routing module of the network controller, the network controller configured to adapt to an amount of data accesses by transferring a second data set from a second data storage unit of the plurality of data storage units via a back-end data path as directed by a back-end routing module of the network controller. ### Claim 2 (depends on 1) The system of claim 1, wherein the first and second data sets are respectively transferred along the primary and back-end data paths concurrently. ### Claim 3 (depends on 1) The system of claim 1, wherein the second data set is not transferred until the network controller predicts a decrease in system bandwidth. ### Claim 4 (depends on 1) The system of claim 1, wherein the second data set is not transferred until the network controller detects a decrease in system bandwidth. ### Claim 5 (depends on 1) The system of claim 1, wherein the back-end data path has a greater latency than the primary data path. ### Claim 6 (depends on 1) The system of claim 1, wherein the network controller throttles the size of the second data set to provide a threshold system bandwidth. ### Claim 7 (depends on 1) The system of claim 1, wherein the second data set consists of data requests pending in a buffer of the network controller. ### Claim 8 (depends on 7) The system of claim 7, wherein the network controller alters the size of the buffer as a result of the number of pending data requests. ### Claim 9 (depends on 1) The system of claim 1, wherein the first data set is transferred via a single channel of the primary data path. ### Claim 10 A method comprising: connecting a network controller to a plurality of data storage units each comprising a local controller and memory; directing a first data set from a first data storage unit of the plurality of data storage units via a primary data path as directed by a front-end routing module of the network controller; detecting a number of active data storage units in the plurality of data storage units with the network controller; and transferring a second data set from a second data storage unit of the plurality of data storage units via a back-end data path as directed by a back-end routing module of the network controller. ### Claim 11 (depends on 10) The method of claim 10, wherein the network controller ignores a total size of pending data accesses and a total number of pending data accesses. ### Claim 12 (depends on 10) The method of claim 10, wherein the front-end routing module sends all data accesses to the plurality of data storage units via the primary data path while the detected number of active data storage units is below a predetermined first threshold. ### Claim 13 (depends on 12) The method of claim 12, wherein the back-end routing module is inactive until the detected number of active data storage units is above the predetermined first threshold. ### Claim 14 (depends on 12) The method of claim 12, wherein the back-end routing module selects data accesses from a buffer of the network controller to maintain a system data rate provided to at least one host. ### Claim 15 (depends on 12) The method of claim 12, wherein the back-end routing module utilizes a number of different back-end data paths based on a routing schedule maintained by the network controller. ### Claim 16 (depends on 15) The method of claim 15, wherein the routing schedule is altered by the network controller in response to logged system bandwidth. ### Claim 17 (depends on 10) The method of claim 10, wherein the network controller adjusts the routing schedule to accommodate for hysteresis. ### Claim 18 An apparatus comprising a network controller connected to a plurality of data storage units each comprising a local controller and memory, the network controller comprising a front-end routing module and a back-end routing module respectively directing data to the plurality of data storage units via a primary data path and a separate back-end data path in response to a detected number of active data storage units in the plurality of data storage units. ### Claim 19 (depends on 18) The apparatus of claim 18, wherein the primary data path has a greater bandwidth than the back-end data path. ### Claim 20 (depends on 18) The apparatus of claim 18, wherein the primary data path is physically separated from the back-end data path, the primary data path passing through a multi-channel selector upstream of the plurality of data storage units, the back-end data path passing between data storage units of the plurality of data storage units.