Method for performing atomic, concurrent read and write operations on multiple storage devices

Claim 1

A storage system for storing data records, said storage system comprising: a storage medium for storing data records, said data records being indexed by addresses which specify the location of said data records in said storage medium; a controller for receiving, write messages from processors coupled to said controller, each write message including a data segment to be written to said storage medium at a specified address, and coordination information specifying a timestamp, and the addresses of other data records on other storage systems that were written in the same write operation, said timestamp specifying the time at which said processors sent said write messages to said controller a log for storing said write messages; wherein said controller further comprises a clock and wherein said controller periodically reads said timestamps of said write messages in said log and compares said timestamps to said clock to determine said message having the oldest timestamp and wherein said controller writes said data segment contained in said message having the oldest timestamp to said storage medium at said specified address if said timestamp is less than said clock by more than a predetermined amount.

Claim 6

A method for causing a storage system to store and retrieve data across multiple storage devices each of said storage devices comprising: a storage medium for storing data records, said data records being indexed by addresses which specify the location of said data records in said storage medium; a controller for receiving write messages from processors coupled to said controller, each write message including a data segment to be written to said storage medium at a specified address, and coordination information specifying a timestamp, and the addresses of other data records on other storage systems that were written in the same write operation, said timestamp specifying the time at which said processors sent said write messages to said controller; and a log for storing said write messages. said method comprising the steps of: causing a processor wishing to store a data set comprising a plurality of records to be stored on one or more of said storage devices in said storage system to send a write message to each storage device that is to store a portion of said data set each write message comprising said portion of said data set that is to be stored on that storage device, and coordination information specifying a timestamp, and the addresses of said portions of said data set that were included in said write messages sent to other storage devices in said storage system; causing said controller in each of said storage devices to store each write message received by that storage device to be stored in said log included in said storage device; and causing each controller in said storage system to periodically read said timestamps of said write messages in said log included in that storage device, to compare said timestamps to determine said message having the oldest timestamp, and to write said portion of said data set contained in that write message to said storage medium at said specified address if said timestamp indicates that said message has been stored in said log for more than a predetermined amount of time.

Claim 7

A method for causing a storage system to store and retrieve data across multiple storage devices each of said storage devices comprising: a storage medium for storing data records, said data records being indexed by addresses which specify the location of said data records in said storage medium; a controller for receiving write messages from processors coupled to said controller, each write message including a data segment to be written to said storage medium at a specified address, and coordination information specifying a timestamp, and the addresses of other data records on other storage systems that were written in the same write operation, said timestamp specifying the time at which said processors sent said write messages to said controller; and a log for storing said write messages. said method comprising the steps of: causing a processor wishing to store a data set comprising a plurality of records to be stored on one or more of said storage devices in said storage system to send a write message to each storage device that is to store a portion of said data set each write message comprising said portion of said data set that is to be stored on that storage device, and coordination information specifying a timestamp, and the addresses of said portions of said data set that were included in said write messages sent to other storage devices in said storage system; causing said controller in each of said storage devices to store each write message received by that storage device to be stored in said log included in said storage device; and causing each controller in said storage system to periodically read said timestamps of said write messages in said log included in that storage device, to compare said timestamps to determine said message having the oldest timestamp, and to write said portion of said data set contained in that write message to said storage medium at said specified address if said timestamp indicates that said message has been stored in said log for more than a predetermined amount of time.

Claim 8

A method for causing a storage system to store and retrieve data across multiple storage devices each of said storage devices, comprising: a storage medium for storing data records, said data records being indexed by addresses which specify the location of said data records in said storage medium; a controller for receiving write messages from processors coupled to said controller, each write message including a data segment to be written to said storage medium at a specified address, and coordination information specifying a timestamp, and the addresses of other data records on other storage systems that were written in the same write operation, said timestamp specifying the time at which said processors sent said write messages to said controller; and a log for storing said write messages, said method comprising the steps of: causing a processor wishing to store a data set comprising a plurality of records to be stored on one or more of said storage devices in said storage system to send a write message to each storage device that is to store a portion of said data set each write message comprising said portion of said data set that is to be stored on that storage device, and coordination information specifying a timestamp, and the addresses of said portions of said data set that were included in said write messages sent to other storage devices in said storage system; and causing said controller in each of said storage devices to store each write message received by that storage device to be stored in said log included in said storage device, wherein a processor wishing to retrieve a data set from said storage system sends a read message to each storage device in said storage system having a portion of said data set stored therein, each read message comprising information specifying a range of addresses in said storage medium and wherein each controller receiving one of said read messages generates one or more response messages to that read message, each response message comprising an address range in said storage medium that was written in response to a single one of said write messages, the data records stored in said storage medium corresponding to said address range, and the coordination information received in that write message if said coordination information is still stored in that storage device.

Claim 9

A method for causing a storage system to store and retrieve data across multiple storage devices each of said storage devices, comprising: a storage medium for storing data records, said data records being indexed by addresses which specify the location of said data records in said storage medium; a controller for receiving write messages from processors coupled to said controller, each write message including a data segment to be written to said storage medium at a specified address, and coordination information specifying a timestamp, and the addresses of other data records on other storage systems that were written in the same write operation, said timestamp specifying the time at which said processors sent said write messages to said controller; and a log for storing said write messages, said method comprising the steps of: causing a processor wishing to store a data set comprising a plurality of records to be stored on one or more of said storage devices in said storage system to send a write message to each storage device that is to store a portion of said data set each write message comprising said portion of said data set that is to be stored on that storage device, and coordination information specifying a timestamp, and the addresses of said portions of said data set that were included in said write messages sent to other storage devices in said storage system; and causing said controller in each of said storage devices to store each write message received by that storage device to be stored in said log included in said storage device, wherein a processor wishing to retrieve a data set from said storage system sends a read message to each storage device in said storage system having a portion of said data set stored therein, each read message comprising information specifying a range of addresses in said storage medium and wherein each controller receiving one of said read messages generates one or more response messages to that read message, each response message comprising an address range in said storage medium that was written in response to a single one of said write messages, the data records stored in said storage medium corresponding to said address range, and the coordination information received in that write message if said coordination information is still stored in that storage device.