1. A computer system comprising:
a client computer configured to send read and write requests over a network;
a data storage subsystem coupled to the network configured to receive the read and write requests, the data storage subsystem comprising a plurality of storage devices;
wherein the data storage subsystem further comprises a storage controller configured to:
identify a unit of data stored in the data storage subsystem, wherein said unit of data is stored across at least a first storage device and a second storage device of the plurality of storage devices, each of the first storage device and the second storage device storing intra-device redundancy data corresponding to the unit of data; and
change an amount of intra-device redundancy data corresponding to the unit of data on only the first storage device.
2. The computer system as recited in claim 1, wherein said unit of data is a RAID stripe.
3. The computer system as recited in claim 1, wherein the storage controller is configured to change said amount of intra-device redundancy data stored on the first storage device in response to detecting an indication of a change in reliability of the first storage device.
4. The computer system as recited in claim 3, wherein the storage controller is further configured to store data indicative of characteristics of the plurality of storage devices, and wherein said change in reliability is based at least in part on the characteristics.
5. The computer system as recited in claim 1, wherein the storage controller is configured to change said amount of intra-device redundancy data stored on the first storage device in response to detecting a characteristic of the first storage device, the characteristic being one or more of an error rate, an access rate, an age, an occupancy level, an expected life of data, and an age of stored data.
6. The computer system as recited in claim 1, wherein between two successive writes of two successive stripes among the plurality of storage devices, the storage controller is configured to determine for at least two different storage devices of the plurality of storage devices new distinct values for respective amounts of storage space for user data and corresponding intra-device redundancy data.
7. The computer system as recited in claim 2, wherein each of the plurality of storage devices comprises solid-state memory.
8. The computer system as recited in claim 1, wherein each of the first storage device and the second storage device further include a checksum for stored user data of the unit of data, and wherein in response to a read to at least a portion of the unit of data the storage controller is configured to:
utilize the checksum to validate corresponding read data; and
utilize intra-device redundancy data to rebuild the corresponding read data in response to detecting the checksum indicates the read data is not valid.
9. A method for use in a computing system, the method comprising:
receiving read and write requests at a data storage subsystem, the data storage subsystem comprising a plurality of storage devices;
identifying a unit of data stored in the data storage subsystem, wherein said unit of data is stored across at least a first storage device and a second storage device of the plurality of storage devices, each of the first storage device and the second storage device storing intra-device redundancy data corresponding to the unit of data; and
changing an amount of intra-device redundancy data corresponding to the unit of data on only the first storage device.
10. The method as recited in claim 9, wherein said unit of data is a RAID stripe.
11. The method as recited in claim 9, further comprising changing said amount of intra-device redundancy data stored on the first storage device in response to detecting an indication of a change in reliability of the first storage device.
12. The method as recited in claim 11, further comprising storing data indicative of characteristics of the plurality of storage devices, and wherein said change in reliability is based at least in part on the characteristics.
13. The method as recited in claim 9, further comprising changing said amount of intra-device redundancy data stored on the first storage device in response to detecting a characteristic of the first storage device, the characteristic being one or more of an error rate, an access rate, an age, an occupancy level, an expected life of data, and an age of stored data.
14. The method as recited in claim 9, wherein between two successive writes of two successive stripes among the plurality of storage devices, the method comprises determining for at least two different storage devices of the plurality of storage devices new distinct values for respective amounts of storage space for user data and corresponding intra-device redundancy data.
15. The method as recited in claim 10, wherein each of the plurality of storage devices comprises solid-state memory.
16. The method as recited in claim 9, wherein each of the first storage device and the second storage device further include a checksum for stored user data of the unit of data, and wherein in response to a read to at least a portion of the unit of data the method further comprises:
utilizing the checksum to validate corresponding read data; and
utilizing intra-device redundancy data to rebuild the corresponding read data in response to detecting the checksum indicates the read data is not valid.
17. A computer readable storage medium storing program instructions, wherein said program instructions are executable to:
receive read and write requests at a data storage subsystem, the data storage subsystem comprising a plurality of storage devices;
identify a unit of data stored in the data storage subsystem, wherein said unit of data is stored across at least a first storage device and a second storage device of the plurality of storage devices, each of the first storage device and the second storage device storing intra-device redundancy data corresponding to the unit of data; and
change an amount of intra-device redundancy data corresponding to the unit of data on only the first storage device.
18. The computer readable storage medium as recited in claim 17, wherein said unit of data is a RAID stripe.
19. The computer readable storage medium as recited in claim 17, wherein said program instructions are further executable to change said amount of intra-device redundancy data stored on the first storage device in response to detecting an indication of a change in reliability of the first storage device.
20. The computer readable storage medium as recited in claim 19, wherein said program instructions are further executable to store data indicative of characteristics of the plurality of storage devices, and wherein said change in reliability is based at least in part on the characteristics.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
1. A separator comprising:
a centrifugal drum including a drum shell having at least one solids discharge nozzle; and
at least one wear protection element on the drum shell in an area of and behind the at least one solids discharge nozzle; and
wherein the at least one wear protection element is constructed as a plate-type body having a channel configured as a discharge channel for a product phase exiting from the centrifugal drum at an angle inclined with respect to a radial direction, the angle being between the radial direction in the area of the at least one discharge nozzle and an orientation of a discharge opening of the at least one discharge nozzle.
2. The separator according to claim 1, wherein the at least one wear protection element is fastened to the drum shell by at least one of the following: a) screws and b) mutually corresponding groove and tongue elements between the drum shell and the at least one wear protection element.
3. The separator according to claim 1, wherein a base of the channel is situated at a distance offset from an outer periphery of the drum shell toward an interior of the centrifugal drum with respect to a discharge opening of the at least one discharge nozzle in the drum shell, and in that the channel is oriented one of a) completely and b) in sections, the sections being one of a) parallel and b) at an angle with respect to a discharge opening of the at least one discharge nozzle.
4. The separator of claim 3, wherein the angle with respect to the discharge opening is less that 30\xb0.
5. The separator according to claim 3, wherein the angle with respect to the discharge opening is less than 20\xb0.
6. The separator according to claim 1, wherein the channel transitions into a ramp.
7. The separator according to claim 6, wherein the ramp, acting as a break edge, extends in a longitudinal direction of the channel over a distance of less than half a length of the channel, such distance being 1 to 10 mm.
8. The separator according to claim 6, wherein a geometry of the transition between the ramp and the channel is at least one of the following: a) curved and b) abrupt.
9. The separator according to claim 6, wherein a geometry of the transition between the ramp and the channel is at least one of the following: a) a circle and b) an exponential function.
10. The separator according to claim 6, wherein an inclination of the ramp with respect to the discharge opening increases in a direction away from the discharge opening.
11. The separator according to claim 6, wherein the ramp of the at least one wear protection elements projects radially beyond an outer periphery of the drum shell.
12. The separator according to claim 6, wherein the ramp is constructed as an undercut break edge.
13. The separator according to claim 1, wherein a first area of the channel adjoins a discharge opening of the at least one discharge nozzle, the first area being parallel to a bore section, and a second area of the channel) is inclined farther toward the radial direction.
14. The separator according to claim 1, wherein a geometry of the at least one wear protection element, as an extension of the channel, is adapted to a curvature of the drum shell.
15. A separator comprising:
a centrifugal drum including a drain shell having at least one solids discharge nozzle; and
at least one wear protection element on the drum shell in an area of and behind the at least one solids discharge nozzle;
wherein the at least one discharge nozzle includes a discharge opening oriented at an angle inclined with respect to a radial direction, and in that the angle, between the radial direction in the area of the at least one discharge nozzle and an orientation of the discharge opening, is equal to or smaller than 90\xb0;
wherein a recess is constructed as an extension of the discharge opening in the drum shell and the recess is configured to receive the at least one wear protection element; and
wherein the at least one wear protection element includes a base plate having tongues as outer edges, the tongues configured to be pushed into two mutually opposite grooves in a lateral base area of the recess.
16. The separator according to claim 15, wherein the angle is between 70 and 85\xb0.
17. The separator according to claim 15, wherein the discharge opening is arranged at an offset distance from an outer periphery of the drum shell toward an interior of the centrifugal drum.
18. The separator according to claim 17, wherein the at least one wear protection element extends from the discharge opening to the outer periphery of the drum shell.
19. The separator according to claim 15, wherein the at least one wear protection element is constructed as a ramp at the at least one discharge nozzle which projects radially beyond the drum shell.
20. A separator comprising:
a centrifugal drum including a drum shell having at least one solids discharge nozzle; and
at least one wear protection element on the drum shell in an area of and behind the at least one solids discharge nozzle; and
further including a sleeve body as part of the at least one discharge nozzle, the sleeve body configured to close off flush with an interior side of the drum shell.
21. The separator according to claim 20, wherein the centrifugal drum has a vertical axis of rotation and at least one of the following: a) a single-cone and b) a double-cone construction.
22. The separator according to claim 20, wherein the at least one solids discharge nozzle is located in an area of the largest diameter of the centrifugal drum and is inserted into the centrifugal drum from an outside of the centrifugal drum.
23. The separator according to claim 20, wherein the at least one wear protection device is constructed as a ramp in the drum shell.
24. The separator according to claim 20, wherein the at least one wear protection element is made of a wear-resistant material that includes one or more of the following: a) steel, b) a hard metal, c) a ceramic material and d) a combination of one or more of a), b), c) and d).
25. The separator according to claim 20, wherein the sleeve body projects slightly into an interior of the centrifugal drum.
26. The separator according to claim 20, wherein the sleeve body is inserted in the radial direction of the centrifugal drum into a radially extending bore of the drum shell.
27. The separator according to claim 20, wherein the sleeve body includes a bore extending from an interior drum space to an exterior drum space and, which sleeve body extends in a first bore section having a first diameter in the radial direction from the interior space to the exterior space and the first bore section changes into a second bore section oriented at an angle with respect to the first bore section and has a smaller second diameter relative to the first diameter.