A technique for caching evidence for answering questions in a cache memory of a data processing system (that is configured to answer questions) includes receiving a first question. The first question is analyzed to identify a first set of characteristics of the first question. A first set of evidence for answering the first question is loaded into the cache memory. A second question is received. The second question is analyzed to identify a second set of characteristics of the second question. A portion of the first set of evidence, whose expected usage in answering the second question is below a determined threshold, is unloaded from the cache memory.
Please help me write a proper abstract based on the patent claims. CLAIM: 1. A method for caching evidence for answering questions in a cache memory of a data processing system that is configured to answer questions, comprising: receiving, by the data processing system, a first question; analyzing, by the data processing system, the first question to identify a first set of characteristics of the first question; loading, by the data processing system, a first set of evidence into the cache memory of the data processing system for answering the first question; receiving, by the data processing system, a second question; analyzing, by the data processing system, the second question to identify a second set of characteristics of the second question; and unloading from the cache memory, by the data processing system, a portion of the first set of evidence whose expected usage in answering the second question is below a determined threshold. 2. The method of claim 1, wherein the unloading, by the data processing system, a portion of the first set of evidence is performed at a rate that is based on a relevance of the first set of characteristics to the second set of characteristics. 3. The method of claim 1, wherein the first set of characteristics and the second set of characteristics each include a question type, an evidence size, primary search attributes, and an evidence score that are respectively associated with the first and second questions. 4. The method of claim 1, further comprising: loading additional evidence for a hypothesis related to one of the first and second questions into the cache memory when another question is not received. 5. The method of claim 1, further comprising comparing the first set of characteristics to the second set of characteristics to determine the expected usage for the first set of evidence. 6. The method of claim 1, wherein the cache memory is shared between processors of a node and the data processing system is a high performance computing system that includes multiple nodes. 7. The method of claim 1, wherein the unloading, by the data processing system, a portion of the first set of evidence is performed at a rate that is based on a relevance of the first set of characteristics to subsequent question characteristics. 8. A computer program product for managing cache memory of a question answering system, the computer program product comprising: a computer-readable storage device; and computer-readable program code embodied on the computer-readable storage device, wherein the computer-readable program code, when executed by a data processing system, causes the data processing system to: receive a first question; analyze the first question to identify a first set of characteristics of the first question; load a first set of evidence into the cache memory of the data processing system for answering the first question; receive a second question; analyze the second question to identify a second set of characteristics of the second question; and unload from the cache memory a portion of the first set of evidence whose expected usage in answering the second question is below a determined level. 9. The computer program product of claim 8, wherein the unloading a portion of the first set of evidence is performed at a rate that is based on a relevance of the first set of characteristics to the second set of characteristics. 10. The computer program product of claim 8, wherein the first set of characteristics and the second set of characteristics each include a question type, an evidence size, primary search attributes, and an evidence score that are respectively associated with the first and second questions. 11. The computer program product of claim 8, wherein the computer-readable program code, when executed by the data processing system, is further configured to cause the data processing system to load additional evidence for a hypothesis related to one of the first and second questions into the cache memory when another question is not received. 12. The computer program product of claim 8, further comprising comparing the first set of characteristics to the second set of characteristics to determine the expected usage for the first set of evidence. 13. The computer program product of claim 8, wherein the cache memory is shared between processors of a node of a high performance computing system that includes multiple nodes. 14. The computer program product of claim 8, wherein the unloading a portion of the first set of evidence is performed at a rate that is based on a relevance of the first set of characteristics to subsequent question characteristics. 15. A data processing system, comprising: a cache memory; and a processor coupled to the cache memory, wherein the processor is configured to: receive a first question; analyze the first question to identify a first set of characteristics of the first question; load a first set of evidence into the cache memory for answering the first question; receive a second question; analyze the second question to identify a second set of characteristics of the second question; and unload from the cache memory a portion of the first set of evidence whose expected usage in answering the second question is below a determined level. 16. The data processing system of claim 15, wherein the unloading a portion of the first set of evidence is performed at a rate that is based on a relevance of the first set of characteristics to the second set of characteristics. 17. The data processing system of claim 15, wherein the first set of characteristics and the second set of characteristics each include a question type, an evidence size, primary search attributes, and an evidence score that are respectively associated with the first and second questions. 18. The data processing system of claim 15, wherein the processor is further configured to load additional evidence for a hypothesis related to one of the first and second questions into the cache memory when another question is not received. 19. The data processing system of claim 15, wherein the processor is further configured to compare the first set of characteristics to the second set of characteristics to determine the expected usage for the first set of evidence. 20. The data processing system of claim 15, wherein the cache memory is shared between processors of a node and the data processing system is a high performance computing system that includes multiple nodes.