| 摘要 |
PROBLEM TO BE SOLVED: To prevent the decline of the performance of the entire system by not obstructing the execution of a transaction for requesting access to another page. SOLUTION: In the case of finding a buffer, whether or not a desired butter is present is judged, and when the buffer for the page is absent in a buffer frame chain, a butter lock chain is inspected while holding the exclusive latch of a buffer hash anchor. Whether or not a desired page is present is judged by performing an inspection, and when information for the desired page is absent in the butter lock chain, it is indicated that the other transaction for requesting the pertinent page is absent at present and the transaction is allocated to the buffer. In order to make the request of the other transaction standby until an arithmetic operation for reading the page from a disk is completed, a butter lock entry for the pertinent page is newly constituted and registered in the buffer lock chain.
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