Randomized page weights for optimizing buffer pool page reuse

摘要

In general, the disclosure is directed to techniques for choosing which pages to evict from the buffer pool to make room for caching additional pages in the context of a database table scan. A buffer pool is maintained in memory. A fraction of pages of a table to persist in the buffer pool are determined. A random number is generated as a decimal value of 0 to 1 for each page of the table cached in the buffer pool. If the random number generated for a page is less than the fraction, the page is persisted in the buffer pool. If the random number generated for a page is greater than the fraction, the page is included as a candidate for eviction from the buffer pool.

主权项

1. A computer-implemented method comprising:
maintaining a buffer pool in memory; determining a fraction of pages of a table to persist in the buffer pool; generating a random number as a decimal value in a range of 0 to 1 for each page of the table persisted in the buffer pool; if the random number generated for a particular page is less than the fraction, persisting the particular page in the buffer pool; and if the random number generated for the particular page is greater than the fraction, including the particular page as a candidate for eviction from the buffer pool.