* Increase LRU latches. By default, most Oracle systems have only 8 to 32 LRU chain latches. LRU concurrency can be increased by adding latches, which means increasing the hidden parameter _db_block_lru_latches. This can be especially effective if you have a multigigabyte buffer cache.

* Use multiple buffer pools. A creative strategy to take some of the strain off the main LRU chains is to implement the keep and recycle pools. All buffer pools can have their number of LRU chain latches increased. They also use the touch-count algorithm, and therefore have similar touch count instance parameters, such as _db_percent_hot_keep.

* Adjust touch count instance parameters. Table 6-3 summarizes the available touch count parameters. But be warned: the parameters have very small values, like 1 and 2. Therefore, even a switch from 1 to 2 is a relatively massive change that could easily have unintended consequences. I would consider adjusting the touch count parameters only as a last resort and after testing; otherwise, you'll just be guessing.