Dr. Sun,

I know you have explained this in class, but just to make sure I understood it correctly, when there are multiple transactions that are pinned to a page in the buffer pool, we only record the first pin time for FIFO and first unpin time for LRU, is that correct? Thank you in advance,

cysun wrote:

Yes for FIFO. For LRU there's only one unpin time.

I see. So unpinning is distinguished from decrementing the pincount.

Thank you!