mirror of
https://github.com/versity/scoutfs.git
synced 2026-04-14 10:57:00 +00:00
09fe4fddd4
Currently we maintain a single LRU list of cluster locks and every time we acquire a cluster lock we move it to the head of the LRU, creating significant contention acquiring the spinlock that protects the LRU list. This moves to two LRU lists, a list of cluster locks ready to be reclaimed and one for locks that are in active use. We mark locks with which list they're on and only move them to the active list if they're on the reclaim list. We track imbalance between the two lists so that they're always roughly the same size. This removes contention maintaining a precise LRU amongst a set of active cluster locks. It doesn't address contention creating or removing locks, which are already very expensive operations. It also loses strict ordering by access time. Reclaim has to make it through the oldest half of locks before getting to the newer half, though there is no guaranteed ordering amogst the newest half. Signed-off-by: Zach Brown <zab@versity.com> Signed-off-by: Chris Kirby <ckirby@versity.com>