Manfred Spraul wrote: > Bruce Momjian wrote: > >>>Anyone see an attack path here? >>> >>> >> >>Should we have one lock per hash bucket rather than one for the entire >>hash? >> >> > That's the simple part. The problem is the aging strategy: we need a > strategy that doesn't rely on a global list that's updated after every > lookup. If I understand the ARC code correctly, there is a > STRAT_MRU_INSERT(cdb, STRAT_LIST_T2) that happen in every lookup.
Moving the Cache Directory Block (cdb) on a hit to the MRU position of the appropriate queue "is the bookkeeping" of this strategy. The whole algorithm is based on it, and I don't see yet how to avoid that without opening a huge can of worms that look like deadlocks. But I'll think about it for a while. Jan -- #======================================================================# # It's easier to get forgiveness for being wrong than for being right. # # Let's break this rule - forgive me. # #================================================== [EMAIL PROTECTED] # ---------------------------(end of broadcast)--------------------------- TIP 7: don't forget to increase your free space map settings
