Re: How does the partitioned lock manager works?

rancpine cui wrote:
>    When the lock manager's data structures were split into "partitions",
> how many such data structures can one partition control? 

The number of partitions is 16 (NUM_LOCK_PARTITIONS). The total size of 
the lock hash table is max_locks_per_xact * (max_connections + 
max_prepared_xacts). So the number of "lock slots" per partition is 
(max_locks_per_xact * (max_connections + 
max_prepared_xacts))/NUM_LOCK_PARTITIONS.

> Since we use
> LOCKTAG's hash value to decide the partition which the lock should in, can
> all locks be split into ONE partition?

In theory, yes. It's extremely unlikely to happen in practice.

--   Heikki Linnakangas  EnterpriseDB   http://www.enterprisedb.com