| From: | Heikki Linnakangas <heikki(at)enterprisedb(dot)com> |
|---|---|
| To: | rancpine cui <rancpine(at)gmail(dot)com> |
| Cc: | pgsql-hackers(at)postgresql(dot)org |
| Subject: | Re: How does the partitioned lock manager works? |
| Date: | 2007-04-27 09:01:58 |
| Message-ID: | 4631BC06.5000304@enterprisedb.com |
| Views: | Raw Message | Whole Thread | Download mbox | Resend email |
| Thread: | |
| Lists: | pgsql-hackers |
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
| From | Date | Subject | |
|---|---|---|---|
| Next Message | Hans-Juergen Schoenig | 2007-04-27 10:56:27 | Re: Hi, I wanto joinin the developer group of postgresql |
| Previous Message | Dave Page | 2007-04-27 08:53:10 | Windows support - PostgreSQL 8.0 and 8.1 |