database/postgres
1
0
Fork 0
mirror of https://github.com/postgres/postgres.git synced 2025-11-16 15:02:33 +03:00
Code Activity

Pgindent run for 8.0.

Browse Source
This commit is contained in:
Bruce Momjian
2004-08-29 05:07:03 +00:00
parent 90cb9c3051
commit b6b71b85bc
527 changed files with 20550 additions and 18283 deletions
Download Patch File Download Diff File Expand all files Collapse all files

31
src/backend/access/nbtree/nbtpage.c
View File

@@ -9,7 +9,7 @@
*
*
* IDENTIFICATION
* $PostgreSQL: pgsql/src/backend/access/nbtree/nbtpage.c,v 1.79 2004/08/29 04:12:21 momjian Exp $
* $PostgreSQL: pgsql/src/backend/access/nbtree/nbtpage.c,v 1.80 2004/08/29 05:06:40 momjian Exp $
*
* NOTES
* Postgres btree pages look like ordinary relation pages. The opaque
@@ -276,8 +276,8 @@ _bt_getroot(Relation rel, int access)
rootlevel = metad->btm_fastlevel;
/*
* We are done with the metapage; arrange to release it via
* first _bt_relandgetbuf call
* We are done with the metapage; arrange to release it via first
* _bt_relandgetbuf call
*/
rootbuf = metabuf;
@@ -368,8 +368,8 @@ _bt_gettrueroot(Relation rel)
rootlevel = metad->btm_level;
/*
* We are done with the metapage; arrange to release it via
* first _bt_relandgetbuf call
* We are done with the metapage; arrange to release it via first
* _bt_relandgetbuf call
*/
rootbuf = metabuf;
@@ -433,21 +433,22 @@ _bt_getbuf(Relation rel, BlockNumber blkno, int access)
* page could have been re-used between the time the last VACUUM
* scanned it and the time the VACUUM made its FSM updates.)
*
* In fact, it's worse than that: we can't even assume that it's
* safe to take a lock on the reported page. If somebody else
* has a lock on it, or even worse our own caller does, we could
* In fact, it's worse than that: we can't even assume that it's safe
* to take a lock on the reported page. If somebody else has a
* lock on it, or even worse our own caller does, we could
* deadlock. (The own-caller scenario is actually not improbable.
* Consider an index on a serial or timestamp column. Nearly all
* splits will be at the rightmost page, so it's entirely likely
* that _bt_split will call us while holding a lock on the page most
* recently acquired from FSM. A VACUUM running concurrently with
* the previous split could well have placed that page back in FSM.)
* that _bt_split will call us while holding a lock on the page
* most recently acquired from FSM. A VACUUM running concurrently
* with the previous split could well have placed that page back
* in FSM.)
*
* To get around that, we ask for only a conditional lock on the
* reported page. If we fail, then someone else is using the page,
* and we may reasonably assume it's not free. (If we happen to be
* wrong, the worst consequence is the page will be lost to use till
* the next VACUUM, which is no big problem.)
* reported page. If we fail, then someone else is using the
* page, and we may reasonably assume it's not free. (If we
* happen to be wrong, the worst consequence is the page will be
* lost to use till the next VACUUM, which is no big problem.)
*/
for (;;)
{