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pgindent run for 8.3.

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This commit is contained in:
Bruce Momjian
2007-11-15 21:14:46 +00:00
parent 3adc760fb9
commit fdf5a5efb7
486 changed files with 10044 additions and 9664 deletions
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58
src/backend/access/heap/syncscan.c
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@ -4,7 +4,7 @@
* heap scan synchronization support
*
* When multiple backends run a sequential scan on the same table, we try
* to keep them synchronized to reduce the overall I/O needed. The goal is
* to keep them synchronized to reduce the overall I/O needed. The goal is
* to read each page into shared buffer cache only once, and let all backends
* that take part in the shared scan process the page before it falls out of
* the cache.
@ -26,7 +26,7 @@
* don't want such queries to slow down others.
*
* There can realistically only be a few large sequential scans on different
* tables in progress at any time. Therefore we just keep the scan positions
* tables in progress at any time. Therefore we just keep the scan positions
* in a small LRU list which we scan every time we need to look up or update a
* scan position. The whole mechanism is only applied for tables exceeding
* a threshold size (but that is not the concern of this module).
@ -40,7 +40,7 @@
* Portions Copyright (c) 1994, Regents of the University of California
*
* IDENTIFICATION
* $PostgreSQL: pgsql/src/backend/access/heap/syncscan.c,v 1.1 2007/06/08 18:23:52 tgl Exp $
* $PostgreSQL: pgsql/src/backend/access/heap/syncscan.c,v 1.2 2007/11/15 21:14:32 momjian Exp $
*
*-------------------------------------------------------------------------
*/
@ -52,7 +52,7 @@
/* GUC variables */
#ifdef TRACE_SYNCSCAN
bool trace_syncscan = false;
bool trace_syncscan = false;
#endif
@ -89,21 +89,21 @@ typedef struct ss_scan_location_t
{
RelFileNode relfilenode; /* identity of a relation */
BlockNumber location; /* last-reported location in the relation */
} ss_scan_location_t;
} ss_scan_location_t;
typedef struct ss_lru_item_t
{
struct ss_lru_item_t *prev;
struct ss_lru_item_t *next;
ss_scan_location_t location;
} ss_lru_item_t;
struct ss_lru_item_t *prev;
struct ss_lru_item_t *next;
ss_scan_location_t location;
} ss_lru_item_t;
typedef struct ss_scan_locations_t
{
ss_lru_item_t *head;
ss_lru_item_t *tail;
ss_lru_item_t items[1]; /* SYNC_SCAN_NELEM items */
} ss_scan_locations_t;
ss_lru_item_t *head;
ss_lru_item_t *tail;
ss_lru_item_t items[1]; /* SYNC_SCAN_NELEM items */
} ss_scan_locations_t;
#define SizeOfScanLocations(N) offsetof(ss_scan_locations_t, items[N])
@ -112,7 +112,7 @@ static ss_scan_locations_t *scan_locations;
/* prototypes for internal functions */
static BlockNumber ss_search(RelFileNode relfilenode,
BlockNumber location, bool set);
BlockNumber location, bool set);
/*
@ -130,8 +130,8 @@ SyncScanShmemSize(void)
void
SyncScanShmemInit(void)
{
int i;
bool found;
int i;
bool found;
scan_locations = (ss_scan_locations_t *)
ShmemInitStruct("Sync Scan Locations List",
@ -186,20 +186,20 @@ SyncScanShmemInit(void)
static BlockNumber
ss_search(RelFileNode relfilenode, BlockNumber location, bool set)
{
ss_lru_item_t *item;
ss_lru_item_t *item;
item = scan_locations->head;
for (;;)
{
bool match;
bool match;
match = RelFileNodeEquals(item->location.relfilenode, relfilenode);
if (match || item->next == NULL)
{
/*
* If we reached the end of list and no match was found,
* take over the last entry
* If we reached the end of list and no match was found, take over
* the last entry
*/
if (!match)
{
@ -242,7 +242,7 @@ ss_search(RelFileNode relfilenode, BlockNumber location, bool set)
* relation, or 0 if no valid location is found.
*
* We expect the caller has just done RelationGetNumberOfBlocks(), and
* so that number is passed in rather than computing it again. The result
* so that number is passed in rather than computing it again. The result
* is guaranteed less than relnblocks (assuming that's > 0).
*/
BlockNumber
@ -257,8 +257,8 @@ ss_get_location(Relation rel, BlockNumber relnblocks)
/*
* If the location is not a valid block number for this scan, start at 0.
*
* This can happen if for instance a VACUUM truncated the table
* since the location was saved.
* This can happen if for instance a VACUUM truncated the table since the
* location was saved.
*/
if (startloc >= relnblocks)
startloc = 0;
@ -294,12 +294,12 @@ ss_report_location(Relation rel, BlockNumber location)
#endif
/*
* To reduce lock contention, only report scan progress every N pages.
* For the same reason, don't block if the lock isn't immediately
* available. Missing a few updates isn't critical, it just means that a
* new scan that wants to join the pack will start a little bit behind the
* head of the scan. Hopefully the pages are still in OS cache and the
* scan catches up quickly.
* To reduce lock contention, only report scan progress every N pages. For
* the same reason, don't block if the lock isn't immediately available.
* Missing a few updates isn't critical, it just means that a new scan
* that wants to join the pack will start a little bit behind the head of
* the scan. Hopefully the pages are still in OS cache and the scan
* catches up quickly.
*/
if ((location % SYNC_SCAN_REPORT_INTERVAL) == 0)
{