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Diffstat (limited to 'src/backend/utils/time/snapmgr.c')
-rw-r--r--src/backend/utils/time/snapmgr.c61
1 files changed, 30 insertions, 31 deletions
diff --git a/src/backend/utils/time/snapmgr.c b/src/backend/utils/time/snapmgr.c
index f8a2a83b88c..8a1c9932e54 100644
--- a/src/backend/utils/time/snapmgr.c
+++ b/src/backend/utils/time/snapmgr.c
@@ -78,16 +78,15 @@ typedef struct OldSnapshotControlData
* Variables for old snapshot handling are shared among processes and are
* only allowed to move forward.
*/
- slock_t mutex_current; /* protect current_timestamp */
+ slock_t mutex_current; /* protect current_timestamp */
int64 current_timestamp; /* latest snapshot timestamp */
- slock_t mutex_latest_xmin; /* protect latest_xmin
- * and next_map_update
- */
- TransactionId latest_xmin; /* latest snapshot xmin */
- int64 next_map_update; /* latest snapshot valid up to */
- slock_t mutex_threshold; /* protect threshold fields */
+ slock_t mutex_latest_xmin; /* protect latest_xmin and
+ * next_map_update */
+ TransactionId latest_xmin; /* latest snapshot xmin */
+ int64 next_map_update; /* latest snapshot valid up to */
+ slock_t mutex_threshold; /* protect threshold fields */
int64 threshold_timestamp; /* earlier snapshot is old */
- TransactionId threshold_xid; /* earlier xid may be gone */
+ TransactionId threshold_xid; /* earlier xid may be gone */
/*
* Keep one xid per minute for old snapshot error handling.
@@ -117,11 +116,11 @@ typedef struct OldSnapshotControlData
*
* Persistence is not needed.
*/
- int head_offset; /* subscript of oldest tracked time */
- int64 head_timestamp; /* time corresponding to head xid */
- int count_used; /* how many slots are in use */
+ int head_offset; /* subscript of oldest tracked time */
+ int64 head_timestamp; /* time corresponding to head xid */
+ int count_used; /* how many slots are in use */
TransactionId xid_by_minute[FLEXIBLE_ARRAY_MEMBER];
-} OldSnapshotControlData;
+} OldSnapshotControlData;
static volatile OldSnapshotControlData *oldSnapshotControl;
@@ -709,8 +708,8 @@ UpdateActiveSnapshotCommandId(void)
/*
* Don't allow modification of the active snapshot during parallel
- * operation. We share the snapshot to worker backends at the beginning of
- * parallel operation, so any change to the snapshot can lead to
+ * operation. We share the snapshot to worker backends at the beginning
+ * of parallel operation, so any change to the snapshot can lead to
* inconsistencies. We have other defenses against
* CommandCounterIncrement, but there are a few places that call this
* directly, so we put an additional guard here.
@@ -1634,7 +1633,7 @@ TransactionIdLimitedForOldSnapshots(TransactionId recentXmin,
}
ts = AlignTimestampToMinuteBoundary(ts)
- - (old_snapshot_threshold * USECS_PER_MINUTE);
+ - (old_snapshot_threshold * USECS_PER_MINUTE);
/* Check for fast exit without LW locking. */
SpinLockAcquire(&oldSnapshotControl->mutex_threshold);
@@ -1660,14 +1659,14 @@ TransactionIdLimitedForOldSnapshots(TransactionId recentXmin,
if (oldSnapshotControl->count_used > 0
&& ts >= oldSnapshotControl->head_timestamp)
{
- int offset;
+ int offset;
offset = ((ts - oldSnapshotControl->head_timestamp)
/ USECS_PER_MINUTE);
if (offset > oldSnapshotControl->count_used - 1)
offset = oldSnapshotControl->count_used - 1;
offset = (oldSnapshotControl->head_offset + offset)
- % OLD_SNAPSHOT_TIME_MAP_ENTRIES;
+ % OLD_SNAPSHOT_TIME_MAP_ENTRIES;
xlimit = oldSnapshotControl->xid_by_minute[offset];
if (NormalTransactionIdFollows(xlimit, recentXmin))
@@ -1715,8 +1714,8 @@ MaintainOldSnapshotTimeMapping(int64 whenTaken, TransactionId xmin)
ts = AlignTimestampToMinuteBoundary(whenTaken);
/*
- * Keep track of the latest xmin seen by any process. Update mapping
- * with a new value when we have crossed a bucket boundary.
+ * Keep track of the latest xmin seen by any process. Update mapping with
+ * a new value when we have crossed a bucket boundary.
*/
SpinLockAcquire(&oldSnapshotControl->mutex_latest_xmin);
latest_xmin = oldSnapshotControl->latest_xmin;
@@ -1747,7 +1746,7 @@ MaintainOldSnapshotTimeMapping(int64 whenTaken, TransactionId xmin)
if (whenTaken < 0)
{
elog(DEBUG1,
- "MaintainOldSnapshotTimeMapping called with negative whenTaken = %ld",
+ "MaintainOldSnapshotTimeMapping called with negative whenTaken = %ld",
(long) whenTaken);
return;
}
@@ -1789,10 +1788,10 @@ MaintainOldSnapshotTimeMapping(int64 whenTaken, TransactionId xmin)
* USECS_PER_MINUTE)))
{
/* existing mapping; advance xid if possible */
- int bucket = (oldSnapshotControl->head_offset
- + ((ts - oldSnapshotControl->head_timestamp)
- / USECS_PER_MINUTE))
- % OLD_SNAPSHOT_TIME_MAP_ENTRIES;
+ int bucket = (oldSnapshotControl->head_offset
+ + ((ts - oldSnapshotControl->head_timestamp)
+ / USECS_PER_MINUTE))
+ % OLD_SNAPSHOT_TIME_MAP_ENTRIES;
if (TransactionIdPrecedes(oldSnapshotControl->xid_by_minute[bucket], xmin))
oldSnapshotControl->xid_by_minute[bucket] = xmin;
@@ -1800,8 +1799,8 @@ MaintainOldSnapshotTimeMapping(int64 whenTaken, TransactionId xmin)
else
{
/* We need a new bucket, but it might not be the very next one. */
- int advance = ((ts - oldSnapshotControl->head_timestamp)
- / USECS_PER_MINUTE);
+ int advance = ((ts - oldSnapshotControl->head_timestamp)
+ / USECS_PER_MINUTE);
oldSnapshotControl->head_timestamp = ts;
@@ -1815,14 +1814,14 @@ MaintainOldSnapshotTimeMapping(int64 whenTaken, TransactionId xmin)
else
{
/* Store the new value in one or more buckets. */
- int i;
+ int i;
for (i = 0; i < advance; i++)
{
if (oldSnapshotControl->count_used == OLD_SNAPSHOT_TIME_MAP_ENTRIES)
{
/* Map full and new value replaces old head. */
- int old_head = oldSnapshotControl->head_offset;
+ int old_head = oldSnapshotControl->head_offset;
if (old_head == (OLD_SNAPSHOT_TIME_MAP_ENTRIES - 1))
oldSnapshotControl->head_offset = 0;
@@ -1833,9 +1832,9 @@ MaintainOldSnapshotTimeMapping(int64 whenTaken, TransactionId xmin)
else
{
/* Extend map to unused entry. */
- int new_tail = (oldSnapshotControl->head_offset
- + oldSnapshotControl->count_used)
- % OLD_SNAPSHOT_TIME_MAP_ENTRIES;
+ int new_tail = (oldSnapshotControl->head_offset
+ + oldSnapshotControl->count_used)
+ % OLD_SNAPSHOT_TIME_MAP_ENTRIES;
oldSnapshotControl->count_used++;
oldSnapshotControl->xid_by_minute[new_tail] = xmin;
generated by cgit v1.2.3 (git 2.25.1) at 2025-05-20 06:31:20 +0000