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Code Activity

1. Vacuum is updated for MVCC.

Browse Source 
2. Much faster btree tuples deletion in the case when first on page
   index tuple is deleted (no movement to the left page(s)).
3. Remember blkno of new root page in BTPageOpaque of
   left/right siblings when root page is splitted.
This commit is contained in:
Vadim B. Mikheev
1999-03-28 20:32:42 +00:00
parent d4ed17842a
commit fdf6be80f9
16 changed files with 802 additions and 352 deletions
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73
src/backend/storage/ipc/shmem.c
View File

@@ -7,7 +7,7 @@
*
*
* IDENTIFICATION
* $Header: /cvsroot/pgsql/src/backend/storage/ipc/shmem.c,v 1.37 1999/02/22 06:16:48 tgl Exp $
* $Header: /cvsroot/pgsql/src/backend/storage/ipc/shmem.c,v 1.38 1999/03/28 20:32:22 vadim Exp $
*
*-------------------------------------------------------------------------
*/
@@ -636,12 +636,13 @@ TransactionIdIsInProgress(TransactionId xid)
Snapshot
GetSnapshotData(bool serializable)
{
Snapshot snapshot = (Snapshot) malloc(sizeof(SnapshotData));
ShmemIndexEnt *result;
PROC *proc;
TransactionId cid = GetCurrentTransactionId();
uint32 count = 0;
uint32 have = 32;
Snapshot snapshot = (Snapshot) malloc(sizeof(SnapshotData));
ShmemIndexEnt *result;
PROC *proc;
TransactionId cid = GetCurrentTransactionId();
TransactionId xid;
uint32 count = 0;
uint32 have = 32;
Assert(ShmemIndex);
@@ -669,19 +670,20 @@ GetSnapshotData(bool serializable)
strncmp(result->key, "PID ", 4) != 0)
continue;
proc = (PROC *) MAKE_PTR(result->location);
if (proc == MyProc || proc->xid < FirstTransactionId)
xid = proc->xid; /* we don't use spin-locking in xact.c ! */
if (proc == MyProc || xid < FirstTransactionId)
continue;
if (proc->xid < snapshot->xmin)
snapshot->xmin = proc->xid;
else if (proc->xid > snapshot->xmax)
snapshot->xmax = proc->xid;
if (xid < snapshot->xmin)
snapshot->xmin = xid;
else if (xid > snapshot->xmax)
snapshot->xmax = xid;
if (have == 0)
{
snapshot->xip = (TransactionId *) realloc(snapshot->xip,
(count + 32) * sizeof(TransactionId));
have = 32;
}
snapshot->xip[count] = proc->xid;
snapshot->xip[count] = xid;
have--;
count++;
}
@@ -692,3 +694,48 @@ GetSnapshotData(bool serializable)
elog(ERROR, "GetSnapshotData: ShmemIndex corrupted");
return NULL;
}
/*
* GetXmaxRecent -- returns oldest transaction that was running
* when all current transaction was started.
* It's used by vacuum to decide what deleted
* tuples must be preserved in a table.
*
* And yet another strange func for this place... - vadim 03/18/99
*/
void
GetXmaxRecent(TransactionId *XmaxRecent)
{
ShmemIndexEnt *result;
PROC *proc;
TransactionId xmin;
Assert(ShmemIndex);
ReadNewTransactionId(XmaxRecent);
SpinAcquire(ShmemIndexLock);
hash_seq((HTAB *) NULL);
while ((result = (ShmemIndexEnt *) hash_seq(ShmemIndex)) != NULL)
{
if (result == (ShmemIndexEnt *) TRUE)
{
SpinRelease(ShmemIndexLock);
return;
}
if (result->location == INVALID_OFFSET ||
strncmp(result->key, "PID ", 4) != 0)
continue;
proc = (PROC *) MAKE_PTR(result->location);
xmin = proc->xmin; /* we don't use spin-locking in xact.c ! */
if (proc == MyProc || xmin < FirstTransactionId)
continue;
if (xmin < *XmaxRecent)
*XmaxRecent = xmin;
}
SpinRelease(ShmemIndexLock);
elog(ERROR, "GetXmaxRecent: ShmemIndex corrupted");
return NULL;
}