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Concurrency for GiST

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- full concurrency for insert/update/select/vacuum:
        - select and vacuum never locks more than one page simultaneously
        - select (gettuple) hasn't any lock across it's calls
        - insert never locks more than two page simultaneously:
                - during search of leaf to insert it locks only one page
                  simultaneously
                - while walk upward to the root it locked only parent (may be
                  non-direct parent) and child. One of them X-lock, another may
                  be S- or X-lock
- 'vacuum full' locks index
- improve gistgetmulti
- simplify XLOG records

Fix bug in index_beginscan_internal: LockRelation may clean
  rd_aminfo structure, so move GET_REL_PROCEDURE after LockRelation
This commit is contained in:
Teodor Sigaev
2005-06-27 12:45:23 +00:00
parent c3be085ab7
commit e8cab5fe49
12 changed files with 994 additions and 598 deletions
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48
src/backend/access/gist/gistutil.c
View File

@ -8,7 +8,7 @@
* Portions Copyright (c) 1994, Regents of the University of California
*
* IDENTIFICATION
* $PostgreSQL: pgsql/src/backend/access/gist/gistutil.c,v 1.2 2005/06/20 10:29:36 teodor Exp $
* $PostgreSQL: pgsql/src/backend/access/gist/gistutil.c,v 1.3 2005/06/27 12:45:22 teodor Exp $
*-------------------------------------------------------------------------
*/
#include "postgres.h"
@ -803,8 +803,12 @@ GISTInitBuffer(Buffer b, uint32 f)
page = BufferGetPage(b);
PageInit(page, pageSize, sizeof(GISTPageOpaqueData));
opaque = (GISTPageOpaque) PageGetSpecialPointer(page);
opaque = GistPageGetOpaque(page);
opaque->flags = f;
opaque->nsplited = 0;
opaque->level = 0;
opaque->rightlink = InvalidBlockNumber;
memset( &(opaque->nsn), 0, sizeof(GistNSN) );
}
void
@ -856,30 +860,38 @@ gistUserPicksplit(Relation r, GistEntryVector *entryvec, GIST_SPLITVEC *v,
}
Buffer
gistReadBuffer(Relation r, BlockNumber blkno) {
gistNewBuffer(Relation r) {
Buffer buffer = InvalidBuffer;
bool needLock;
while(true) {
BlockNumber blkno = GetFreeIndexPage(&r->rd_node);
if (blkno == InvalidBlockNumber)
break;
if ( blkno != P_NEW ) {
buffer = ReadBuffer(r, blkno);
} else {
Page page;
while(true) {
blkno = GetFreeIndexPage(&r->rd_node);
if (blkno == InvalidBlockNumber)
break;
buffer = ReadBuffer(r, blkno);
page = BufferGetPage(buffer);
if ( ConditionalLockBuffer(buffer) ) {
Page page = BufferGetPage(buffer);
if ( GistPageIsDeleted( page ) ) {
GistPageSetNonDeleted( page );
return buffer;
}
ReleaseBuffer( buffer );
} else
LockBuffer(buffer, GIST_UNLOCK);
}
buffer = ReadBuffer(r, P_NEW);
ReleaseBuffer( buffer );
}
needLock = !RELATION_IS_LOCAL(r);
if (needLock)
LockRelationForExtension(r, ExclusiveLock);
buffer = ReadBuffer(r, P_NEW);
LockBuffer(buffer, GIST_EXCLUSIVE);
if (needLock)
UnlockRelationForExtension(r, ExclusiveLock);
return buffer;
}