Movatterモバイル変換

[0]ホーム
URL:

Skip to content

Navigation Menu

Sign in
Appearance settings

Search code, repositories, users, issues, pull requests...

Provide feedback

We read every piece of feedback, and take your input very seriously.

Saved searches

Use saved searches to filter your results more quickly

 Sign up
Appearance settings

Commit89395bf

Browse files
committed
Improve gist XLOG code to follow the coding rules needed to prevent
torn-page problems. This introduces some issues of its own, mainlythat there are now some critical sections of unreasonably broad scope,but it's a step forward anyway. Further cleanup will require somecode refactoring that I'd prefer to get Oleg and Teodor involved in.
1 parent4243f23 commit89395bf

File tree

4 files changed

+229
-260
lines changed

4 files changed

+229
-260
lines changed

‎src/backend/access/gist/gist.c‎

Lines changed: 53 additions & 52 deletions
Original file line numberDiff line numberDiff line change
@@ -8,7 +8,7 @@
88
* Portions Copyright (c) 1994, Regents of the University of California
99
*
1010
* IDENTIFICATION
11-
* $PostgreSQL: pgsql/src/backend/access/gist/gist.c,v 1.129 2006/03/05 15:58:20 momjian Exp $
11+
* $PostgreSQL: pgsql/src/backend/access/gist/gist.c,v 1.130 2006/03/30 23:03:09 tgl Exp $
1212
*
1313
*-------------------------------------------------------------------------
1414
*/
@@ -90,6 +90,7 @@ gistbuild(PG_FUNCTION_ARGS)
9090
doublereltuples;
9191
GISTBuildStatebuildstate;
9292
Bufferbuffer;
93+
Pagepage;
9394

9495
/*
9596
* We expect to be called exactly once for any index relation. If that's
@@ -104,33 +105,33 @@ gistbuild(PG_FUNCTION_ARGS)
104105

105106
/* initialize the root page */
106107
buffer=gistNewBuffer(index);
108+
Assert(BufferGetBlockNumber(buffer)==GIST_ROOT_BLKNO);
109+
page=BufferGetPage(buffer);
110+
111+
START_CRIT_SECTION();
112+
107113
GISTInitBuffer(buffer,F_LEAF);
108114
if (!index->rd_istemp)
109115
{
110116
XLogRecPtrrecptr;
111117
XLogRecDatardata;
112-
Pagepage;
113118

114-
rdata.buffer=InvalidBuffer;
115119
rdata.data= (char*)&(index->rd_node);
116120
rdata.len=sizeof(RelFileNode);
121+
rdata.buffer=InvalidBuffer;
117122
rdata.next=NULL;
118123

119-
page=BufferGetPage(buffer);
120-
121-
START_CRIT_SECTION();
122-
123124
recptr=XLogInsert(RM_GIST_ID,XLOG_GIST_CREATE_INDEX,&rdata);
124125
PageSetLSN(page,recptr);
125126
PageSetTLI(page,ThisTimeLineID);
126-
127-
END_CRIT_SECTION();
128127
}
129128
else
130-
PageSetLSN(BufferGetPage(buffer),XLogRecPtrForTemp);
129+
PageSetLSN(page,XLogRecPtrForTemp);
131130
LockBuffer(buffer,GIST_UNLOCK);
132131
WriteBuffer(buffer);
133132

133+
END_CRIT_SECTION();
134+
134135
/* build the index */
135136
buildstate.numindexattrs=indexInfo->ii_NumIndexAttrs;
136137
buildstate.indtuples=0;
@@ -305,13 +306,27 @@ gistplacetopage(GISTInsertState *state, GISTSTATE *giststate)
305306
boolis_splitted= false;
306307
boolis_leaf= (GistPageIsLeaf(state->stack->page)) ? true : false;
307308

309+
/*
310+
* XXX this code really ought to work by locking, but not modifying,
311+
* all the buffers it needs; then starting a critical section; then
312+
* modifying the buffers in an already-determined way and writing an
313+
* XLOG record to reflect that. Since it doesn't, we've got to put
314+
* a critical section around the entire process, which is horrible
315+
* from a robustness point of view.
316+
*/
317+
START_CRIT_SECTION();
308318

309319
if (!is_leaf)
310320

311321
/*
312322
* This node's key has been modified, either because a child split
313323
* occurred or because we needed to adjust our key for an insert in a
314324
* child node. Therefore, remove the old version of this node's key.
325+
*
326+
* Note: for WAL replay, in the non-split case we handle this by
327+
* setting up a one-element todelete array; in the split case, it's
328+
* handled implicitly because the tuple vector passed to gistSplit
329+
* won't include this tuple.
315330
*/
316331

317332
PageIndexTupleDelete(state->stack->page,state->stack->childoffnum);
@@ -336,9 +351,7 @@ gistplacetopage(GISTInsertState *state, GISTSTATE *giststate)
336351
XLogRecData*rdata;
337352

338353
rdata=formSplitRdata(state->r->rd_node,state->stack->blkno,
339-
&(state->key),dist);
340-
341-
START_CRIT_SECTION();
354+
is_leaf,&(state->key),dist);
342355

343356
recptr=XLogInsert(RM_GIST_ID,XLOG_GIST_PAGE_SPLIT,rdata);
344357
ptr=dist;
@@ -348,8 +361,6 @@ gistplacetopage(GISTInsertState *state, GISTSTATE *giststate)
348361
PageSetTLI(BufferGetPage(ptr->buffer),ThisTimeLineID);
349362
ptr=ptr->next;
350363
}
351-
352-
END_CRIT_SECTION();
353364
}
354365
else
355366
{
@@ -410,7 +421,6 @@ gistplacetopage(GISTInsertState *state, GISTSTATE *giststate)
410421
else
411422
ourpage=dist;
412423

413-
414424
/* now gets all needed data, and sets nsn's */
415425
page= (Page)BufferGetPage(ourpage->buffer);
416426
opaque=GistPageGetOpaque(page);
@@ -437,8 +447,11 @@ gistplacetopage(GISTInsertState *state, GISTSTATE *giststate)
437447
WriteBuffer(ptr->buffer);
438448
ptr=ptr->next;
439449
}
450+
451+
WriteNoReleaseBuffer(state->stack->buffer);
440452
}
441-
WriteNoReleaseBuffer(state->stack->buffer);
453+
454+
END_CRIT_SECTION();
442455
}
443456
else
444457
{
@@ -451,7 +464,7 @@ gistplacetopage(GISTInsertState *state, GISTSTATE *giststate)
451464
if (!state->r->rd_istemp)
452465
{
453466
OffsetNumbernoffs=0,
454-
offs[MAXALIGN(sizeof(OffsetNumber)) /sizeof(OffsetNumber)];
467+
offs[1];
455468
XLogRecPtrrecptr;
456469
XLogRecData*rdata;
457470

@@ -462,17 +475,14 @@ gistplacetopage(GISTInsertState *state, GISTSTATE *giststate)
462475
noffs=1;
463476
}
464477

465-
rdata=formUpdateRdata(state->r->rd_node,state->stack->blkno,
466-
offs,noffs, false,state->itup,state->ituplen,
478+
rdata=formUpdateRdata(state->r->rd_node,state->stack->buffer,
479+
offs,noffs, false,
480+
state->itup,state->ituplen,
467481
&(state->key));
468482

469-
START_CRIT_SECTION();
470-
471-
recptr=XLogInsert(RM_GIST_ID,XLOG_GIST_ENTRY_UPDATE,rdata);
483+
recptr=XLogInsert(RM_GIST_ID,XLOG_GIST_PAGE_UPDATE,rdata);
472484
PageSetLSN(state->stack->page,recptr);
473485
PageSetTLI(state->stack->page,ThisTimeLineID);
474-
475-
END_CRIT_SECTION();
476486
}
477487
else
478488
PageSetLSN(state->stack->page,XLogRecPtrForTemp);
@@ -481,6 +491,8 @@ gistplacetopage(GISTInsertState *state, GISTSTATE *giststate)
481491
state->needInsertComplete= false;
482492
WriteNoReleaseBuffer(state->stack->buffer);
483493

494+
END_CRIT_SECTION();
495+
484496
if (!is_leaf)/* small optimization: inform scan ablout
485497
* deleting... */
486498
gistadjscans(state->r,GISTOP_DEL,state->stack->blkno,
@@ -636,30 +648,14 @@ gistfindleaf(GISTInsertState *state, GISTSTATE *giststate)
636648
}
637649

638650
/*
639-
* Should have the same interface as XLogReadBuffer
640-
*/
641-
staticBuffer
642-
gistReadAndLockBuffer(Relationr,BlockNumberblkno)
643-
{
644-
Bufferbuffer=ReadBuffer(r,blkno);
645-
646-
LockBuffer(buffer,GIST_SHARE);
647-
returnbuffer;
648-
}
649-
650-
/*
651-
* Traverse the tree to find path from root page.
651+
* Traverse the tree to find path from root page to specified "child" block.
652652
*
653653
* returns from the begining of closest parent;
654654
*
655-
* Function is used in both regular and recovery mode, so must work with
656-
* different read functions (gistReadAndLockBuffer and XLogReadBuffer)
657-
*
658655
* To prevent deadlocks, this should lock only one page simultaneously.
659656
*/
660657
GISTInsertStack*
661-
gistFindPath(Relationr,BlockNumberchild,
662-
Buffer (*myReadBuffer) (Relation,BlockNumber))
658+
gistFindPath(Relationr,BlockNumberchild)
663659
{
664660
Pagepage;
665661
Bufferbuffer;
@@ -677,7 +673,8 @@ gistFindPath(Relation r, BlockNumber child,
677673

678674
while (top&&top->blkno!=child)
679675
{
680-
buffer=myReadBuffer(r,top->blkno);/* locks buffer */
676+
buffer=ReadBuffer(r,top->blkno);
677+
LockBuffer(buffer,GIST_SHARE);
681678
gistcheckpage(r,buffer);
682679
page= (Page)BufferGetPage(buffer);
683680

@@ -833,7 +830,7 @@ gistFindCorrectParent(Relation r, GISTInsertStack *child)
833830
}
834831

835832
/* ok, find new path */
836-
ptr=parent=gistFindPath(r,child->blkno,gistReadAndLockBuffer);
833+
ptr=parent=gistFindPath(r,child->blkno);
837834
Assert(ptr!=NULL);
838835

839836
/* read all buffers as expected by caller */
@@ -1192,27 +1189,31 @@ gistnewroot(Relation r, Buffer buffer, IndexTuple *itup, int len, ItemPointer ke
11921189

11931190
Assert(BufferGetBlockNumber(buffer)==GIST_ROOT_BLKNO);
11941191
page=BufferGetPage(buffer);
1195-
GISTInitBuffer(buffer,0);
11961192

1193+
START_CRIT_SECTION();
1194+
1195+
GISTInitBuffer(buffer,0);/* XXX not F_LEAF? */
11971196
gistfillbuffer(r,page,itup,len,FirstOffsetNumber);
1197+
11981198
if (!r->rd_istemp)
11991199
{
12001200
XLogRecPtrrecptr;
12011201
XLogRecData*rdata;
12021202

1203-
rdata=formUpdateRdata(r->rd_node,GIST_ROOT_BLKNO,
1204-
NULL,0, false,itup,len,key);
1205-
1206-
START_CRIT_SECTION();
1203+
rdata=formUpdateRdata(r->rd_node,buffer,
1204+
NULL,0, false,
1205+
itup,len,key);
12071206

12081207
recptr=XLogInsert(RM_GIST_ID,XLOG_GIST_NEW_ROOT,rdata);
12091208
PageSetLSN(page,recptr);
12101209
PageSetTLI(page,ThisTimeLineID);
1211-
1212-
END_CRIT_SECTION();
12131210
}
12141211
else
12151212
PageSetLSN(page,XLogRecPtrForTemp);
1213+
1214+
WriteNoReleaseBuffer(buffer);
1215+
1216+
END_CRIT_SECTION();
12161217
}
12171218

12181219
void

‎src/backend/access/gist/gistvacuum.c‎

Lines changed: 34 additions & 19 deletions
Original file line numberDiff line numberDiff line change
@@ -8,7 +8,7 @@
88
* Portions Copyright (c) 1994, Regents of the University of California
99
*
1010
* IDENTIFICATION
11-
* $PostgreSQL: pgsql/src/backend/access/gist/gistvacuum.c,v 1.16 2006/03/05 15:58:20 momjian Exp $
11+
* $PostgreSQL: pgsql/src/backend/access/gist/gistvacuum.c,v 1.17 2006/03/30 23:03:10 tgl Exp $
1212
*
1313
*-------------------------------------------------------------------------
1414
*/
@@ -80,6 +80,12 @@ gistVacuumUpdate(GistVacuum *gv, BlockNumber blkno, bool needunion)
8080
page= (Page)BufferGetPage(buffer);
8181
maxoff=PageGetMaxOffsetNumber(page);
8282

83+
/*
84+
* XXX need to reduce scope of changes to page so we can make this
85+
* critical section less extensive
86+
*/
87+
START_CRIT_SECTION();
88+
8389
if (GistPageIsLeaf(page))
8490
{
8591
if (GistTuplesDeleted(page))
@@ -188,11 +194,9 @@ gistVacuumUpdate(GistVacuum *gv, BlockNumber blkno, bool needunion)
188194
ItemPointerSet(&key,blkno,TUPLE_IS_VALID);
189195

190196
rdata=formSplitRdata(gv->index->rd_node,blkno,
191-
&key,dist);
197+
false,&key,dist);
192198
xlinfo=rdata->data;
193199

194-
START_CRIT_SECTION();
195-
196200
recptr=XLogInsert(RM_GIST_ID,XLOG_GIST_PAGE_SPLIT,rdata);
197201
ptr=dist;
198202
while (ptr)
@@ -202,7 +206,6 @@ gistVacuumUpdate(GistVacuum *gv, BlockNumber blkno, bool needunion)
202206
ptr=ptr->next;
203207
}
204208

205-
END_CRIT_SECTION();
206209
pfree(xlinfo);
207210
pfree(rdata);
208211
}
@@ -235,8 +238,6 @@ gistVacuumUpdate(GistVacuum *gv, BlockNumber blkno, bool needunion)
235238
oldCtx=MemoryContextSwitchTo(gv->opCtx);
236239
gistnewroot(gv->index,buffer,res.itup,res.ituplen,&key);
237240
MemoryContextSwitchTo(oldCtx);
238-
239-
WriteNoReleaseBuffer(buffer);
240241
}
241242

242243
needwrite= false;
@@ -302,15 +303,14 @@ gistVacuumUpdate(GistVacuum *gv, BlockNumber blkno, bool needunion)
302303
XLogRecPtrrecptr;
303304
char*xlinfo;
304305

305-
rdata=formUpdateRdata(gv->index->rd_node,blkno,todelete,ntodelete,
306-
res.emptypage,addon,curlenaddon,NULL);
306+
rdata=formUpdateRdata(gv->index->rd_node,buffer,
307+
todelete,ntodelete,res.emptypage,
308+
addon,curlenaddon,NULL);
307309
xlinfo=rdata->data;
308310

309-
START_CRIT_SECTION();
310-
recptr=XLogInsert(RM_GIST_ID,XLOG_GIST_ENTRY_UPDATE,rdata);
311+
recptr=XLogInsert(RM_GIST_ID,XLOG_GIST_PAGE_UPDATE,rdata);
311312
PageSetLSN(page,recptr);
312313
PageSetTLI(page,ThisTimeLineID);
313-
END_CRIT_SECTION();
314314

315315
pfree(xlinfo);
316316
pfree(rdata);
@@ -322,6 +322,8 @@ gistVacuumUpdate(GistVacuum *gv, BlockNumber blkno, bool needunion)
322322
else
323323
ReleaseBuffer(buffer);
324324

325+
END_CRIT_SECTION();
326+
325327
if (ncompleted&& !gv->index->rd_istemp)
326328
gistxlogInsertCompletion(gv->index->rd_node,completed,ncompleted);
327329

@@ -579,6 +581,17 @@ gistbulkdelete(PG_FUNCTION_ARGS)
579581
*/
580582
pushStackIfSplited(page,stack);
581583

584+
/*
585+
* Remove deletable tuples from page
586+
*
587+
* XXX try to make this critical section shorter. Could do it
588+
* by separating the callback loop from the actual tuple deletion,
589+
* but that would affect the definition of the todelete[] array
590+
* passed into the WAL record (because the indexes would all be
591+
* pre-deletion).
592+
*/
593+
START_CRIT_SECTION();
594+
582595
maxoff=PageGetMaxOffsetNumber(page);
583596

584597
for (i=FirstOffsetNumber;i <=maxoff;i=OffsetNumberNext(i))
@@ -608,17 +621,17 @@ gistbulkdelete(PG_FUNCTION_ARGS)
608621
{
609622
XLogRecData*rdata;
610623
XLogRecPtrrecptr;
611-
gistxlogEntryUpdate*xlinfo;
624+
gistxlogPageUpdate*xlinfo;
612625

613-
rdata=formUpdateRdata(rel->rd_node,stack->blkno,todelete,ntodelete,
614-
false,NULL,0,NULL);
615-
xlinfo= (gistxlogEntryUpdate*)rdata->data;
626+
rdata=formUpdateRdata(rel->rd_node,buffer,
627+
todelete,ntodelete, false,
628+
NULL,0,
629+
NULL);
630+
xlinfo= (gistxlogPageUpdate*)rdata->data;
616631

617-
START_CRIT_SECTION();
618-
recptr=XLogInsert(RM_GIST_ID,XLOG_GIST_ENTRY_UPDATE,rdata);
632+
recptr=XLogInsert(RM_GIST_ID,XLOG_GIST_PAGE_UPDATE,rdata);
619633
PageSetLSN(page,recptr);
620634
PageSetTLI(page,ThisTimeLineID);
621-
END_CRIT_SECTION();
622635

623636
pfree(xlinfo);
624637
pfree(rdata);
@@ -627,6 +640,8 @@ gistbulkdelete(PG_FUNCTION_ARGS)
627640
PageSetLSN(page,XLogRecPtrForTemp);
628641
WriteNoReleaseBuffer(buffer);
629642
}
643+
644+
END_CRIT_SECTION();
630645
}
631646
else
632647
{

0 commit comments

Comments
 (0)
[8]ページ先頭
©2009-2025 Movatter.jp