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Jan WieckJan Wieck
Jan Wieck
authored and
Jan Wieck
committed
ARC strategy backed out ... sorry
Jan
1 parent 256d2f0 commit 923e994

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9 files changed

+216
-932
lines changed

9 files changed

+216
-932
lines changed

‎src/backend/commands/vacuum.c

Lines changed: 1 addition & 21 deletions
Original file line numberDiff line numberDiff line change
@@ -13,7 +13,7 @@
1313
*
1414
*
1515
* IDENTIFICATION
16-
* $Header: /cvsroot/pgsql/src/backend/commands/vacuum.c,v 1.266 2003/11/13 00:40:00 wieck Exp $
16+
* $Header: /cvsroot/pgsql/src/backend/commands/vacuum.c,v 1.267 2003/11/13 05:34:57 wieck Exp $
1717
*
1818
*-------------------------------------------------------------------------
1919
*/
@@ -33,7 +33,6 @@
3333
#include "commands/vacuum.h"
3434
#include "executor/executor.h"
3535
#include "miscadmin.h"
36-
#include "storage/buf_internals.h"
3736
#include "storage/freespace.h"
3837
#include "storage/sinval.h"
3938
#include "storage/smgr.h"
@@ -311,16 +310,8 @@ vacuum(VacuumStmt *vacstmt)
311310
else
312311
old_context = MemoryContextSwitchTo(anl_context);
313312

314-
/*
315-
* Tell the buffer replacement strategy that vacuum is
316-
* causing the IO
317-
*/
318-
StrategyHintVacuum(true);
319-
320313
analyze_rel(relid, vacstmt);
321314

322-
StrategyHintVacuum(false);
323-
324315
if (vacstmt->vacuum)
325316
CommitTransactionCommand();
326317
else
@@ -758,12 +749,6 @@ vacuum_rel(Oid relid, VacuumStmt *vacstmt, char expected_relkind)
758749
SetQuerySnapshot(); /* might be needed for functions in
759750
* indexes */
760751

761-
/*
762-
* Tell the cache replacement strategy that vacuum is causing
763-
* all following IO
764-
*/
765-
StrategyHintVacuum(true);
766-
767752
/*
768753
* Check for user-requested abort. Note we want this to be inside a
769754
* transaction, so xact.c doesn't issue useless WARNING.
@@ -778,7 +763,6 @@ vacuum_rel(Oid relid, VacuumStmt *vacstmt, char expected_relkind)
778763
ObjectIdGetDatum(relid),
779764
0, 0, 0))
780765
{
781-
StrategyHintVacuum(false);
782766
CommitTransactionCommand();
783767
return true; /* okay 'cause no data there */
784768
}
@@ -812,7 +796,6 @@ vacuum_rel(Oid relid, VacuumStmt *vacstmt, char expected_relkind)
812796
(errmsg("skipping \"%s\" --- only table or database owner can vacuum it",
813797
RelationGetRelationName(onerel))));
814798
relation_close(onerel, lmode);
815-
StrategyHintVacuum(false);
816799
CommitTransactionCommand();
817800
return false;
818801
}
@@ -827,7 +810,6 @@ vacuum_rel(Oid relid, VacuumStmt *vacstmt, char expected_relkind)
827810
(errmsg("skipping \"%s\" --- cannot vacuum indexes, views, or special system tables",
828811
RelationGetRelationName(onerel))));
829812
relation_close(onerel, lmode);
830-
StrategyHintVacuum(false);
831813
CommitTransactionCommand();
832814
return false;
833815
}
@@ -842,7 +824,6 @@ vacuum_rel(Oid relid, VacuumStmt *vacstmt, char expected_relkind)
842824
if (isOtherTempNamespace(RelationGetNamespace(onerel)))
843825
{
844826
relation_close(onerel, lmode);
845-
StrategyHintVacuum(false);
846827
CommitTransactionCommand();
847828
return true; /* assume no long-lived data in temp
848829
* tables */
@@ -882,7 +863,6 @@ vacuum_rel(Oid relid, VacuumStmt *vacstmt, char expected_relkind)
882863
/*
883864
* Complete the transaction and free all temporary memory used.
884865
*/
885-
StrategyHintVacuum(false);
886866
CommitTransactionCommand();
887867

888868
/*

‎src/backend/storage/buffer/buf_init.c

Lines changed: 18 additions & 8 deletions
Original file line numberDiff line numberDiff line change
@@ -8,7 +8,7 @@
88
*
99
*
1010
* IDENTIFICATION
11-
* $Header: /cvsroot/pgsql/src/backend/storage/buffer/buf_init.c,v 1.55 2003/11/13 00:40:01 wieck Exp $
11+
* $Header: /cvsroot/pgsql/src/backend/storage/buffer/buf_init.c,v 1.56 2003/11/13 05:34:58 wieck Exp $
1212
*
1313
*-------------------------------------------------------------------------
1414
*/
@@ -48,6 +48,9 @@ long *CurTraceBuf;
4848
int ShowPinTrace = 0;
4949

5050
int Data_Descriptors;
51+
int Free_List_Descriptor;
52+
int Lookup_List_Descriptor;
53+
int Num_Descriptors;
5154

5255
BufferDesc *BufferDescriptors;
5356
Block *BufferBlockPointers;
@@ -130,6 +133,9 @@ InitBufferPool(void)
130133
int i;
131134

132135
Data_Descriptors = NBuffers;
136+
Free_List_Descriptor = Data_Descriptors;
137+
Lookup_List_Descriptor = Data_Descriptors + 1;
138+
Num_Descriptors = Data_Descriptors + 1;
133139

134140
/*
135141
* It's probably not really necessary to grab the lock --- if there's
@@ -150,7 +156,7 @@ InitBufferPool(void)
150156

151157
BufferDescriptors = (BufferDesc *)
152158
ShmemInitStruct("Buffer Descriptors",
153-
Data_Descriptors * sizeof(BufferDesc), &foundDescs);
159+
Num_Descriptors * sizeof(BufferDesc), &foundDescs);
154160

155161
BufferBlocks = (char *)
156162
ShmemInitStruct("Buffer Blocks",
@@ -170,14 +176,16 @@ InitBufferPool(void)
170176
block = BufferBlocks;
171177

172178
/*
173-
* link the buffers into a single linked list. This will become the
174-
* LiFo list of unused buffers returned by StragegyGetBuffer().
179+
* link the buffers into a circular, doubly-linked list to
180+
* initialize free list, and initialize the buffer headers. Still
181+
* don't know anything about replacement strategy in this file.
175182
*/
176183
for (i = 0; i < Data_Descriptors; block += BLCKSZ, buf++, i++)
177184
{
178185
Assert(ShmemIsValid((unsigned long) block));
179186

180-
buf->bufNext = i + 1;
187+
buf->freeNext = i + 1;
188+
buf->freePrev = i - 1;
181189

182190
CLEAR_BUFFERTAG(&(buf->tag));
183191
buf->buf_id = i;
@@ -191,12 +199,14 @@ InitBufferPool(void)
191199
buf->wait_backend_id = 0;
192200
}
193201

194-
/* Correct last entry */
195-
BufferDescriptors[Data_Descriptors - 1].bufNext = -1;
202+
/* close the circular queue */
203+
BufferDescriptors[0].freePrev = Data_Descriptors - 1;
204+
BufferDescriptors[Data_Descriptors - 1].freeNext = 0;
196205
}
197206

198207
/* Init other shared buffer-management stuff */
199-
StrategyInitialize(!foundDescs);
208+
InitBufTable();
209+
InitFreeList(!foundDescs);
200210

201211
LWLockRelease(BufMgrLock);
202212
}

‎src/backend/storage/buffer/buf_table.c

Lines changed: 42 additions & 26 deletions
Original file line numberDiff line numberDiff line change
@@ -8,7 +8,7 @@
88
*
99
*
1010
* IDENTIFICATION
11-
* $Header: /cvsroot/pgsql/src/backend/storage/buffer/buf_table.c,v 1.30 2003/11/13 00:40:01 wieck Exp $
11+
* $Header: /cvsroot/pgsql/src/backend/storage/buffer/buf_table.c,v 1.31 2003/11/13 05:34:58 wieck Exp $
1212
*
1313
*-------------------------------------------------------------------------
1414
*/
@@ -38,7 +38,7 @@ static HTAB *SharedBufHash;
3838
* Initialize shmem hash table for mapping buffers
3939
*/
4040
void
41-
InitBufTable(int size)
41+
InitBufTable(void)
4242
{
4343
HASHCTL info;
4444

@@ -50,71 +50,87 @@ InitBufTable(int size)
5050
info.hash = tag_hash;
5151

5252
SharedBufHash = ShmemInitHash("Shared Buffer Lookup Table",
53-
size, size,
53+
NBuffers, NBuffers,
5454
&info,
5555
HASH_ELEM | HASH_FUNCTION);
5656

5757
if (!SharedBufHash)
5858
elog(FATAL, "could not initialize shared buffer hash table");
5959
}
6060

61-
/*
62-
* BufTableLookup
63-
*/
64-
int
61+
BufferDesc *
6562
BufTableLookup(BufferTag *tagPtr)
6663
{
6764
BufferLookupEnt *result;
6865

6966
if (tagPtr->blockNum == P_NEW)
70-
return -1;
67+
return NULL;
7168

7269
result = (BufferLookupEnt *)
7370
hash_search(SharedBufHash, (void *) tagPtr, HASH_FIND, NULL);
7471
if (!result)
75-
return -1;
72+
return NULL;
7673

77-
return result->id;
74+
return &(BufferDescriptors[result->id]);
7875
}
7976

8077
/*
8178
* BufTableDelete
8279
*/
8380
bool
84-
BufTableInsert(BufferTag *tagPtr, Buffer buf_id)
81+
BufTableDelete(BufferDesc *buf)
8582
{
8683
BufferLookupEnt *result;
87-
bool found;
8884

89-
result = (BufferLookupEnt *)
90-
hash_search(SharedBufHash, (void *) tagPtr, HASH_ENTER, &found);
85+
/*
86+
* buffer not initialized or has been removed from table already.
87+
* BM_DELETED keeps us from removing buffer twice.
88+
*/
89+
if (buf->flags & BM_DELETED)
90+
return TRUE;
9191

92-
if (!result)
93-
ereport(ERROR,
94-
(errcode(ERRCODE_OUT_OF_MEMORY),
95-
errmsg("out of shared memory")));
92+
buf->flags |= BM_DELETED;
9693

97-
if (found) /* found something else in the table? */
94+
result = (BufferLookupEnt *)
95+
hash_search(SharedBufHash, (void *) &(buf->tag), HASH_REMOVE, NULL);
96+
97+
if (!result) /* shouldn't happen */
9898
elog(ERROR, "shared buffer hash table corrupted");
9999

100-
result->id = buf_id;
100+
/*
101+
* Clear the buffer's tag. This doesn't matter for the hash table,
102+
* since the buffer is already removed from it, but it ensures that
103+
* sequential searches through the buffer table won't think the buffer
104+
* is still valid for its old page.
105+
*/
106+
buf->tag.rnode.relNode = InvalidOid;
107+
buf->tag.rnode.tblNode = InvalidOid;
108+
101109
return TRUE;
102110
}
103111

104-
/*
105-
* BufTableDelete
106-
*/
107112
bool
108-
BufTableDelete(BufferTag *tagPtr)
113+
BufTableInsert(BufferDesc *buf)
109114
{
110115
BufferLookupEnt *result;
116+
bool found;
117+
118+
/* cannot insert it twice */
119+
Assert(buf->flags & BM_DELETED);
120+
buf->flags &= ~(BM_DELETED);
111121

112122
result = (BufferLookupEnt *)
113-
hash_search(SharedBufHash, (void *) tagPtr, HASH_REMOVE, NULL);
123+
hash_search(SharedBufHash, (void *) &(buf->tag), HASH_ENTER, &found);
114124

115-
if (!result) /* shouldn't happen */
125+
if (!result)
126+
ereport(ERROR,
127+
(errcode(ERRCODE_OUT_OF_MEMORY),
128+
errmsg("out of shared memory")));
129+
130+
if (found) /* found something else in the table? */
116131
elog(ERROR, "shared buffer hash table corrupted");
117132

133+
result->id = buf->buf_id;
118134
return TRUE;
119135
}
120136

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