Ensure that all details of the ARC algorithm are hidden within freelist.c.

This refactoring does not change any algorithms or data structures, just
remove visibility of the ARC datastructures from other source files.

1 files changed, 15 insertions, 65 deletions

diff --git a/src/include/storage/buf_internals.h b/src/include/storage/buf_internals.h
index a89999f38f4..00b0b8af48a 100644
--- a/src/include/storage/buf_internals.h
+++ b/src/include/storage/buf_internals.h
@@ -8,7 +8,7 @@
  * Portions Copyright (c) 1996-2005, PostgreSQL Global Development Group
  * Portions Copyright (c) 1994, Regents of the University of California
  *
- * $PostgreSQL: pgsql/src/include/storage/buf_internals.h,v 1.75 2004/12/31 22:03:42 pgsql Exp $
+ * $PostgreSQL: pgsql/src/include/storage/buf_internals.h,v 1.75.4.1 2005/02/03 23:30:12 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -17,8 +17,9 @@
 
 #include "storage/backendid.h"
 #include "storage/buf.h"
-#include "storage/lmgr.h"
 #include "storage/lwlock.h"
+#include "storage/shmem.h"
+#include "utils/rel.h"
 
 
 /*
@@ -40,10 +41,10 @@ typedef bits16 BufFlags;
  * Buffer tag identifies which disk block the buffer contains.
  *
  * Note: the BufferTag data must be sufficient to determine where to write the
- * block, even during a "blind write" with no relcache entry.  It's possible
- * that the backend flushing the buffer doesn't even believe the relation is
- * visible yet (its xact may have started before the xact that created the
- * rel).  The storage manager must be able to cope anyway.
+ * block, without reference to pg_class or pg_tablespace entries.  It's
+ * possible that the backend flushing the buffer doesn't even believe the
+ * relation is visible yet (its xact may have started before the xact that
+ * created the rel).  The storage manager must be able to cope anyway.
  *
  * Note: if there's any pad bytes in the struct, INIT_BUFFERTAG will have
  * to be fixed to zero them, since this struct is used as a hash key.
@@ -107,58 +108,12 @@ typedef struct sbufdesc
 
 #define BufferDescriptorGetBuffer(bdesc) ((bdesc)->buf_id + 1)
 
-/* entry for buffer lookup hashtable */
-typedef struct
-{
-	BufferTag	key;			/* Tag of a disk page */
-	int			id;				/* CDB id of associated CDB */
-} BufferLookupEnt;
-
-/*
- * Definitions for the buffer replacement strategy
- */
-#define STRAT_LIST_UNUSED	(-1)
-#define STRAT_LIST_B1		0
-#define STRAT_LIST_T1		1
-#define STRAT_LIST_T2		2
-#define STRAT_LIST_B2		3
-#define STRAT_NUM_LISTS		4
-
-/*
- * The Cache Directory Block (CDB) of the Adaptive Replacement Cache (ARC)
- */
-typedef struct
-{
-	int			prev;			/* list links */
-	int			next;
-	short		list;			/* ID of list it is currently in */
-	bool		t1_vacuum;		/* t => present only because of VACUUM */
-	TransactionId t1_xid;		/* the xid this entry went onto T1 */
-	BufferTag	buf_tag;		/* page identifier */
-	int			buf_id;			/* currently assigned data buffer, or -1 */
-} BufferStrategyCDB;
-
-/*
- * The shared ARC control information.
- */
-typedef struct
-{
-	int			target_T1_size; /* What T1 size are we aiming for */
-	int			listUnusedCDB;	/* All unused StrategyCDB */
-	int			listHead[STRAT_NUM_LISTS];		/* ARC lists B1, T1, T2
-												 * and B2 */
-	int			listTail[STRAT_NUM_LISTS];
-	int			listSize[STRAT_NUM_LISTS];
-	Buffer		listFreeBuffers;	/* List of unused buffers */
-
-	long		num_lookup;		/* Some hit statistics */
-	long		num_hit[STRAT_NUM_LISTS];
-	time_t		stat_report;
 
-	/* Array of CDB's starts here */
-	BufferStrategyCDB cdb[1];	/* VARIABLE SIZE ARRAY */
-} BufferStrategyControl;
+/* in bufmgr.c */
+extern BufferDesc *BufferDescriptors;
 
+/* in localbuf.c */
+extern BufferDesc *LocalBufferDescriptors;
 
 /* counters in buf_init.c */
 extern long int ReadBufferCount;
@@ -170,11 +125,9 @@ extern long int LocalBufferFlushCount;
 
 
 /*
- * Bufmgr Interface:
+ * Internal routines: only called by bufmgr
  */
 
-/* Internal routines: only called by bufmgr */
-
 /* freelist.c */
 extern BufferDesc *StrategyBufferLookup(BufferTag *tagPtr, bool recheck,
 					 int *cdb_found_index);
@@ -185,20 +138,17 @@ extern void StrategyInvalidateBuffer(BufferDesc *buf);
 extern void StrategyHintVacuum(bool vacuum_active);
 extern int StrategyDirtyBufferList(BufferDesc **buffers, BufferTag *buftags,
 						int max_buffers);
+extern int	StrategyShmemSize(void);
 extern void StrategyInitialize(bool init);
 
 /* buf_table.c */
+extern int	BufTableShmemSize(int size);
 extern void InitBufTable(int size);
 extern int	BufTableLookup(BufferTag *tagPtr);
-extern void BufTableInsert(BufferTag *tagPtr, int cdb_id);
+extern void BufTableInsert(BufferTag *tagPtr, int buf_id);
 extern void BufTableDelete(BufferTag *tagPtr);
 
-/* bufmgr.c */
-extern BufferDesc *BufferDescriptors;
-
 /* localbuf.c */
-extern BufferDesc *LocalBufferDescriptors;
-
 extern BufferDesc *LocalBufferAlloc(Relation reln, BlockNumber blockNum,
 				 bool *foundPtr);
 extern void WriteLocalBuffer(Buffer buffer, bool release);