Implement the "lookaside" memory allocation cache. Use of this cache makes
the speed1.test script run about 15% faster. Added new interfaces to
control the cache. (CVS 5488)
FossilOrigin-Name: e48f9697e9fea339e150ddc32940760027dd07d9
diff --git a/src/sqliteInt.h b/src/sqliteInt.h
index 5672394..518fa76 100644
--- a/src/sqliteInt.h
+++ b/src/sqliteInt.h
@@ -11,7 +11,7 @@
*************************************************************************
** Internal interface definitions for SQLite.
**
-** @(#) $Id: sqliteInt.h,v 1.746 2008/07/25 15:39:04 drh Exp $
+** @(#) $Id: sqliteInt.h,v 1.747 2008/07/28 19:34:54 drh Exp $
*/
#ifndef _SQLITEINT_H_
#define _SQLITEINT_H_
@@ -431,6 +431,12 @@
#define ArraySize(X) (sizeof(X)/sizeof(X[0]))
/*
+** The following value as a destructor means to use sqlite3DbFree().
+** This is an internal extension to SQLITE_STATIC and SQLITE_TRANSIENT.
+*/
+#define SQLITE_DYNAMIC ((sqlite3_destructor_type)sqlite3DbFree)
+
+/*
** Forward references to structures
*/
typedef struct AggInfo AggInfo;
@@ -448,6 +454,8 @@
typedef struct Index Index;
typedef struct KeyClass KeyClass;
typedef struct KeyInfo KeyInfo;
+typedef struct Lookaside Lookaside;
+typedef struct LookasideSlot LookasideSlot;
typedef struct Module Module;
typedef struct NameContext NameContext;
typedef struct Parse Parse;
@@ -550,6 +558,32 @@
#define SQLITE_N_LIMIT (SQLITE_LIMIT_VARIABLE_NUMBER+1)
/*
+** Lookaside malloc is a set of fixed-size buffers that can be used
+** to satisify small transient memory allocation requests for objects
+** associated with a particular database connection. The use of
+** lookaside malloc provides a significant performance enhancement
+** (approx 10%) by avoiding numerous malloc/free requests while parsing
+** SQL statements.
+**
+** The Lookaside structure holds configuration information about the
+** lookaside malloc subsystem. Each available memory allocation in
+** the lookaside subsystem is stored on a linked list of LookasideSlot
+** objects.
+*/
+struct Lookaside {
+ u16 sz; /* Size of each buffer in bytes */
+ u8 bEnabled; /* True if use lookaside. False to ignore it */
+ int nOut; /* Number of buffers currently checked out */
+ int mxOut; /* Highwater mark for nOut */
+ LookasideSlot *pFree; /* List if available buffers */
+ void *pStart; /* First byte of available memory space */
+ void *pEnd; /* First byte past end of available space */
+};
+struct LookasideSlot {
+ LookasideSlot *pNext; /* Next buffer in the list of free buffers */
+};
+
+/*
** Each database is an instance of the following structure.
**
** The sqlite.lastRowid records the last insert rowid generated by an
@@ -628,6 +662,7 @@
int isInterrupted; /* True if sqlite3_interrupt has been called */
double notUsed1; /* Spacer */
} u1;
+ Lookaside lookaside; /* Lookaside malloc configuration */
#ifndef SQLITE_OMIT_AUTHORIZATION
int (*xAuth)(void*,int,const char*,const char*,const char*,const char*);
/* Access authorization function */
@@ -867,6 +902,7 @@
** of a SELECT statement.
*/
struct Table {
+ sqlite3 *db; /* Associated database connection. Might be NULL. */
char *zName; /* Name of the table */
int nCol; /* Number of columns in this table */
Column *aCol; /* Information about each column */
@@ -1744,10 +1780,11 @@
** do not necessarily know how big the string will be in the end.
*/
struct StrAccum {
- char *zBase; /* A base allocation. Not from malloc. */
- char *zText; /* The string collected so far */
- int nChar; /* Length of the string so far */
- int nAlloc; /* Amount of space allocated in zText */
+ sqlite3 *db; /* Optional database for lookaside. Can be NULL */
+ char *zBase; /* A base allocation. Not from malloc. */
+ char *zText; /* The string collected so far */
+ int nChar; /* Length of the string so far */
+ int nAlloc; /* Amount of space allocated in zText */
int mxAlloc; /* Maximum allowed string length */
u8 mallocFailed; /* Becomes true if any memory allocation fails */
u8 useMalloc; /* True if zText is enlargable using realloc */
@@ -1775,6 +1812,8 @@
int bCoreMutex; /* True to enable core mutexing */
int bFullMutex; /* True to enable full mutexing */
int mxStrlen; /* Maximum string length */
+ int szLookaside; /* Default lookaside buffer size */
+ int nLookaside; /* Default lookaside buffer count */
sqlite3_mem_methods m; /* Low-level memory allocation interface */
sqlite3_mutex_methods mutex; /* Low-level mutex interface */
void *pHeap; /* Heap storage space */
@@ -1830,14 +1869,14 @@
void *sqlite3MallocZero(int);
void *sqlite3DbMallocZero(sqlite3*, int);
void *sqlite3DbMallocRaw(sqlite3*, int);
-char *sqlite3StrDup(const char*);
-char *sqlite3StrNDup(const char*, int);
char *sqlite3DbStrDup(sqlite3*,const char*);
char *sqlite3DbStrNDup(sqlite3*,const char*, int);
void *sqlite3Realloc(void*, int);
void *sqlite3DbReallocOrFree(sqlite3 *, void *, int);
void *sqlite3DbRealloc(sqlite3 *, void *, int);
-int sqlite3MallocSize(void *);
+void sqlite3DbFree(sqlite3*, void*);
+int sqlite3MallocSize(void*);
+int sqlite3DbMallocSize(sqlite3*, void*);
void *sqlite3ScratchMalloc(int);
void sqlite3ScratchFree(void*);
void *sqlite3PageMalloc(int);
@@ -1866,6 +1905,7 @@
void sqlite3VXPrintf(StrAccum*, int, const char*, va_list);
char *sqlite3MPrintf(sqlite3*,const char*, ...);
char *sqlite3VMPrintf(sqlite3*,const char*, va_list);
+char *sqlite3MAppendf(sqlite3*,char*,const char*,...);
#if defined(SQLITE_TEST) || defined(SQLITE_DEBUG)
void sqlite3DebugPrintf(const char*, ...);
#endif
@@ -1891,9 +1931,9 @@
void sqlite3ExprSpan(Expr*,Token*,Token*);
Expr *sqlite3ExprFunction(Parse*,ExprList*, Token*);
void sqlite3ExprAssignVarNumber(Parse*, Expr*);
-void sqlite3ExprDelete(Expr*);
+void sqlite3ExprDelete(sqlite3*, Expr*);
ExprList *sqlite3ExprListAppend(Parse*,ExprList*,Expr*,Token*);
-void sqlite3ExprListDelete(ExprList*);
+void sqlite3ExprListDelete(sqlite3*, ExprList*);
int sqlite3Init(sqlite3*, char**);
int sqlite3InitCallback(void*, int, char**, char**);
void sqlite3Pragma(Parse*,Token*,Token*,Token*,int);
@@ -1938,15 +1978,15 @@
Select*, Expr*, IdList*);
void sqlite3SrcListShiftJoinType(SrcList*);
void sqlite3SrcListAssignCursors(Parse*, SrcList*);
-void sqlite3IdListDelete(IdList*);
-void sqlite3SrcListDelete(SrcList*);
+void sqlite3IdListDelete(sqlite3*, IdList*);
+void sqlite3SrcListDelete(sqlite3*, SrcList*);
void sqlite3CreateIndex(Parse*,Token*,Token*,SrcList*,ExprList*,int,Token*,
Token*, int, int);
void sqlite3DropIndex(Parse*, SrcList*, int);
int sqlite3Select(Parse*, Select*, SelectDest*, Select*, int, int*);
Select *sqlite3SelectNew(Parse*,ExprList*,SrcList*,Expr*,ExprList*,
Expr*,ExprList*,int,Expr*,Expr*);
-void sqlite3SelectDelete(Select*);
+void sqlite3SelectDelete(sqlite3*, Select*);
Table *sqlite3SrcListLookup(Parse*, SrcList*);
int sqlite3IsReadOnly(Parse*, Table*, int);
void sqlite3OpenTable(Parse*, int iCur, int iDb, Table*, int);
@@ -2035,17 +2075,17 @@
int sqlite3CodeRowTrigger(Parse*, int, ExprList*, int, Table *, int, int,
int, int, u32*, u32*);
void sqliteViewTriggers(Parse*, Table*, Expr*, int, ExprList*);
- void sqlite3DeleteTriggerStep(TriggerStep*);
+ void sqlite3DeleteTriggerStep(sqlite3*, TriggerStep*);
TriggerStep *sqlite3TriggerSelectStep(sqlite3*,Select*);
TriggerStep *sqlite3TriggerInsertStep(sqlite3*,Token*, IdList*,
ExprList*,Select*,int);
TriggerStep *sqlite3TriggerUpdateStep(sqlite3*,Token*,ExprList*, Expr*, int);
TriggerStep *sqlite3TriggerDeleteStep(sqlite3*,Token*, Expr*);
- void sqlite3DeleteTrigger(Trigger*);
+ void sqlite3DeleteTrigger(sqlite3*, Trigger*);
void sqlite3UnlinkAndDeleteTrigger(sqlite3*,int,const char*);
#else
# define sqlite3TriggersExist(A,B,C,D,E,F) 0
-# define sqlite3DeleteTrigger(A)
+# define sqlite3DeleteTrigger(A,B)
# define sqlite3DropTriggerPtr(A,B)
# define sqlite3UnlinkAndDeleteTrigger(A,B,C)
# define sqlite3CodeRowTrigger(A,B,C,D,E,F,G,H,I,J,K) 0