Performance enhancement for sqlite3DbFree().

FossilOrigin-Name: c296a9d958ec360fc8d217363348b4918d665bccb3c4f27503a2dcef7db49052

manifest

@@ -1,5 +1,5 @@
-C Add\sthe\snew\sinternal\sinterface\ssqlite3DbNNFreeNN(db,ptr)\swhere\sboth\sthe\ndb\sand\sptr\sparameters\sare\sguaranteed\sto\sbe\snon-NULL.\s\sUse\sthis\swhere\nappropriate\sto\ssave\smore\sthan\s2\smillion\sCPU\scycles\son\sthe\sstandard\nperformance\stest.
+C Performance\senhancement\sfor\ssqlite3DbFree().
-D 2022-08-22T02:00:26.214
+D 2022-08-22T15:18:37.415
 F .fossil-settings/empty-dirs dbb81e8fc0401ac46a1491ab34a7f2c7c0452f2f06b54ebb845d024ca8283ef1
 F .fossil-settings/ignore-glob 35175cdfcf539b2318cb04a9901442804be81cd677d8b889fcc9149c21f239ea
 F LICENSE.md df5091916dbb40e6e9686186587125e1b2ff51f022cc334e886c19a0e9982724
@@ -552,8 +552,8 @@ F src/insert.c aea5361767817f917b0f0f647a1f0b1621bd858938ae6ae545c3b6b9814b798f
 F src/json.c 7749b98c62f691697c7ee536b570c744c0583cab4a89200fdd0fc2aa8cc8cbd6
 F src/legacy.c d7874bc885906868cd51e6c2156698f2754f02d9eee1bae2d687323c3ca8e5aa
 F src/loadext.c 853385cc7a604157e137585097949252d5d0c731768e16b044608e5c95c3614b
-F src/main.c b91c7e71af6f33640c35b8239a285040aad8dfcfdaaf979152e743c0f8017ea8
+F src/main.c 211f5fd4110b0565fc2135d60ed12b4ef8a29d634414f471b5f957aa7b7f2afa
-F src/malloc.c 24369414a0fa402451cec0f0d1e94b637ce8e93c93cd29038ffe7629a8780ebf
+F src/malloc.c b7a3430cbe91d3e8e04fc10c2041b3a19794e63556ad2441a13d8dadd9b2bafc
 F src/mem0.c 6a55ebe57c46ca1a7d98da93aaa07f99f1059645
 F src/mem1.c c12a42539b1ba105e3707d0e628ad70e611040d8f5e38cf942cee30c867083de
 F src/mem2.c c8bfc9446fd0798bddd495eb5d9dbafa7d4b7287d8c22d50a83ac9daa26d8a75
@@ -593,9 +593,9 @@ F src/shell.c.in 269f682249c1bce2962883e5b99c8702b16a488a43b9ae186daa178713a93c5
 F src/sqlite.h.in b9b7fd73239d94db20332bb6e504688001e5564b655e1318a4427a1caef4b99e
 F src/sqlite3.rc 5121c9e10c3964d5755191c80dd1180c122fc3a8
 F src/sqlite3ext.h a988810c9b21c0dc36dc7a62735012339dc76fc7ab448fb0792721d30eacb69d
-F src/sqliteInt.h 51ccf8da51d5263a21543631f0c3bdca06e9fbe8238a1b2c8d7ba4f4cd118aea
+F src/sqliteInt.h ebf18764e404a2cef39ae5bfc8dd4a83bf0d70be1c444a4fbd8539eb35ef6ffd
 F src/sqliteLimit.h d7323ffea5208c6af2734574bae933ca8ed2ab728083caa117c9738581a31657
-F src/status.c 4a3da6d77eeb3531cb0dbdf7047772a2a1b99f98c69e90ce009c75fe6328b2c0
+F src/status.c 1593e408e8e9ac956e8ecdf7db2728d8aa3e9da3405849f08c0f1f7ee7df86b5
 F src/table.c 0f141b58a16de7e2fbe81c308379e7279f4c6b50eb08efeec5892794a0ba30d1
 F src/tclsqlite.c 4e64ba300a5a26e0f1170e09032429faeb65e45e8f3d1a7833e8edb69fc2979e
 F src/test1.c 1356984e97bff07e4a8cc3863e892f05b3348678a74783bb6f350b76316736f1
@@ -663,7 +663,7 @@ F src/vacuum.c bb346170b0b54c6683bba4a5983aea40485597fdf605c87ec8bc2e199fe88cd8
 F src/vdbe.c 4e57ac969bb2252598024ee3ebcb0885cb7976f1606e2bd77975a506da93ed50
 F src/vdbe.h 64619af62603dc3c4f5ff6ff6d2c8f389abd667a29ce6007ed44bd22b3211cd0
 F src/vdbeInt.h 2cad0aeeb106371ed0e0946bab89f60627087068847afc2451c05056961c18da
-F src/vdbeapi.c 4cfbf7ec3ed60366a38655f3f10316c5a3d68f6d4d06e462f88679392611c756
+F src/vdbeapi.c 6af7b32ada7ef8facafa91f57aedabd91633f254b34e9c0901ab402d4238e553
 F src/vdbeaux.c cd9fc2fb24755366b2718f5e9e02103c39804bdc9e630620aaec08bb3093c46c
 F src/vdbeblob.c 5e61ce31aca17db8fb60395407457a8c1c7fb471dde405e0cd675974611dcfcd
 F src/vdbemem.c c3ce80af15e2ff5c2824a8db881681cbf511376f13613da020bac6d320c535b1
@@ -1999,8 +1999,8 @@ F vsixtest/vsixtest.tcl 6a9a6ab600c25a91a7acc6293828957a386a8a93
 F vsixtest/vsixtest.vcxproj.data 2ed517e100c66dc455b492e1a33350c1b20fbcdc
 F vsixtest/vsixtest.vcxproj.filters 37e51ffedcdb064aad6ff33b6148725226cd608e
 F vsixtest/vsixtest_TemporaryKey.pfx e5b1b036facdb453873e7084e1cae9102ccc67a0
-P 2d13ec086e96a5446462ce0f689c40c8196e740cd693f5967bfe9eb961f03463
+P e5eaa80e81fdf86f2875a912b880272b8d099b82b08e945a7988c5dd0fe9d6b5
-R bf88e8a14ba34da9f9b58cc1ee676092
+R 5d3ac911bfb51b81f7438edbe16f7f7d
 U drh
-Z 1f007ec3ec70bab2436c890728aeb636
+Z 2b49dc0de08069abebcad82ed9e5f9e0
 # Remove this line to create a well-formed Fossil manifest.

manifest.uuid

@@ -1 +1 @@
-e5eaa80e81fdf86f2875a912b880272b8d099b82b08e945a7988c5dd0fe9d6b5
+c296a9d958ec360fc8d217363348b4918d665bccb3c4f27503a2dcef7db49052

src/main.c

@@ -824,18 +824,19 @@ static int setupLookaside(sqlite3 *db, void *pBuf, int sz, int cnt){
     db->lookaside.bMalloced = pBuf==0 ?1:0;
     db->lookaside.nSlot = nBig+nSm;
   }else{
-    db->lookaside.pStart = db;
+    db->lookaside.pStart = 0;
 #ifndef SQLITE_OMIT_TWOSIZE_LOOKASIDE
     db->lookaside.pSmallInit = 0;
     db->lookaside.pSmallFree = 0;
-    db->lookaside.pMiddle = db;
+    db->lookaside.pMiddle = 0;
 #endif /* SQLITE_OMIT_TWOSIZE_LOOKASIDE */
-    db->lookaside.pEnd = db;
+    db->lookaside.pEnd = 0;
     db->lookaside.bDisable = 1;
     db->lookaside.sz = 0;
     db->lookaside.bMalloced = 0;
     db->lookaside.nSlot = 0;
   }
+  db->lookaside.pTrueEnd = db->lookaside.pEnd;
   assert( sqlite3LookasideUsed(db,0)==0 );
 #endif /* SQLITE_OMIT_LOOKASIDE */
   return SQLITE_OK;

src/malloc.c

@@ -317,7 +317,7 @@ void *sqlite3_malloc64(sqlite3_uint64 n){
 */
 #ifndef SQLITE_OMIT_LOOKASIDE
 static int isLookaside(sqlite3 *db, const void *p){
-  return SQLITE_WITHIN(p, db->lookaside.pStart, db->lookaside.pEnd);
+  return SQLITE_WITHIN(p, db->lookaside.pStart, db->lookaside.pTrueEnd);
 }
 #else
 #define isLookaside(A,B) 0
@@ -341,18 +341,16 @@ static int lookasideMallocSize(sqlite3 *db, const void *p){
 int sqlite3DbMallocSize(sqlite3 *db, const void *p){
   assert( p!=0 );
 #ifdef SQLITE_DEBUG
-  if( db==0 || !isLookaside(db,p) ){
+  if( db==0 ){
-    if( db==0 ){
+    assert( sqlite3MemdebugNoType(p, (u8)~MEMTYPE_HEAP) );
-      assert( sqlite3MemdebugNoType(p, (u8)~MEMTYPE_HEAP) );
+    assert( sqlite3MemdebugHasType(p, MEMTYPE_HEAP) );
-      assert( sqlite3MemdebugHasType(p, MEMTYPE_HEAP) );
+  }else if( !isLookaside(db,p) ){
-    }else{
+    assert( sqlite3MemdebugHasType(p, (MEMTYPE_LOOKASIDE|MEMTYPE_HEAP)) );
-      assert( sqlite3MemdebugHasType(p, (MEMTYPE_LOOKASIDE|MEMTYPE_HEAP)) );
+    assert( sqlite3MemdebugNoType(p, (u8)~(MEMTYPE_LOOKASIDE|MEMTYPE_HEAP)) );
-      assert( sqlite3MemdebugNoType(p, (u8)~(MEMTYPE_LOOKASIDE|MEMTYPE_HEAP)) );
-    }
   }
 #endif
   if( db ){
-    if( ((uptr)p)<(uptr)(db->lookaside.pEnd) ){
+    if( ((uptr)p)<(uptr)(db->lookaside.pTrueEnd) ){
 #ifndef SQLITE_OMIT_TWOSIZE_LOOKASIDE
       if( ((uptr)p)>=(uptr)(db->lookaside.pMiddle) ){
         assert( sqlite3_mutex_held(db->mutex) );
@@ -408,14 +406,11 @@ void sqlite3DbFreeNN(sqlite3 *db, void *p){
   assert( db==0 || sqlite3_mutex_held(db->mutex) );
   assert( p!=0 );
   if( db ){
-    if( db->pnBytesFreed ){
-      measureAllocationSize(db, p);
-      return;
-    }
     if( ((uptr)p)<(uptr)(db->lookaside.pEnd) ){
 #ifndef SQLITE_OMIT_TWOSIZE_LOOKASIDE
       if( ((uptr)p)>=(uptr)(db->lookaside.pMiddle) ){
         LookasideSlot *pBuf = (LookasideSlot*)p;
+        assert( db->pnBytesFreed==0 );
 #ifdef SQLITE_DEBUG
         memset(p, 0xaa, LOOKASIDE_SMALL);  /* Trash freed content */
 #endif
@@ -426,6 +421,7 @@ void sqlite3DbFreeNN(sqlite3 *db, void *p){
 #endif /* SQLITE_OMIT_TWOSIZE_LOOKASIDE */
       if( ((uptr)p)>=(uptr)(db->lookaside.pStart) ){
         LookasideSlot *pBuf = (LookasideSlot*)p;
+        assert( db->pnBytesFreed==0 );
 #ifdef SQLITE_DEBUG
         memset(p, 0xaa, db->lookaside.szTrue);  /* Trash freed content */
 #endif
@@ -434,6 +430,10 @@ void sqlite3DbFreeNN(sqlite3 *db, void *p){
         return;
       }
     }
+    if( db->pnBytesFreed ){
+      measureAllocationSize(db, p);
+      return;
+    }
   }
   assert( sqlite3MemdebugHasType(p, (MEMTYPE_LOOKASIDE|MEMTYPE_HEAP)) );
   assert( sqlite3MemdebugNoType(p, (u8)~(MEMTYPE_LOOKASIDE|MEMTYPE_HEAP)) );
@@ -445,14 +445,11 @@ void sqlite3DbNNFreeNN(sqlite3 *db, void *p){
   assert( db!=0 );
   assert( sqlite3_mutex_held(db->mutex) );
   assert( p!=0 );
-  if( db->pnBytesFreed ){
-    measureAllocationSize(db, p);
-    return;
-  }
   if( ((uptr)p)<(uptr)(db->lookaside.pEnd) ){
 #ifndef SQLITE_OMIT_TWOSIZE_LOOKASIDE
     if( ((uptr)p)>=(uptr)(db->lookaside.pMiddle) ){
       LookasideSlot *pBuf = (LookasideSlot*)p;
+      assert( db->pnBytesFreed==0 );
 #ifdef SQLITE_DEBUG
       memset(p, 0xaa, LOOKASIDE_SMALL);  /* Trash freed content */
 #endif
@@ -463,6 +460,7 @@ void sqlite3DbNNFreeNN(sqlite3 *db, void *p){
 #endif /* SQLITE_OMIT_TWOSIZE_LOOKASIDE */
     if( ((uptr)p)>=(uptr)(db->lookaside.pStart) ){
       LookasideSlot *pBuf = (LookasideSlot*)p;
+      assert( db->pnBytesFreed==0 );
 #ifdef SQLITE_DEBUG
       memset(p, 0xaa, db->lookaside.szTrue);  /* Trash freed content */
 #endif
@@ -471,6 +469,10 @@ void sqlite3DbNNFreeNN(sqlite3 *db, void *p){
       return;
     }
   }
+  if( db->pnBytesFreed ){
+    measureAllocationSize(db, p);
+    return;
+  }
   assert( sqlite3MemdebugHasType(p, (MEMTYPE_LOOKASIDE|MEMTYPE_HEAP)) );
   assert( sqlite3MemdebugNoType(p, (u8)~(MEMTYPE_LOOKASIDE|MEMTYPE_HEAP)) );
   sqlite3MemdebugSetType(p, MEMTYPE_HEAP);

src/sqliteInt.h

@@ -1438,6 +1438,7 @@ struct Lookaside {
 #endif /* SQLITE_OMIT_TWOSIZE_LOOKASIDE */
   void *pStart;           /* First byte of available memory space */
   void *pEnd;             /* First byte past end of available space */
+  void *pTrueEnd;         /* True value of pEnd, when db->pnBytesFreed!=0 */
 };
 struct LookasideSlot {
   LookasideSlot *pNext;    /* Next buffer in the list of free buffers */

src/status.c

@@ -291,6 +291,8 @@ int sqlite3_db_status(
 
       sqlite3BtreeEnterAll(db);
       db->pnBytesFreed = &nByte;
+      assert( db->lookaside.pEnd==db->lookaside.pTrueEnd );
+      db->lookaside.pEnd = db->lookaside.pStart;
       for(i=0; i<db->nDb; i++){
         Schema *pSchema = db->aDb[i].pSchema;
         if( ALWAYS(pSchema!=0) ){
@@ -316,6 +318,7 @@ int sqlite3_db_status(
         }
       }
       db->pnBytesFreed = 0;
+      db->lookaside.pEnd = db->lookaside.pTrueEnd;
       sqlite3BtreeLeaveAll(db);
 
       *pHighwater = 0;
@@ -333,9 +336,12 @@ int sqlite3_db_status(
       int nByte = 0;              /* Used to accumulate return value */
 
       db->pnBytesFreed = &nByte;
+      assert( db->lookaside.pEnd==db->lookaside.pTrueEnd );
+      db->lookaside.pEnd = db->lookaside.pStart;
       for(pVdbe=db->pVdbe; pVdbe; pVdbe=pVdbe->pNext){
         sqlite3VdbeDelete(pVdbe);
       }
+      db->lookaside.pEnd = db->lookaside.pTrueEnd;
       db->pnBytesFreed = 0;
 
       *pHighwater = 0;  /* IMP: R-64479-57858 */

src/vdbeapi.c

@@ -1836,8 +1836,11 @@ int sqlite3_stmt_status(sqlite3_stmt *pStmt, int op, int resetFlag){
     sqlite3_mutex_enter(db->mutex);
     v = 0;
     db->pnBytesFreed = (int*)&v;
+    assert( db->lookaside.pEnd==db->lookaside.pTrueEnd );
+    db->lookaside.pEnd = db->lookaside.pStart;
     sqlite3VdbeDelete(pVdbe);
     db->pnBytesFreed = 0;
+    db->lookaside.pEnd = db->lookaside.pTrueEnd;
     sqlite3_mutex_leave(db->mutex);
   }else{
     v = pVdbe->aCounter[op];