Change the definition of SQLITE_CONFIG_SCRATCH so that at most one scratch

buffer is used per thread.  Use the generic heap memory allocator for the
WalIterator object when running a checkpoint.

FossilOrigin-Name: 391c9b85abcb5ba300fb2e116384639310c69ed2

diff --git a/manifest b/manifest
index c02ddb43b9882ee7e1e63a0bd9cd86274b79ea9e..9decec2f003dcf3577dc002a61a9f2aa6b82c731 100644 (file)
--- a/manifest
+++ b/manifest
@@ -1,5 +1,5 @@
-C Improved\sdocumentation\sand\saddition\sof\ssource-code\sevidence\smarks\sfor\sthe\nsqlite3_config()\sinterface.
-D 2014-11-04T13:41:32.444
+C Change\sthe\sdefinition\sof\sSQLITE_CONFIG_SCRATCH\sso\sthat\sat\smost\sone\sscratch\nbuffer\sis\sused\sper\sthread.\s\sUse\sthe\sgeneric\sheap\smemory\sallocator\sfor\sthe\nWalIterator\sobject\swhen\srunning\sa\scheckpoint.
+D 2014-11-04T14:22:27.705
 F Makefile.arm-wince-mingw32ce-gcc d6df77f1f48d690bd73162294bbba7f59507c72f
 F Makefile.in cf57f673d77606ab0f2d9627ca52a9ba1464146a
 F Makefile.linux-gcc 91d710bdc4998cb015f39edf3cb314ec4f4d7e23
@@ -172,7 +172,7 @@ F src/auth.c b56c78ebe40a2110fd361379f7e8162d23f92240
 F src/backup.c 7f841396adfd47507ff670a471162d2bfcda3136
 F src/bitvec.c 19a4ba637bd85f8f63fc8c9bae5ade9fb05ec1cb
 F src/btmutex.c 49ca66250c7dfa844a4d4cb8272b87420d27d3a5
-F src/btree.c 5b6e02a2cb69bfba5d44d0a093b8cc7468fdcf61
+F src/btree.c 11d1262110c2d459b68121833fa3ec6625b1d022
 F src/btree.h 49b408be9c1cd41249076898e0673711071205d8
 F src/btreeInt.h 026d0129724e8f265fdc60d44ec240cf5a4e6179
 F src/build.c 67bb05b1077e0cdaccb2e36bfcbe7a5df9ed31e8
@@ -195,7 +195,7 @@ F src/legacy.c ba1863ea58c4c840335a84ec276fc2b25e22bc4e
 F src/lempar.c 7274c97d24bb46631e504332ccd3bd1b37841770
 F src/loadext.c de741e66e5ddc1598d904d7289239696e40ed994
 F src/main.c c673d0972da4b6826a3e907029faf5be0840cd57
-F src/malloc.c 3c3ac67969612493d435e14b6832793209afd2ec
+F src/malloc.c 740db54387204c9a2eb67c6d98e68b08e9ef4eab
 F src/mem0.c 6a55ebe57c46ca1a7d98da93aaa07f99f1059645
 F src/mem1.c faf615aafd8be74a71494dfa027c113ea5c6615f
 F src/mem2.c f1940d9e91948dd6a908fbb9ce3835c36b5d83c3
@@ -229,7 +229,7 @@ F src/resolve.c 4965007d6497b6a4d7a6d98751cc39712885f952
 F src/rowset.c eccf6af6d620aaa4579bd3b72c1b6395d9e9fa1e
 F src/select.c 428165951748151e87a15295b7357221433e311b
 F src/shell.c 282f8f5278e0c78eb442217531172ec9e1538796
-F src/sqlite.h.in 81c5105a19bd1c16a06d59e729ddc3bb0c26d003
+F src/sqlite.h.in 6e9af739d79f0bea2584b70fb1c54d3bb1a2eab6
 F src/sqlite3.rc 992c9f5fb8285ae285d6be28240a7e8d3a7f2bad
 F src/sqlite3ext.h 17d487c3c91b0b8c584a32fbeb393f6f795eea7d
 F src/sqliteInt.h 8f67ca79e957b8ece7453b8e320b6a996e1b4761
@@ -299,7 +299,7 @@ F src/vdbemem.c 31d8eabb0cd78bfeab4e5124c7363c3e9e54db9f
 F src/vdbesort.c daf87ea542df088ac4607660d09976d36b6bd95d
 F src/vdbetrace.c 7e4222955e07dd707a2f360c0eb73452be1cb010
 F src/vtab.c 2a30791bbd7926b589401bd09c3abb33de563793
-F src/wal.c 10e7de7ce90865a68153f001a61f1d985cd17983
+F src/wal.c 825c948066c7604a07d56e67958cdab210749016
 F src/wal.h df01efe09c5cb8c8e391ff1715cca294f89668a4
 F src/walker.c c253b95b4ee44b21c406e2a1052636c31ea27804
 F src/where.c d5fa1081bf7cb70478ed06489e063695c92ee1e1
@@ -1211,7 +1211,7 @@ F tool/vdbe_profile.tcl 67746953071a9f8f2f668b73fe899074e2c6d8c1
 F tool/warnings-clang.sh f6aa929dc20ef1f856af04a730772f59283631d4
 F tool/warnings.sh 0abfd78ceb09b7f7c27c688c8e3fe93268a13b32
 F tool/win/sqlite.vsix deb315d026cc8400325c5863eef847784a219a2f
-P 6eb03e62a34e8e0964175283587247b0212db604
-R a92bedb66491253840f18dd40e991665
+P 681031a436fdd4cce426d6cd43cbae6b83167d26
+R cb98a95faa41015902ec00cd7a294542
 U drh
-Z 6591907c91e192439bb8b0655576863e
+Z 113a55cc7642fbc8d6bb5b88b140b929

diff --git a/manifest.uuid b/manifest.uuid
index e57823b45ee5cfb688513cf9e8d01d264be9df8a..cd70e30b51b612bacc044e650741b8c379b5f159 100644 (file)
--- a/manifest.uuid
+++ b/manifest.uuid
@@ -1 +1 @@
-681031a436fdd4cce426d6cd43cbae6b83167d26
\ No newline at end of file
+391c9b85abcb5ba300fb2e116384639310c69ed2
\ No newline at end of file

diff --git a/src/btree.c b/src/btree.c
index 6fe8e10f3dff7bf53b692ab582cc14ba62f46020..fe15c922ca7032ab8290712f383b0d58a7c89f25 100644 (file)
--- a/src/btree.c
+++ b/src/btree.c
@@ -6650,12 +6650,9 @@ static int balance_nonroot(
      + nMaxCells*sizeof(u16)                       /* szCell */
      + pBt->pageSize;                              /* aSpace1 */
 
-  /* EVIDENCE-OF: R-37926-08392 SQLite will never request a scratch buffer
-  ** that is more than 6 times the database page size, except when
-  ** performing a checkpoint in WAL mode when the scratch buffer request
-  ** size is a small fraction of the size of the WAL file. */
+  /* EVIDENCE-OF: R-28375-38319 SQLite will never request a scratch buffer
+  ** that is more than 6 times the database page size. */
   assert( szScratch<=6*pBt->pageSize );
-
   apCell = sqlite3ScratchMalloc( szScratch ); 
   if( apCell==0 ){
     rc = SQLITE_NOMEM;

diff --git a/src/malloc.c b/src/malloc.c
index 6fb9d53d1b6c054ca04af84a9d440c0100650aeb..4960f91e02150e2f60f7dc1c86c05886153c8fef 100644 (file)
--- a/src/malloc.c
+++ b/src/malloc.c
@@ -377,11 +377,12 @@ void *sqlite3ScratchMalloc(int n){
 
 
 #if SQLITE_THREADSAFE==0 && !defined(NDEBUG)
-  /* Verify that no more than two scratch allocations per thread
-  ** are outstanding at one time.  (This is only checked in the
-  ** single-threaded case since checking in the multi-threaded case
-  ** would be much more complicated.) */
-  assert( scratchAllocOut<=1 );
+  /* EVIDENCE-OF: R-12970-05880 SQLite will not use more than one scratch
+  ** buffers per thread.
+  **
+  ** This can only be checked in single-threaded mode.
+  */
+  assert( scratchAllocOut==0 );
   if( p ) scratchAllocOut++;
 #endif
 

diff --git a/src/sqlite.h.in b/src/sqlite.h.in
index 271b7a0ad1290fd1d6c704cec3d17e885ed8fea5..44f7800ca22655647e1d8e7056a3192daab2df8d 100644 (file)
--- a/src/sqlite.h.in
+++ b/src/sqlite.h.in
@@ -1541,13 +1541,9 @@ struct sqlite3_mem_methods {
 ** and the maximum number of scratch allocations (N).)^
 ** The first argument must be a pointer to an 8-byte aligned buffer
 ** of at least sz*N bytes of memory.
-** ^SQLite will not use more than two scratch buffers per thread and not
-** more than one scratch buffer per thread when not performing
-** a [checkpoint] in [WAL mode].
+** ^SQLite will not use more than one scratch buffers per thread.
 ** ^SQLite will never request a scratch buffer that is more than 6
-** times the database page size, except when performing a [checkpoint]
-** in [WAL mode] when the scratch buffer request size is a small fraction
-** of the size of the WAL file.
+** times the database page size.
 ** ^If SQLite needs needs additional
 ** scratch memory beyond what is provided by this configuration option, then 
 ** [sqlite3_malloc()] will be used to obtain the memory needed.<p>

diff --git a/src/wal.c b/src/wal.c
index c0861d5be77552d55eb7988b650d20012da2493c..d2ed293a4dd032c1a2f8d254262b072071426e1b 100644 (file)
--- a/src/wal.c
+++ b/src/wal.c
@@ -1504,7 +1504,7 @@ static void walMergesort(
 ** Free an iterator allocated by walIteratorInit().
 */
 static void walIteratorFree(WalIterator *p){
-  sqlite3ScratchFree(p);
+  sqlite3_free(p);
 }
 
 /*
@@ -1539,7 +1539,7 @@ static int walIteratorInit(Wal *pWal, WalIterator **pp){
   nByte = sizeof(WalIterator) 
         + (nSegment-1)*sizeof(struct WalSegment)
         + iLast*sizeof(ht_slot);
-  p = (WalIterator *)sqlite3ScratchMalloc(nByte);
+  p = (WalIterator *)sqlite3_malloc(nByte);
   if( !p ){
     return SQLITE_NOMEM;
   }
@@ -1549,7 +1549,7 @@ static int walIteratorInit(Wal *pWal, WalIterator **pp){
   /* Allocate temporary space used by the merge-sort routine. This block
   ** of memory will be freed before this function returns.
   */
-  aTmp = (ht_slot *)sqlite3ScratchMalloc(
+  aTmp = (ht_slot *)sqlite3_malloc(
       sizeof(ht_slot) * (iLast>HASHTABLE_NPAGE?HASHTABLE_NPAGE:iLast)
   );
   if( !aTmp ){
@@ -1586,7 +1586,7 @@ static int walIteratorInit(Wal *pWal, WalIterator **pp){
       p->aSegment[i].aPgno = (u32 *)aPgno;
     }
   }
-  sqlite3ScratchFree(aTmp);
+  sqlite3_free(aTmp);
 
   if( rc!=SQLITE_OK ){
     walIteratorFree(p);