Add a runtime interface to enable memory-management features. (CVS 2894)

FossilOrigin-Name: 44f8e3139aa3ad3fcce9028565dd9ad23bbe62a2

manifest

@@ -1,5 +1,5 @@
-C Rename\sDbSchema\sto\s"Schema"\sand\sSqliteTsd\sto\s"ThreadData".\s(CVS\s2893)
-D 2006-01-09T06:29:48
+C Add\sa\sruntime\sinterface\sto\senable\smemory-management\sfeatures.\s(CVS\s2894)
+D 2006-01-09T09:59:49
 F Makefile.in c79fbdaa264c6afcd435f2fb492551de5a8cf80d
 F Makefile.linux-gcc aee18d8a05546dcf1888bd4547e442008a49a092
 F README 9c4e2d6706bdcc3efdd773ce752a8cdab4f90028
@@ -34,7 +34,7 @@ F src/alter.c d0dd079b9ef0d551ff4a4ce09ee270c07b307bbb
 F src/analyze.c ed87abad3f6f60e1bd5308ed6ff6e0fa396db52b
 F src/attach.c 833e38b4fa6966de05fcf875c94cd521478a2811
 F src/auth.c cdec356a5cd8b217c346f816c5912221537fe87f
-F src/btree.c fc3f7f936b4f58c05ce95d710c1c15bb86cd522a
+F src/btree.c 5e5dff4a667d93d49925d38de2d451a5bd1eabfd
 F src/btree.h 5663c4f43e8521546ccebc8fc95acb013b8f3184
 F src/build.c e40a4caaba4afab3fc7f0866ca8766e8146dd62c
 F src/callback.c 79cfbac59139b525e3a195ee27b8be1ca06fbd38
@@ -59,7 +59,7 @@ F src/os_unix.c c5d1a3fe88ad93b5f6a29f1b5b889f2a756aaec0
 F src/os_unix.h 5768d56d28240d3fe4537fac08cc85e4fb52279e
 F src/os_win.c 9cedcb13d6bcd4ab5f50907a99112f45cd335893
 F src/os_win.h 41a946bea10f61c158ce8645e7646b29d44f122b
-F src/pager.c f838695a6c0c8d0051ce7491036fd675052aa6f6
+F src/pager.c 6fbcc25f1f3fbe62cbbda3af3dbb9c3d758f8050
 F src/pager.h e0acb095b3ad0bca48f2ab00c87346665643f64f
 F src/parse.y 83df51fea35f68f7e07384d75dce83d1ed30434c
 F src/pragma.c 7358baf8e2be14a0f3d71e7afae41e430d76b054
@@ -68,11 +68,11 @@ F src/printf.c f47a2f4b5387cd2ebb12e9117a1a5d6bd9a2b812
 F src/random.c d40f8d356cecbd351ccfab6eaedd7ec1b54f5261
 F src/select.c d97a43973d82a2e1e24be43ca5543c08b93e9e8d
 F src/shell.c 66b073375efbdee19045e7e0cd38b85f9aff71da
-F src/sqlite.h.in ba3a29daa6a16e054191ccb384a981964e882a1d
-F src/sqliteInt.h 9fed92df9ab1cccbe649c28e6d24685a1f3373a4
+F src/sqlite.h.in 537bac9e9ef703695268aaad5c56b6bf64f815be
+F src/sqliteInt.h f9e4b620da09737e678271d45135088027d80307
 F src/table.c 486dcfce532685b53b5a2b5da8bba0ded6fb2316
 F src/tclsqlite.c 42151e6c78502277be77b88c00535d53ce89b917
-F src/test1.c 25e687fcc3c962958c5aa5114a74592cc5b7e6ba
+F src/test1.c a526810f7d1c73b7b9a85621dd655d4357e0ae6d
 F src/test2.c ca74a1d8aeb7d9606e8f6b762c5daf85c1a3f92b
 F src/test3.c 9742aa146eb750cab81c1d5605286c3a0eb88054
 F src/test4.c a8fd681e139e1c61f22a77d07fc3a99cb28fff3f
@@ -82,7 +82,7 @@ F src/tokenize.c 196486012c871cdcad6cc84a820cc988603f1b9d
 F src/trigger.c c515afa5fe964e9854c54dc66dde179a90d0cfe3
 F src/update.c 9a3761250c2ac9e6871f4e9c37560b224ba0067e
 F src/utf.c b7bffac4260177ae7f83c01d025fe0f5ed70ce71
-F src/util.c 9af2eab4203627982e433102be55b58dd38f8a38
+F src/util.c 0153015d99468e994a2c9bc6746262654ed5914a
 F src/vacuum.c f5a068096b22fad438bf1f1cf69ccb7f9e8cc7fb
 F src/vdbe.c ce31105fc91e1ea346e2383cd536149cc66c34bd
 F src/vdbe.h 8729a4ee16ff9aeab2af9667df3cf300ff978e13
@@ -186,7 +186,7 @@ F test/malloc.test 6245418d1b6635a2095d9ed0f5e84e029990da06
 F test/malloc2.test e6e321db96d6c94cb18bf82ad7215070c41e624e
 F test/malloc3.test 9797d39eca7087a1022bcc0eb0b22215475c9698
 F test/malloc4.test 2e29d155eb4b4808019ef47eeedfcbe9e09e0f05
-F test/malloc5.test 4ebf827a8173e1429480a6b276d37e89c6ab96f0
+F test/malloc5.test 1bac8c0dd98c387460920c1190f0996c5c62ea66
 F test/manydb.test d81debbf5871242e3b5df1d3bb5e14c50431b6f8
 F test/memdb.test 1860e060be810bf0775bc57408a5b7c4954bcaea
 F test/memleak.test df2b2b96e77f8ba159a332299535b1e5f18e49ac
@@ -335,7 +335,7 @@ F www/tclsqlite.tcl bb0d1357328a42b1993d78573e587c6dcbc964b9
 F www/vdbe.tcl 87a31ace769f20d3627a64fa1fade7fed47b90d0
 F www/version3.tcl a99cf5f6d8bd4d5537584a2b342f0fb9fa601d8b
 F www/whentouse.tcl 97e2b5cd296f7d8057e11f44427dea8a4c2db513
-P cc963f8cfc6c704c645c627bffb8df21dfebffc6
-R 7000da8baf46b4c1ff76e715121c7c17
+P 82b81f69c78cb3f54634d9aea4f6a838474dc5e5
+R bcf9f7930a1367ea3da4936a55af71d7
 U danielk1977
-Z c505bc6b6a245c795a8be1eda400ccd9
+Z b19a6ec12413214a65f445404992c64a

manifest.uuid

@@ -1 +1 @@
-82b81f69c78cb3f54634d9aea4f6a838474dc5e5
+44f8e3139aa3ad3fcce9028565dd9ad23bbe62a2

src/btree.c

@@ -9,7 +9,7 @@
 **    May you share freely, never taking more than you give.
 **
 *************************************************************************
-** $Id: btree.c,v 1.287 2006/01/09 06:29:48 danielk1977 Exp $
+** $Id: btree.c,v 1.288 2006/01/09 09:59:49 danielk1977 Exp $
 **
 ** This file implements a external (disk-based) database using BTrees.
 ** For a detailed discussion of BTrees, refer to
@@ -6504,11 +6504,19 @@ int sqlite3BtreeLockTable(Btree *p, int iTab, u8 isWriteLock){
 ** Enable the shared pager and schema features.
 */
 int sqlite3_enable_shared_cache(int enable){
-  ThreadData *pTsd = sqlite3ThreadData();
-  if( pTsd->pPager ){
+  ThreadData *pTd = sqlite3ThreadData();
+  
+  /* It is only legal to call sqlite3_enable_shared_cache() when there
+  ** are no currently open b-trees that were opened by the calling thread.
+  ** This condition is only easy to detect if the shared-cache were 
+  ** previously enabled (and is being disabled). 
+  */
+  if( pTd->pBtree && !enable ){
+    assert( pTd->useSharedData );
     return SQLITE_MISUSE;
   }
-  pTsd->useSharedData = enable;
+
+  pTd->useSharedData = enable;
   return SQLITE_OK;
 }
 #endif

src/pager.c

@@ -18,7 +18,7 @@
 ** file simultaneously, or one process from reading the database while
 ** another is writing.
 **
-** @(#) $Id: pager.c,v 1.232 2006/01/09 06:29:49 danielk1977 Exp $
+** @(#) $Id: pager.c,v 1.233 2006/01/09 09:59:49 danielk1977 Exp $
 */
 #ifndef SQLITE_OMIT_DISKIO
 #include "sqliteInt.h"
@@ -1623,7 +1623,9 @@ int sqlite3pager_open(
   int useJournal = (flags & PAGER_OMIT_JOURNAL)==0;
   int noReadlock = (flags & PAGER_NO_READLOCK)!=0;
   char zTemp[SQLITE_TEMPNAME_SIZE];
+#ifndef SQLITE_OMIT_MEMORY_MANAGEMENT
   ThreadData *pTsd = sqlite3ThreadData();
+#endif
 
   /* If malloc() has already failed return SQLITE_NOMEM. Before even
   ** testing for this, set *ppPager to NULL so the caller knows the pager
@@ -1723,8 +1725,12 @@ int sqlite3pager_open(
   pPager->pBusyHandler = 0;
   memset(pPager->aHash, 0, sizeof(pPager->aHash));
   *ppPager = pPager;
+#ifndef SQLITE_OMIT_MEMORY_MANAGEMENT
+  if( pTsd->useMemoryManagement ){
     pPager->pNext = pTsd->pPager;
     pTsd->pPager = pPager;
+  }
+#endif
   return SQLITE_OK;
 }
 
@@ -2088,8 +2094,9 @@ int sqlite3pager_close(Pager *pPager){
 
 #ifndef SQLITE_OMIT_MEMORY_MANAGEMENT
   /* Remove the pager from the linked list of pagers starting at 
-  ** ThreadData.pPager.
+  ** ThreadData.pPager if memory-management is enabled.
   */
+  if( pTsd->useMemoryManagement ){
     if( pPager==pTsd->pPager ){
       pTsd->pPager = pPager->pNext;
     }else{
@@ -2097,6 +2104,7 @@ int sqlite3pager_close(Pager *pPager){
       for(pTmp = pTsd->pPager; pTmp->pNext!=pPager; pTmp=pTmp->pNext);
       pTmp->pNext = pPager->pNext;
     }
+  }
 #endif
 
   sqliteFree(pPager);

src/sqlite.h.in

@@ -12,7 +12,7 @@
 ** This header file defines the interface that the SQLite library
 ** presents to client programs.
 **
-** @(#) $Id: sqlite.h.in,v 1.152 2005/12/30 16:28:02 danielk1977 Exp $
+** @(#) $Id: sqlite.h.in,v 1.153 2006/01/09 09:59:49 danielk1977 Exp $
 */
 #ifndef _SQLITE3_H_
 #define _SQLITE3_H_
@@ -1276,21 +1276,6 @@ int sqlite3_get_autocommit(sqlite3*);
 */
 sqlite3 *sqlite3_db_handle(sqlite3_stmt*);
 
-/*
-** Place a "soft" limit on the amount of heap memory that may be allocated by
-** SQLite within the current thread. If an internal allocation is requested 
-** that would exceed the specified limit, sqlite3_release_memory() is invoked
-** one or more times to free up some space before the allocation is made.
-**
-** The limit is called "soft", because if sqlite3_release_memory() cannot free
-** sufficient memory to prevent the limit from being exceeded, the memory is
-** allocated anyway and the current operation proceeds.
-**
-** This function is only available if the library was compiled without the 
-** SQLITE_OMIT_MEMORY_MANAGEMENT option set.
-*/
-void sqlite3_soft_heap_limit(sqlite_int64);
-
 /*
 ** Register a callback function with the database connection identified by the 
 ** first argument to be invoked whenever a row is updated, inserted or deleted.
@@ -1336,8 +1321,6 @@ void *sqlite3_update_hook(
 */
 void *sqlite3_rollback_hook(sqlite3*, void(*)(void *), void*);
 
-int sqlite3_release_memory(int);
-
 /*
 ** This function is only available if the library is compiled without
 ** the SQLITE_OMIT_SHARED_CACHE macro defined. It is used to enable or
@@ -1346,6 +1329,40 @@ int sqlite3_release_memory(int);
 */
 int sqlite3_enable_shared_cache(int);
 
+/*
+** This function is only available if the library is compiled without
+** the SQLITE_OMIT_MEMORY_MANAGEMENT macro defined. It is used to enable or
+** disable (if the argument is true or false, respectively) the 
+** "memory management" features (accessed via the sqlite3_soft_heap_limit()
+** and sqlite3_release_memory() APIs).
+*/
+int sqlite3_enable_memory_management(int);
+
+/*
+** Attempt to free N bytes of heap memory by deallocating non-essential
+** memory allocations held by the database library (example: memory 
+** used to cache database pages to improve performance).
+**
+** This function is a no-op unless memory-management has been enabled.
+*/
+int sqlite3_release_memory(int);
+
+/*
+** Place a "soft" limit on the amount of heap memory that may be allocated by
+** SQLite within the current thread. If an internal allocation is requested 
+** that would exceed the specified limit, sqlite3_release_memory() is invoked
+** one or more times to free up some space before the allocation is made.
+**
+** The limit is called "soft", because if sqlite3_release_memory() cannot free
+** sufficient memory to prevent the limit from being exceeded, the memory is
+** allocated anyway and the current operation proceeds.
+**
+** This function is only available if the library was compiled without the 
+** SQLITE_OMIT_MEMORY_MANAGEMENT option set. It is a no-op unless 
+** memory-management has been enabled.
+*/
+void sqlite3_soft_heap_limit(sqlite_int64);
+
 /*
 ** Undo the hack that converts floating point types to integer for
 ** builds on processors without floating point support.

src/sqliteInt.h

@@ -11,7 +11,7 @@
 *************************************************************************
 ** Internal interface definitions for SQLite.
 **
-** @(#) $Id: sqliteInt.h,v 1.454 2006/01/09 06:29:49 danielk1977 Exp $
+** @(#) $Id: sqliteInt.h,v 1.455 2006/01/09 09:59:49 danielk1977 Exp $
 */
 #ifndef _SQLITEINT_H_
 #define _SQLITEINT_H_
@@ -294,6 +294,7 @@ struct ThreadData {
   u8 disableReleaseMemory; /* True to make sqlite3_release_memory() a no-op */
 
 #ifndef SQLITE_OMIT_MEMORY_MANAGEMENT
+  u8 useMemoryManagement;  /* True if memory-management is enabled */
   i64 nSoftHeapLimit;      /* Suggested max mem allocation.  No limit if <0 */
   i64 nAlloc;              /* Number of bytes currently allocated */
   Pager *pPager;           /* Linked list of all pagers in this thread */

src/test1.c

@@ -13,7 +13,7 @@
 ** is not included in the SQLite library.  It is used for automated
 ** testing of the SQLite library.
 **
-** $Id: test1.c,v 1.184 2006/01/09 06:29:49 danielk1977 Exp $
+** $Id: test1.c,v 1.185 2006/01/09 09:59:49 danielk1977 Exp $
 */
 #include "sqliteInt.h"
 #include "tcl.h"
@@ -903,21 +903,16 @@ static int sqlite_malloc_outstanding(
 ){
   extern int sqlite3OutstandingMallocs(Tcl_Interp *interp);
 
-  if( objc!=1 && objc!=2 ){
-    Tcl_WrongNumArgs(interp, 1, objv, "?-bytes?");
-    return TCL_ERROR;
-  }
-
+#ifndef SQLITE_OMIT_MEMORY_MANAGEMENT
   if( objc==2 ){
+    ThreadData *pTd = sqlite3ThreadData();
     const char *zArg = Tcl_GetString(objv[1]);
     if( 0==strcmp(zArg, "-bytes") ){
-      Tcl_SetObjResult(interp, Tcl_NewIntObj(sqlite3ThreadData()->nAlloc));
-#ifndef SQLITE_OMIT_MEMORY_MANAGEMENT
+      Tcl_SetObjResult(interp, Tcl_NewIntObj(pTd->nAlloc));
     }else if( 0==strcmp(zArg, "-maxbytes") ){
-      Tcl_SetObjResult(interp, Tcl_NewWideIntObj(sqlite3ThreadData()->nMaxAlloc));
+      Tcl_SetObjResult(interp, Tcl_NewWideIntObj(pTd->nMaxAlloc));
     }else if( 0==strcmp(zArg, "-clearmaxbytes") ){
-      sqlite3ThreadData()->nMaxAlloc = sqlite3ThreadData()->nAlloc;
-#endif
+      pTd->nMaxAlloc = pTd->nAlloc;
     }else{
       Tcl_AppendResult(interp, "bad option \"", zArg, 
         "\": must be -bytes, -maxbytes or -clearmaxbytes", 0
@@ -927,6 +922,12 @@ static int sqlite_malloc_outstanding(
 
     return TCL_OK;
   }
+#endif
+
+  if( objc!=1 ){
+    Tcl_WrongNumArgs(interp, 1, objv, "?-bytes?");
+    return TCL_ERROR;
+  }
 
   return sqlite3OutstandingMallocs(interp);
 }
@@ -934,20 +935,33 @@ static int sqlite_malloc_outstanding(
 
 /*
 ** Usage: sqlite3_enable_shared_cache      BOOLEAN
+** Usage: sqlite3_enable_memory_management BOOLEAN
 **
 */
-#ifndef SQLITE_OMIT_SHARED_CACHE
-static int test_enable_shared_cache(
-  ClientData clientData,
+#if !defined(SQLITE_OMIT_SHARED_CACHE)||!defined(SQLITE_OMIT_MEMORY_MANAGEMENT)
+static int test_enable(
+  ClientData clientData, /* Pointer to sqlite3_enable_XXX function */
   Tcl_Interp *interp,    /* The TCL interpreter that invoked this command */
   int objc,              /* Number of arguments */
   Tcl_Obj *CONST objv[]  /* Command arguments */
 ){
   int rc;
   int enable;
+  int ret = 0;
+  int (*xFunc)(int) = (int(*)(int))clientData;
   ThreadData *pTsd = sqlite3ThreadData();
-  Tcl_SetObjResult(interp, Tcl_NewBooleanObj(pTsd->useSharedData));
 
+#ifndef SQLITE_OMIT_SHARED_CACHE
+  if( xFunc==sqlite3_enable_shared_cache ){
+    ret = pTsd->useSharedData;
+  }else
+#endif
+#ifndef SQLITE_OMIT_MEMORY_MANAGEMENT
+  {
+    assert( xFunc==sqlite3_enable_memory_management );
+    ret = pTsd->useMemoryManagement;
+  }
+#endif
   if( objc!=2 ){
     Tcl_WrongNumArgs(interp, 1, objv, "BOOLEAN");
     return TCL_ERROR;
@@ -955,11 +969,12 @@ static int test_enable_shared_cache(
   if( Tcl_GetBooleanFromObj(interp, objv[1], &enable) ){
     return TCL_ERROR;
   }
-  rc = sqlite3_enable_shared_cache(enable);
+  rc = xFunc(enable);
   if( rc!=SQLITE_OK ){
     Tcl_SetResult(interp, (char *)sqlite3ErrStr(rc), TCL_STATIC);
     return TCL_ERROR;
   }
+  Tcl_SetObjResult(interp, Tcl_NewBooleanObj(ret));
   return TCL_OK;
 }
 #endif
@@ -3414,7 +3429,11 @@ int Sqlitetest1_Init(Tcl_Interp *interp){
      { "sqlite3_test_errstr",     test_errstr, 0             },
      { "tcl_variable_type",       tcl_variable_type, 0       },
 #ifndef SQLITE_OMIT_SHARED_CACHE
-     { "sqlite3_enable_shared_cache", test_enable_shared_cache, 0},
+     { "sqlite3_enable_shared_cache", test_enable, sqlite3_enable_shared_cache},
+#endif
+#ifndef SQLITE_OMIT_MEMORY_MANAGEMENT
+     { "sqlite3_enable_memory_management", test_enable, 
+       sqlite3_enable_memory_management},
 #endif
   };
   static int bitmask_size = sizeof(Bitmask)*8;

src/util.c

@@ -14,7 +14,7 @@
 ** This file contains functions for allocating memory, comparing
 ** strings, and stuff like that.
 **
-** $Id: util.c,v 1.163 2006/01/09 06:29:49 danielk1977 Exp $
+** $Id: util.c,v 1.164 2006/01/09 09:59:49 danielk1977 Exp $
 */
 #include "sqliteInt.h"
 #include "os.h"
@@ -529,7 +529,7 @@ static void handleSoftLimit(int n){
   }
 }
 #else
-#define handleSoftLimit()
+#define handleSoftLimit(x)
 #endif
 
 /*
@@ -1307,7 +1307,9 @@ void *sqlite3TextToPtr(const char *z){
 ThreadData *sqlite3ThreadData(){
   ThreadData *pTsd = sqlite3OsThreadSpecificData(sizeof(ThreadData));
   if( pTsd && !pTsd->isInit ){
+#ifndef SQLITE_OMIT_MEMORY_MANAGEMENT
     pTsd->nSoftHeapLimit = -1;
+#endif
 #ifndef NDEBUG
     pTsd->mallocAllowed = 1;
 #endif
@@ -1324,6 +1326,25 @@ void sqlite3MallocClearFailed(){
   sqlite3ThreadData()->mallocFailed = 0;
 }
 
+#ifndef SQLITE_OMIT_MEMORY_MANAGEMENT
+/*
+** Enable the shared pager and schema features.
+*/
+int sqlite3_enable_memory_management(int enable){
+  ThreadData *pTsd = sqlite3ThreadData();
+
+  /* It is only legal to call sqlite3_enable_memory_management() when there
+  ** are no currently open connections that were opened by the calling 
+  ** thread. This condition is only easy to detect if the feature were
+  ** previously enabled (and is being disabled). 
+  */
+  if( pTsd->pPager && !enable ){
+    return SQLITE_MISUSE;
+  }
+  pTsd->useMemoryManagement = enable;
+  return SQLITE_OK;
+}
+#endif
 
 #ifndef NDEBUG
 /*

test/malloc5.test

@@ -12,15 +12,17 @@
 # This file contains test cases focused on the two memory-management APIs, 
 # sqlite3_soft_heap_limit() and sqlite3_release_memory().
 #
-# $Id: malloc5.test,v 1.4 2006/01/05 15:50:07 drh Exp $
+# $Id: malloc5.test,v 1.5 2006/01/09 09:59:49 danielk1977 Exp $
 
 #---------------------------------------------------------------------------
 # NOTES ON EXPECTED BEHAVIOUR
 #
 #---------------------------------------------------------------------------
 
+
 set testdir [file dirname $argv0]
 source $testdir/tester.tcl
+db close
 
 # Only run these tests if memory debugging is turned on.
 if {[info command sqlite_malloc_stat]==""} {
@@ -29,6 +31,15 @@ if {[info command sqlite_malloc_stat]==""} {
    return
 }
 
+# Skip these tests if OMIT_MEMORY_MANAGEMENT was defined at compile time.
+ifcapable !memorymanage {
+   finish_test
+   return
+}
+
+sqlite3_enable_memory_management 1
+sqlite3 db test.db
+
 do_test malloc5-1.1 {
   # Simplest possible test. Call sqlite3_release_memory when there is exactly
   # one unused page in a single pager cache. This test case set's the 
@@ -205,5 +216,8 @@ do_test malloc5-4.3 {
 
 # Restore the soft heap limit.
 sqlite3_soft_heap_limit $::soft_limit
-
 finish_test
+
+catch {db close}
+sqlite3_enable_memory_management 0
+