000001 /*
000002 ** 2008 June 18
000003 **
000004 ** The author disclaims copyright to this source code. In place of
000005 ** a legal notice, here is a blessing:
000006 **
000007 ** May you do good and not evil.
000008 ** May you find forgiveness for yourself and forgive others.
000009 ** May you share freely, never taking more than you give.
000010 **
000011 *************************************************************************
000012 **
000013 ** This module implements the sqlite3_status() interface and related
000014 ** functionality.
000015 */
000016 #include "sqliteInt.h"
000017 #include "vdbeInt.h"
000018
000019 /*
000020 ** Variables in which to record status information.
000021 */
000022 #if SQLITE_PTRSIZE>4
000023 typedef sqlite3_int64 sqlite3StatValueType;
000024 #else
000025 typedef u32 sqlite3StatValueType;
000026 #endif
000027 typedef struct sqlite3StatType sqlite3StatType;
000028 static SQLITE_WSD struct sqlite3StatType {
000029 sqlite3StatValueType nowValue[10]; /* Current value */
000030 sqlite3StatValueType mxValue[10]; /* Maximum value */
000031 } sqlite3Stat = { {0,}, {0,} };
000032
000033 /*
000034 ** Elements of sqlite3Stat[] are protected by either the memory allocator
000035 ** mutex, or by the pcache1 mutex. The following array determines which.
000036 */
000037 static const char statMutex[] = {
000038 0, /* SQLITE_STATUS_MEMORY_USED */
000039 1, /* SQLITE_STATUS_PAGECACHE_USED */
000040 1, /* SQLITE_STATUS_PAGECACHE_OVERFLOW */
000041 0, /* SQLITE_STATUS_SCRATCH_USED */
000042 0, /* SQLITE_STATUS_SCRATCH_OVERFLOW */
000043 0, /* SQLITE_STATUS_MALLOC_SIZE */
000044 0, /* SQLITE_STATUS_PARSER_STACK */
000045 1, /* SQLITE_STATUS_PAGECACHE_SIZE */
000046 0, /* SQLITE_STATUS_SCRATCH_SIZE */
000047 0, /* SQLITE_STATUS_MALLOC_COUNT */
000048 };
000049
000050
000051 /* The "wsdStat" macro will resolve to the status information
000052 ** state vector. If writable static data is unsupported on the target,
000053 ** we have to locate the state vector at run-time. In the more common
000054 ** case where writable static data is supported, wsdStat can refer directly
000055 ** to the "sqlite3Stat" state vector declared above.
000056 */
000057 #ifdef SQLITE_OMIT_WSD
000058 # define wsdStatInit sqlite3StatType *x = &GLOBAL(sqlite3StatType,sqlite3Stat)
000059 # define wsdStat x[0]
000060 #else
000061 # define wsdStatInit
000062 # define wsdStat sqlite3Stat
000063 #endif
000064
000065 /*
000066 ** Return the current value of a status parameter. The caller must
000067 ** be holding the appropriate mutex.
000068 */
000069 sqlite3_int64 sqlite3StatusValue(int op){
000070 wsdStatInit;
000071 assert( op>=0 && op<ArraySize(wsdStat.nowValue) );
000072 assert( op>=0 && op<ArraySize(statMutex) );
000073 assert( sqlite3_mutex_held(statMutex[op] ? sqlite3Pcache1Mutex()
000074 : sqlite3MallocMutex()) );
000075 return wsdStat.nowValue[op];
000076 }
000077
000078 /*
000079 ** Add N to the value of a status record. The caller must hold the
000080 ** appropriate mutex. (Locking is checked by assert()).
000081 **
000082 ** The StatusUp() routine can accept positive or negative values for N.
000083 ** The value of N is added to the current status value and the high-water
000084 ** mark is adjusted if necessary.
000085 **
000086 ** The StatusDown() routine lowers the current value by N. The highwater
000087 ** mark is unchanged. N must be non-negative for StatusDown().
000088 */
000089 void sqlite3StatusUp(int op, int N){
000090 wsdStatInit;
000091 assert( op>=0 && op<ArraySize(wsdStat.nowValue) );
000092 assert( op>=0 && op<ArraySize(statMutex) );
000093 assert( sqlite3_mutex_held(statMutex[op] ? sqlite3Pcache1Mutex()
000094 : sqlite3MallocMutex()) );
000095 wsdStat.nowValue[op] += N;
000096 if( wsdStat.nowValue[op]>wsdStat.mxValue[op] ){
000097 wsdStat.mxValue[op] = wsdStat.nowValue[op];
000098 }
000099 }
000100 void sqlite3StatusDown(int op, int N){
000101 wsdStatInit;
000102 assert( N>=0 );
000103 assert( op>=0 && op<ArraySize(statMutex) );
000104 assert( sqlite3_mutex_held(statMutex[op] ? sqlite3Pcache1Mutex()
000105 : sqlite3MallocMutex()) );
000106 assert( op>=0 && op<ArraySize(wsdStat.nowValue) );
000107 wsdStat.nowValue[op] -= N;
000108 }
000109
000110 /*
000111 ** Adjust the highwater mark if necessary.
000112 ** The caller must hold the appropriate mutex.
000113 */
000114 void sqlite3StatusHighwater(int op, int X){
000115 sqlite3StatValueType newValue;
000116 wsdStatInit;
000117 assert( X>=0 );
000118 newValue = (sqlite3StatValueType)X;
000119 assert( op>=0 && op<ArraySize(wsdStat.nowValue) );
000120 assert( op>=0 && op<ArraySize(statMutex) );
000121 assert( sqlite3_mutex_held(statMutex[op] ? sqlite3Pcache1Mutex()
000122 : sqlite3MallocMutex()) );
000123 assert( op==SQLITE_STATUS_MALLOC_SIZE
000124 || op==SQLITE_STATUS_PAGECACHE_SIZE
000125 || op==SQLITE_STATUS_PARSER_STACK );
000126 if( newValue>wsdStat.mxValue[op] ){
000127 wsdStat.mxValue[op] = newValue;
000128 }
000129 }
000130
000131 /*
000132 ** Query status information.
000133 */
000134 int sqlite3_status64(
000135 int op,
000136 sqlite3_int64 *pCurrent,
000137 sqlite3_int64 *pHighwater,
000138 int resetFlag
000139 ){
000140 sqlite3_mutex *pMutex;
000141 wsdStatInit;
000142 if( op<0 || op>=ArraySize(wsdStat.nowValue) ){
000143 return SQLITE_MISUSE_BKPT;
000144 }
000145 #ifdef SQLITE_ENABLE_API_ARMOR
000146 if( pCurrent==0 || pHighwater==0 ) return SQLITE_MISUSE_BKPT;
000147 #endif
000148 pMutex = statMutex[op] ? sqlite3Pcache1Mutex() : sqlite3MallocMutex();
000149 sqlite3_mutex_enter(pMutex);
000150 *pCurrent = wsdStat.nowValue[op];
000151 *pHighwater = wsdStat.mxValue[op];
000152 if( resetFlag ){
000153 wsdStat.mxValue[op] = wsdStat.nowValue[op];
000154 }
000155 sqlite3_mutex_leave(pMutex);
000156 (void)pMutex; /* Prevent warning when SQLITE_THREADSAFE=0 */
000157 return SQLITE_OK;
000158 }
000159 int sqlite3_status(int op, int *pCurrent, int *pHighwater, int resetFlag){
000160 sqlite3_int64 iCur = 0, iHwtr = 0;
000161 int rc;
000162 #ifdef SQLITE_ENABLE_API_ARMOR
000163 if( pCurrent==0 || pHighwater==0 ) return SQLITE_MISUSE_BKPT;
000164 #endif
000165 rc = sqlite3_status64(op, &iCur, &iHwtr, resetFlag);
000166 if( rc==0 ){
000167 *pCurrent = (int)iCur;
000168 *pHighwater = (int)iHwtr;
000169 }
000170 return rc;
000171 }
000172
000173 /*
000174 ** Return the number of LookasideSlot elements on the linked list
000175 */
000176 static u32 countLookasideSlots(LookasideSlot *p){
000177 u32 cnt = 0;
000178 while( p ){
000179 p = p->pNext;
000180 cnt++;
000181 }
000182 return cnt;
000183 }
000184
000185 /*
000186 ** Count the number of slots of lookaside memory that are outstanding
000187 */
000188 int sqlite3LookasideUsed(sqlite3 *db, int *pHighwater){
000189 u32 nInit = countLookasideSlots(db->lookaside.pInit);
000190 u32 nFree = countLookasideSlots(db->lookaside.pFree);
000191 #ifndef SQLITE_OMIT_TWOSIZE_LOOKASIDE
000192 nInit += countLookasideSlots(db->lookaside.pSmallInit);
000193 nFree += countLookasideSlots(db->lookaside.pSmallFree);
000194 #endif /* SQLITE_OMIT_TWOSIZE_LOOKASIDE */
000195 if( pHighwater ) *pHighwater = db->lookaside.nSlot - nInit;
000196 return db->lookaside.nSlot - (nInit+nFree);
000197 }
000198
000199 /*
000200 ** Query status information for a single database connection
000201 */
000202 int sqlite3_db_status(
000203 sqlite3 *db, /* The database connection whose status is desired */
000204 int op, /* Status verb */
000205 int *pCurrent, /* Write current value here */
000206 int *pHighwater, /* Write high-water mark here */
000207 int resetFlag /* Reset high-water mark if true */
000208 ){
000209 int rc = SQLITE_OK; /* Return code */
000210 #ifdef SQLITE_ENABLE_API_ARMOR
000211 if( !sqlite3SafetyCheckOk(db) || pCurrent==0|| pHighwater==0 ){
000212 return SQLITE_MISUSE_BKPT;
000213 }
000214 #endif
000215 sqlite3_mutex_enter(db->mutex);
000216 switch( op ){
000217 case SQLITE_DBSTATUS_LOOKASIDE_USED: {
000218 *pCurrent = sqlite3LookasideUsed(db, pHighwater);
000219 if( resetFlag ){
000220 LookasideSlot *p = db->lookaside.pFree;
000221 if( p ){
000222 while( p->pNext ) p = p->pNext;
000223 p->pNext = db->lookaside.pInit;
000224 db->lookaside.pInit = db->lookaside.pFree;
000225 db->lookaside.pFree = 0;
000226 }
000227 #ifndef SQLITE_OMIT_TWOSIZE_LOOKASIDE
000228 p = db->lookaside.pSmallFree;
000229 if( p ){
000230 while( p->pNext ) p = p->pNext;
000231 p->pNext = db->lookaside.pSmallInit;
000232 db->lookaside.pSmallInit = db->lookaside.pSmallFree;
000233 db->lookaside.pSmallFree = 0;
000234 }
000235 #endif
000236 }
000237 break;
000238 }
000239
000240 case SQLITE_DBSTATUS_LOOKASIDE_HIT:
000241 case SQLITE_DBSTATUS_LOOKASIDE_MISS_SIZE:
000242 case SQLITE_DBSTATUS_LOOKASIDE_MISS_FULL: {
000243 testcase( op==SQLITE_DBSTATUS_LOOKASIDE_HIT );
000244 testcase( op==SQLITE_DBSTATUS_LOOKASIDE_MISS_SIZE );
000245 testcase( op==SQLITE_DBSTATUS_LOOKASIDE_MISS_FULL );
000246 assert( (op-SQLITE_DBSTATUS_LOOKASIDE_HIT)>=0 );
000247 assert( (op-SQLITE_DBSTATUS_LOOKASIDE_HIT)<3 );
000248 *pCurrent = 0;
000249 *pHighwater = db->lookaside.anStat[op - SQLITE_DBSTATUS_LOOKASIDE_HIT];
000250 if( resetFlag ){
000251 db->lookaside.anStat[op - SQLITE_DBSTATUS_LOOKASIDE_HIT] = 0;
000252 }
000253 break;
000254 }
000255
000256 /*
000257 ** Return an approximation for the amount of memory currently used
000258 ** by all pagers associated with the given database connection. The
000259 ** highwater mark is meaningless and is returned as zero.
000260 */
000261 case SQLITE_DBSTATUS_CACHE_USED_SHARED:
000262 case SQLITE_DBSTATUS_CACHE_USED: {
000263 int totalUsed = 0;
000264 int i;
000265 sqlite3BtreeEnterAll(db);
000266 for(i=0; i<db->nDb; i++){
000267 Btree *pBt = db->aDb[i].pBt;
000268 if( pBt ){
000269 Pager *pPager = sqlite3BtreePager(pBt);
000270 int nByte = sqlite3PagerMemUsed(pPager);
000271 if( op==SQLITE_DBSTATUS_CACHE_USED_SHARED ){
000272 nByte = nByte / sqlite3BtreeConnectionCount(pBt);
000273 }
000274 totalUsed += nByte;
000275 }
000276 }
000277 sqlite3BtreeLeaveAll(db);
000278 *pCurrent = totalUsed;
000279 *pHighwater = 0;
000280 break;
000281 }
000282
000283 /*
000284 ** *pCurrent gets an accurate estimate of the amount of memory used
000285 ** to store the schema for all databases (main, temp, and any ATTACHed
000286 ** databases. *pHighwater is set to zero.
000287 */
000288 case SQLITE_DBSTATUS_SCHEMA_USED: {
000289 int i; /* Used to iterate through schemas */
000290 int nByte = 0; /* Used to accumulate return value */
000291
000292 sqlite3BtreeEnterAll(db);
000293 db->pnBytesFreed = &nByte;
000294 assert( db->lookaside.pEnd==db->lookaside.pTrueEnd );
000295 db->lookaside.pEnd = db->lookaside.pStart;
000296 for(i=0; i<db->nDb; i++){
000297 Schema *pSchema = db->aDb[i].pSchema;
000298 if( ALWAYS(pSchema!=0) ){
000299 HashElem *p;
000300
000301 nByte += sqlite3GlobalConfig.m.xRoundup(sizeof(HashElem)) * (
000302 pSchema->tblHash.count
000303 + pSchema->trigHash.count
000304 + pSchema->idxHash.count
000305 + pSchema->fkeyHash.count
000306 );
000307 nByte += sqlite3_msize(pSchema->tblHash.ht);
000308 nByte += sqlite3_msize(pSchema->trigHash.ht);
000309 nByte += sqlite3_msize(pSchema->idxHash.ht);
000310 nByte += sqlite3_msize(pSchema->fkeyHash.ht);
000311
000312 for(p=sqliteHashFirst(&pSchema->trigHash); p; p=sqliteHashNext(p)){
000313 sqlite3DeleteTrigger(db, (Trigger*)sqliteHashData(p));
000314 }
000315 for(p=sqliteHashFirst(&pSchema->tblHash); p; p=sqliteHashNext(p)){
000316 sqlite3DeleteTable(db, (Table *)sqliteHashData(p));
000317 }
000318 }
000319 }
000320 db->pnBytesFreed = 0;
000321 db->lookaside.pEnd = db->lookaside.pTrueEnd;
000322 sqlite3BtreeLeaveAll(db);
000323
000324 *pHighwater = 0;
000325 *pCurrent = nByte;
000326 break;
000327 }
000328
000329 /*
000330 ** *pCurrent gets an accurate estimate of the amount of memory used
000331 ** to store all prepared statements.
000332 ** *pHighwater is set to zero.
000333 */
000334 case SQLITE_DBSTATUS_STMT_USED: {
000335 struct Vdbe *pVdbe; /* Used to iterate through VMs */
000336 int nByte = 0; /* Used to accumulate return value */
000337
000338 db->pnBytesFreed = &nByte;
000339 assert( db->lookaside.pEnd==db->lookaside.pTrueEnd );
000340 db->lookaside.pEnd = db->lookaside.pStart;
000341 for(pVdbe=db->pVdbe; pVdbe; pVdbe=pVdbe->pVNext){
000342 sqlite3VdbeDelete(pVdbe);
000343 }
000344 db->lookaside.pEnd = db->lookaside.pTrueEnd;
000345 db->pnBytesFreed = 0;
000346
000347 *pHighwater = 0; /* IMP: R-64479-57858 */
000348 *pCurrent = nByte;
000349
000350 break;
000351 }
000352
000353 /*
000354 ** Set *pCurrent to the total cache hits or misses encountered by all
000355 ** pagers the database handle is connected to. *pHighwater is always set
000356 ** to zero.
000357 */
000358 case SQLITE_DBSTATUS_CACHE_SPILL:
000359 op = SQLITE_DBSTATUS_CACHE_WRITE+1;
000360 /* no break */ deliberate_fall_through
000361 case SQLITE_DBSTATUS_CACHE_HIT:
000362 case SQLITE_DBSTATUS_CACHE_MISS:
000363 case SQLITE_DBSTATUS_CACHE_WRITE:{
000364 int i;
000365 int nRet = 0;
000366 assert( SQLITE_DBSTATUS_CACHE_MISS==SQLITE_DBSTATUS_CACHE_HIT+1 );
000367 assert( SQLITE_DBSTATUS_CACHE_WRITE==SQLITE_DBSTATUS_CACHE_HIT+2 );
000368
000369 for(i=0; i<db->nDb; i++){
000370 if( db->aDb[i].pBt ){
000371 Pager *pPager = sqlite3BtreePager(db->aDb[i].pBt);
000372 sqlite3PagerCacheStat(pPager, op, resetFlag, &nRet);
000373 }
000374 }
000375 *pHighwater = 0; /* IMP: R-42420-56072 */
000376 /* IMP: R-54100-20147 */
000377 /* IMP: R-29431-39229 */
000378 *pCurrent = nRet;
000379 break;
000380 }
000381
000382 /* Set *pCurrent to non-zero if there are unresolved deferred foreign
000383 ** key constraints. Set *pCurrent to zero if all foreign key constraints
000384 ** have been satisfied. The *pHighwater is always set to zero.
000385 */
000386 case SQLITE_DBSTATUS_DEFERRED_FKS: {
000387 *pHighwater = 0; /* IMP: R-11967-56545 */
000388 *pCurrent = db->nDeferredImmCons>0 || db->nDeferredCons>0;
000389 break;
000390 }
000391
000392 default: {
000393 rc = SQLITE_ERROR;
000394 }
000395 }
000396 sqlite3_mutex_leave(db->mutex);
000397 return rc;
000398 }