1 /* 2 ** 2008 June 18 3 ** 4 ** The author disclaims copyright to this source code. In place of 5 ** a legal notice, here is a blessing: 6 ** 7 ** May you do good and not evil. 8 ** May you find forgiveness for yourself and forgive others. 9 ** May you share freely, never taking more than you give. 10 ** 11 ************************************************************************* 12 ** 13 ** This module implements the sqlite3_status() interface and related 14 ** functionality. 15 */ 16 #include "sqliteInt.h" 17 #include "vdbeInt.h" 18 19 /* 20 ** Variables in which to record status information. 21 */ 22 #if SQLITE_PTRSIZE>4 23 typedef sqlite3_int64 sqlite3StatValueType; 24 #else 25 typedef u32 sqlite3StatValueType; 26 #endif 27 typedef struct sqlite3StatType sqlite3StatType; 28 static SQLITE_WSD struct sqlite3StatType { 29 sqlite3StatValueType nowValue[10]; /* Current value */ 30 sqlite3StatValueType mxValue[10]; /* Maximum value */ 31 } sqlite3Stat = { {0,}, {0,} }; 32 33 /* 34 ** Elements of sqlite3Stat[] are protected by either the memory allocator 35 ** mutex, or by the pcache1 mutex. The following array determines which. 36 */ 37 static const char statMutex[] = { 38 0, /* SQLITE_STATUS_MEMORY_USED */ 39 1, /* SQLITE_STATUS_PAGECACHE_USED */ 40 1, /* SQLITE_STATUS_PAGECACHE_OVERFLOW */ 41 0, /* SQLITE_STATUS_SCRATCH_USED */ 42 0, /* SQLITE_STATUS_SCRATCH_OVERFLOW */ 43 0, /* SQLITE_STATUS_MALLOC_SIZE */ 44 0, /* SQLITE_STATUS_PARSER_STACK */ 45 1, /* SQLITE_STATUS_PAGECACHE_SIZE */ 46 0, /* SQLITE_STATUS_SCRATCH_SIZE */ 47 0, /* SQLITE_STATUS_MALLOC_COUNT */ 48 }; 49 50 51 /* The "wsdStat" macro will resolve to the status information 52 ** state vector. If writable static data is unsupported on the target, 53 ** we have to locate the state vector at run-time. In the more common 54 ** case where writable static data is supported, wsdStat can refer directly 55 ** to the "sqlite3Stat" state vector declared above. 56 */ 57 #ifdef SQLITE_OMIT_WSD 58 # define wsdStatInit sqlite3StatType *x = &GLOBAL(sqlite3StatType,sqlite3Stat) 59 # define wsdStat x[0] 60 #else 61 # define wsdStatInit 62 # define wsdStat sqlite3Stat 63 #endif 64 65 /* 66 ** Return the current value of a status parameter. The caller must 67 ** be holding the appropriate mutex. 68 */ 69 sqlite3_int64 sqlite3StatusValue(int op){ 70 wsdStatInit; 71 assert( op>=0 && op<ArraySize(wsdStat.nowValue) ); 72 assert( op>=0 && op<ArraySize(statMutex) ); 73 assert( sqlite3_mutex_held(statMutex[op] ? sqlite3Pcache1Mutex() 74 : sqlite3MallocMutex()) ); 75 return wsdStat.nowValue[op]; 76 } 77 78 /* 79 ** Add N to the value of a status record. The caller must hold the 80 ** appropriate mutex. (Locking is checked by assert()). 81 ** 82 ** The StatusUp() routine can accept positive or negative values for N. 83 ** The value of N is added to the current status value and the high-water 84 ** mark is adjusted if necessary. 85 ** 86 ** The StatusDown() routine lowers the current value by N. The highwater 87 ** mark is unchanged. N must be non-negative for StatusDown(). 88 */ 89 void sqlite3StatusUp(int op, int N){ 90 wsdStatInit; 91 assert( op>=0 && op<ArraySize(wsdStat.nowValue) ); 92 assert( op>=0 && op<ArraySize(statMutex) ); 93 assert( sqlite3_mutex_held(statMutex[op] ? sqlite3Pcache1Mutex() 94 : sqlite3MallocMutex()) ); 95 wsdStat.nowValue[op] += N; 96 if( wsdStat.nowValue[op]>wsdStat.mxValue[op] ){ 97 wsdStat.mxValue[op] = wsdStat.nowValue[op]; 98 } 99 } 100 void sqlite3StatusDown(int op, int N){ 101 wsdStatInit; 102 assert( N>=0 ); 103 assert( op>=0 && op<ArraySize(statMutex) ); 104 assert( sqlite3_mutex_held(statMutex[op] ? sqlite3Pcache1Mutex() 105 : sqlite3MallocMutex()) ); 106 assert( op>=0 && op<ArraySize(wsdStat.nowValue) ); 107 wsdStat.nowValue[op] -= N; 108 } 109 110 /* 111 ** Adjust the highwater mark if necessary. 112 ** The caller must hold the appropriate mutex. 113 */ 114 void sqlite3StatusHighwater(int op, int X){ 115 sqlite3StatValueType newValue; 116 wsdStatInit; 117 assert( X>=0 ); 118 newValue = (sqlite3StatValueType)X; 119 assert( op>=0 && op<ArraySize(wsdStat.nowValue) ); 120 assert( op>=0 && op<ArraySize(statMutex) ); 121 assert( sqlite3_mutex_held(statMutex[op] ? sqlite3Pcache1Mutex() 122 : sqlite3MallocMutex()) ); 123 assert( op==SQLITE_STATUS_MALLOC_SIZE 124 || op==SQLITE_STATUS_PAGECACHE_SIZE 125 || op==SQLITE_STATUS_PARSER_STACK ); 126 if( newValue>wsdStat.mxValue[op] ){ 127 wsdStat.mxValue[op] = newValue; 128 } 129 } 130 131 /* 132 ** Query status information. 133 */ 134 int sqlite3_status64( 135 int op, 136 sqlite3_int64 *pCurrent, 137 sqlite3_int64 *pHighwater, 138 int resetFlag 139 ){ 140 sqlite3_mutex *pMutex; 141 wsdStatInit; 142 if( op<0 || op>=ArraySize(wsdStat.nowValue) ){ 143 return SQLITE_MISUSE_BKPT; 144 } 145 #ifdef SQLITE_ENABLE_API_ARMOR 146 if( pCurrent==0 || pHighwater==0 ) return SQLITE_MISUSE_BKPT; 147 #endif 148 pMutex = statMutex[op] ? sqlite3Pcache1Mutex() : sqlite3MallocMutex(); 149 sqlite3_mutex_enter(pMutex); 150 *pCurrent = wsdStat.nowValue[op]; 151 *pHighwater = wsdStat.mxValue[op]; 152 if( resetFlag ){ 153 wsdStat.mxValue[op] = wsdStat.nowValue[op]; 154 } 155 sqlite3_mutex_leave(pMutex); 156 (void)pMutex; /* Prevent warning when SQLITE_THREADSAFE=0 */ 157 return SQLITE_OK; 158 } 159 int sqlite3_status(int op, int *pCurrent, int *pHighwater, int resetFlag){ 160 sqlite3_int64 iCur = 0, iHwtr = 0; 161 int rc; 162 #ifdef SQLITE_ENABLE_API_ARMOR 163 if( pCurrent==0 || pHighwater==0 ) return SQLITE_MISUSE_BKPT; 164 #endif 165 rc = sqlite3_status64(op, &iCur, &iHwtr, resetFlag); 166 if( rc==0 ){ 167 *pCurrent = (int)iCur; 168 *pHighwater = (int)iHwtr; 169 } 170 return rc; 171 } 172 173 /* 174 ** Return the number of LookasideSlot elements on the linked list 175 */ 176 static u32 countLookasideSlots(LookasideSlot *p){ 177 u32 cnt = 0; 178 while( p ){ 179 p = p->pNext; 180 cnt++; 181 } 182 return cnt; 183 } 184 185 /* 186 ** Count the number of slots of lookaside memory that are outstanding 187 */ 188 int sqlite3LookasideUsed(sqlite3 *db, int *pHighwater){ 189 u32 nInit = countLookasideSlots(db->lookaside.pInit); 190 u32 nFree = countLookasideSlots(db->lookaside.pFree); 191 if( pHighwater ) *pHighwater = db->lookaside.nSlot - nInit; 192 return db->lookaside.nSlot - (nInit+nFree); 193 } 194 195 /* 196 ** Query status information for a single database connection 197 */ 198 int sqlite3_db_status( 199 sqlite3 *db, /* The database connection whose status is desired */ 200 int op, /* Status verb */ 201 int *pCurrent, /* Write current value here */ 202 int *pHighwater, /* Write high-water mark here */ 203 int resetFlag /* Reset high-water mark if true */ 204 ){ 205 int rc = SQLITE_OK; /* Return code */ 206 #ifdef SQLITE_ENABLE_API_ARMOR 207 if( !sqlite3SafetyCheckOk(db) || pCurrent==0|| pHighwater==0 ){ 208 return SQLITE_MISUSE_BKPT; 209 } 210 #endif 211 sqlite3_mutex_enter(db->mutex); 212 switch( op ){ 213 case SQLITE_DBSTATUS_LOOKASIDE_USED: { 214 *pCurrent = sqlite3LookasideUsed(db, pHighwater); 215 if( resetFlag ){ 216 LookasideSlot *p = db->lookaside.pFree; 217 if( p ){ 218 while( p->pNext ) p = p->pNext; 219 p->pNext = db->lookaside.pInit; 220 db->lookaside.pInit = db->lookaside.pFree; 221 db->lookaside.pFree = 0; 222 } 223 } 224 break; 225 } 226 227 case SQLITE_DBSTATUS_LOOKASIDE_HIT: 228 case SQLITE_DBSTATUS_LOOKASIDE_MISS_SIZE: 229 case SQLITE_DBSTATUS_LOOKASIDE_MISS_FULL: { 230 testcase( op==SQLITE_DBSTATUS_LOOKASIDE_HIT ); 231 testcase( op==SQLITE_DBSTATUS_LOOKASIDE_MISS_SIZE ); 232 testcase( op==SQLITE_DBSTATUS_LOOKASIDE_MISS_FULL ); 233 assert( (op-SQLITE_DBSTATUS_LOOKASIDE_HIT)>=0 ); 234 assert( (op-SQLITE_DBSTATUS_LOOKASIDE_HIT)<3 ); 235 *pCurrent = 0; 236 *pHighwater = db->lookaside.anStat[op - SQLITE_DBSTATUS_LOOKASIDE_HIT]; 237 if( resetFlag ){ 238 db->lookaside.anStat[op - SQLITE_DBSTATUS_LOOKASIDE_HIT] = 0; 239 } 240 break; 241 } 242 243 /* 244 ** Return an approximation for the amount of memory currently used 245 ** by all pagers associated with the given database connection. The 246 ** highwater mark is meaningless and is returned as zero. 247 */ 248 case SQLITE_DBSTATUS_CACHE_USED_SHARED: 249 case SQLITE_DBSTATUS_CACHE_USED: { 250 int totalUsed = 0; 251 int i; 252 sqlite3BtreeEnterAll(db); 253 for(i=0; i<db->nDb; i++){ 254 Btree *pBt = db->aDb[i].pBt; 255 if( pBt ){ 256 Pager *pPager = sqlite3BtreePager(pBt); 257 int nByte = sqlite3PagerMemUsed(pPager); 258 if( op==SQLITE_DBSTATUS_CACHE_USED_SHARED ){ 259 nByte = nByte / sqlite3BtreeConnectionCount(pBt); 260 } 261 totalUsed += nByte; 262 } 263 } 264 sqlite3BtreeLeaveAll(db); 265 *pCurrent = totalUsed; 266 *pHighwater = 0; 267 break; 268 } 269 270 /* 271 ** *pCurrent gets an accurate estimate of the amount of memory used 272 ** to store the schema for all databases (main, temp, and any ATTACHed 273 ** databases. *pHighwater is set to zero. 274 */ 275 case SQLITE_DBSTATUS_SCHEMA_USED: { 276 int i; /* Used to iterate through schemas */ 277 int nByte = 0; /* Used to accumulate return value */ 278 279 sqlite3BtreeEnterAll(db); 280 db->pnBytesFreed = &nByte; 281 for(i=0; i<db->nDb; i++){ 282 Schema *pSchema = db->aDb[i].pSchema; 283 if( ALWAYS(pSchema!=0) ){ 284 HashElem *p; 285 286 nByte += sqlite3GlobalConfig.m.xRoundup(sizeof(HashElem)) * ( 287 pSchema->tblHash.count 288 + pSchema->trigHash.count 289 + pSchema->idxHash.count 290 + pSchema->fkeyHash.count 291 ); 292 nByte += sqlite3_msize(pSchema->tblHash.ht); 293 nByte += sqlite3_msize(pSchema->trigHash.ht); 294 nByte += sqlite3_msize(pSchema->idxHash.ht); 295 nByte += sqlite3_msize(pSchema->fkeyHash.ht); 296 297 for(p=sqliteHashFirst(&pSchema->trigHash); p; p=sqliteHashNext(p)){ 298 sqlite3DeleteTrigger(db, (Trigger*)sqliteHashData(p)); 299 } 300 for(p=sqliteHashFirst(&pSchema->tblHash); p; p=sqliteHashNext(p)){ 301 sqlite3DeleteTable(db, (Table *)sqliteHashData(p)); 302 } 303 } 304 } 305 db->pnBytesFreed = 0; 306 sqlite3BtreeLeaveAll(db); 307 308 *pHighwater = 0; 309 *pCurrent = nByte; 310 break; 311 } 312 313 /* 314 ** *pCurrent gets an accurate estimate of the amount of memory used 315 ** to store all prepared statements. 316 ** *pHighwater is set to zero. 317 */ 318 case SQLITE_DBSTATUS_STMT_USED: { 319 struct Vdbe *pVdbe; /* Used to iterate through VMs */ 320 int nByte = 0; /* Used to accumulate return value */ 321 322 db->pnBytesFreed = &nByte; 323 for(pVdbe=db->pVdbe; pVdbe; pVdbe=pVdbe->pNext){ 324 sqlite3VdbeClearObject(db, pVdbe); 325 sqlite3DbFree(db, pVdbe); 326 } 327 db->pnBytesFreed = 0; 328 329 *pHighwater = 0; /* IMP: R-64479-57858 */ 330 *pCurrent = nByte; 331 332 break; 333 } 334 335 /* 336 ** Set *pCurrent to the total cache hits or misses encountered by all 337 ** pagers the database handle is connected to. *pHighwater is always set 338 ** to zero. 339 */ 340 case SQLITE_DBSTATUS_CACHE_SPILL: 341 op = SQLITE_DBSTATUS_CACHE_WRITE+1; 342 /* Fall through into the next case */ 343 case SQLITE_DBSTATUS_CACHE_HIT: 344 case SQLITE_DBSTATUS_CACHE_MISS: 345 case SQLITE_DBSTATUS_CACHE_WRITE:{ 346 int i; 347 int nRet = 0; 348 assert( SQLITE_DBSTATUS_CACHE_MISS==SQLITE_DBSTATUS_CACHE_HIT+1 ); 349 assert( SQLITE_DBSTATUS_CACHE_WRITE==SQLITE_DBSTATUS_CACHE_HIT+2 ); 350 351 for(i=0; i<db->nDb; i++){ 352 if( db->aDb[i].pBt ){ 353 Pager *pPager = sqlite3BtreePager(db->aDb[i].pBt); 354 sqlite3PagerCacheStat(pPager, op, resetFlag, &nRet); 355 } 356 } 357 *pHighwater = 0; /* IMP: R-42420-56072 */ 358 /* IMP: R-54100-20147 */ 359 /* IMP: R-29431-39229 */ 360 *pCurrent = nRet; 361 break; 362 } 363 364 /* Set *pCurrent to non-zero if there are unresolved deferred foreign 365 ** key constraints. Set *pCurrent to zero if all foreign key constraints 366 ** have been satisfied. The *pHighwater is always set to zero. 367 */ 368 case SQLITE_DBSTATUS_DEFERRED_FKS: { 369 *pHighwater = 0; /* IMP: R-11967-56545 */ 370 *pCurrent = db->nDeferredImmCons>0 || db->nDeferredCons>0; 371 break; 372 } 373 374 default: { 375 rc = SQLITE_ERROR; 376 } 377 } 378 sqlite3_mutex_leave(db->mutex); 379 return rc; 380 } 381