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Diffstat (limited to 'src/status.c')
| -rw-r--r-- | src/status.c | 398 |
1 files changed, 398 insertions, 0 deletions
diff --git a/src/status.c b/src/status.c new file mode 100644 index 0000000..7840167 --- /dev/null +++ b/src/status.c @@ -0,0 +1,398 @@ +/* +** 2008 June 18 +** +** The author disclaims copyright to this source code. In place of +** a legal notice, here is a blessing: +** +** May you do good and not evil. +** May you find forgiveness for yourself and forgive others. +** May you share freely, never taking more than you give. +** +************************************************************************* +** +** This module implements the sqlite3_status() interface and related +** functionality. +*/ +#include "sqliteInt.h" +#include "vdbeInt.h" + +/* +** Variables in which to record status information. +*/ +#if SQLITE_PTRSIZE>4 +typedef sqlite3_int64 sqlite3StatValueType; +#else +typedef u32 sqlite3StatValueType; +#endif +typedef struct sqlite3StatType sqlite3StatType; +static SQLITE_WSD struct sqlite3StatType { + sqlite3StatValueType nowValue[10]; /* Current value */ + sqlite3StatValueType mxValue[10]; /* Maximum value */ +} sqlite3Stat = { {0,}, {0,} }; + +/* +** Elements of sqlite3Stat[] are protected by either the memory allocator +** mutex, or by the pcache1 mutex. The following array determines which. +*/ +static const char statMutex[] = { + 0, /* SQLITE_STATUS_MEMORY_USED */ + 1, /* SQLITE_STATUS_PAGECACHE_USED */ + 1, /* SQLITE_STATUS_PAGECACHE_OVERFLOW */ + 0, /* SQLITE_STATUS_SCRATCH_USED */ + 0, /* SQLITE_STATUS_SCRATCH_OVERFLOW */ + 0, /* SQLITE_STATUS_MALLOC_SIZE */ + 0, /* SQLITE_STATUS_PARSER_STACK */ + 1, /* SQLITE_STATUS_PAGECACHE_SIZE */ + 0, /* SQLITE_STATUS_SCRATCH_SIZE */ + 0, /* SQLITE_STATUS_MALLOC_COUNT */ +}; + + +/* The "wsdStat" macro will resolve to the status information +** state vector. If writable static data is unsupported on the target, +** we have to locate the state vector at run-time. In the more common +** case where writable static data is supported, wsdStat can refer directly +** to the "sqlite3Stat" state vector declared above. +*/ +#ifdef SQLITE_OMIT_WSD +# define wsdStatInit sqlite3StatType *x = &GLOBAL(sqlite3StatType,sqlite3Stat) +# define wsdStat x[0] +#else +# define wsdStatInit +# define wsdStat sqlite3Stat +#endif + +/* +** Return the current value of a status parameter. The caller must +** be holding the appropriate mutex. +*/ +sqlite3_int64 sqlite3StatusValue(int op){ + wsdStatInit; + assert( op>=0 && op<ArraySize(wsdStat.nowValue) ); + assert( op>=0 && op<ArraySize(statMutex) ); + assert( sqlite3_mutex_held(statMutex[op] ? sqlite3Pcache1Mutex() + : sqlite3MallocMutex()) ); + return wsdStat.nowValue[op]; +} + +/* +** Add N to the value of a status record. The caller must hold the +** appropriate mutex. (Locking is checked by assert()). +** +** The StatusUp() routine can accept positive or negative values for N. +** The value of N is added to the current status value and the high-water +** mark is adjusted if necessary. +** +** The StatusDown() routine lowers the current value by N. The highwater +** mark is unchanged. N must be non-negative for StatusDown(). +*/ +void sqlite3StatusUp(int op, int N){ + wsdStatInit; + assert( op>=0 && op<ArraySize(wsdStat.nowValue) ); + assert( op>=0 && op<ArraySize(statMutex) ); + assert( sqlite3_mutex_held(statMutex[op] ? sqlite3Pcache1Mutex() + : sqlite3MallocMutex()) ); + wsdStat.nowValue[op] += N; + if( wsdStat.nowValue[op]>wsdStat.mxValue[op] ){ + wsdStat.mxValue[op] = wsdStat.nowValue[op]; + } +} +void sqlite3StatusDown(int op, int N){ + wsdStatInit; + assert( N>=0 ); + assert( op>=0 && op<ArraySize(statMutex) ); + assert( sqlite3_mutex_held(statMutex[op] ? sqlite3Pcache1Mutex() + : sqlite3MallocMutex()) ); + assert( op>=0 && op<ArraySize(wsdStat.nowValue) ); + wsdStat.nowValue[op] -= N; +} + +/* +** Adjust the highwater mark if necessary. +** The caller must hold the appropriate mutex. +*/ +void sqlite3StatusHighwater(int op, int X){ + sqlite3StatValueType newValue; + wsdStatInit; + assert( X>=0 ); + newValue = (sqlite3StatValueType)X; + assert( op>=0 && op<ArraySize(wsdStat.nowValue) ); + assert( op>=0 && op<ArraySize(statMutex) ); + assert( sqlite3_mutex_held(statMutex[op] ? sqlite3Pcache1Mutex() + : sqlite3MallocMutex()) ); + assert( op==SQLITE_STATUS_MALLOC_SIZE + || op==SQLITE_STATUS_PAGECACHE_SIZE + || op==SQLITE_STATUS_PARSER_STACK ); + if( newValue>wsdStat.mxValue[op] ){ + wsdStat.mxValue[op] = newValue; + } +} + +/* +** Query status information. +*/ +int sqlite3_status64( + int op, + sqlite3_int64 *pCurrent, + sqlite3_int64 *pHighwater, + int resetFlag +){ + sqlite3_mutex *pMutex; + wsdStatInit; + if( op<0 || op>=ArraySize(wsdStat.nowValue) ){ + return SQLITE_MISUSE_BKPT; + } +#ifdef SQLITE_ENABLE_API_ARMOR + if( pCurrent==0 || pHighwater==0 ) return SQLITE_MISUSE_BKPT; +#endif + pMutex = statMutex[op] ? sqlite3Pcache1Mutex() : sqlite3MallocMutex(); + sqlite3_mutex_enter(pMutex); + *pCurrent = wsdStat.nowValue[op]; + *pHighwater = wsdStat.mxValue[op]; + if( resetFlag ){ + wsdStat.mxValue[op] = wsdStat.nowValue[op]; + } + sqlite3_mutex_leave(pMutex); + (void)pMutex; /* Prevent warning when SQLITE_THREADSAFE=0 */ + return SQLITE_OK; +} +int sqlite3_status(int op, int *pCurrent, int *pHighwater, int resetFlag){ + sqlite3_int64 iCur = 0, iHwtr = 0; + int rc; +#ifdef SQLITE_ENABLE_API_ARMOR + if( pCurrent==0 || pHighwater==0 ) return SQLITE_MISUSE_BKPT; +#endif + rc = sqlite3_status64(op, &iCur, &iHwtr, resetFlag); + if( rc==0 ){ + *pCurrent = (int)iCur; + *pHighwater = (int)iHwtr; + } + return rc; +} + +/* +** Return the number of LookasideSlot elements on the linked list +*/ +static u32 countLookasideSlots(LookasideSlot *p){ + u32 cnt = 0; + while( p ){ + p = p->pNext; + cnt++; + } + return cnt; +} + +/* +** Count the number of slots of lookaside memory that are outstanding +*/ +int sqlite3LookasideUsed(sqlite3 *db, int *pHighwater){ + u32 nInit = countLookasideSlots(db->lookaside.pInit); + u32 nFree = countLookasideSlots(db->lookaside.pFree); +#ifndef SQLITE_OMIT_TWOSIZE_LOOKASIDE + nInit += countLookasideSlots(db->lookaside.pSmallInit); + nFree += countLookasideSlots(db->lookaside.pSmallFree); +#endif /* SQLITE_OMIT_TWOSIZE_LOOKASIDE */ + if( pHighwater ) *pHighwater = db->lookaside.nSlot - nInit; + return db->lookaside.nSlot - (nInit+nFree); +} + +/* +** Query status information for a single database connection +*/ +int sqlite3_db_status( + sqlite3 *db, /* The database connection whose status is desired */ + int op, /* Status verb */ + int *pCurrent, /* Write current value here */ + int *pHighwater, /* Write high-water mark here */ + int resetFlag /* Reset high-water mark if true */ +){ + int rc = SQLITE_OK; /* Return code */ +#ifdef SQLITE_ENABLE_API_ARMOR + if( !sqlite3SafetyCheckOk(db) || pCurrent==0|| pHighwater==0 ){ + return SQLITE_MISUSE_BKPT; + } +#endif + sqlite3_mutex_enter(db->mutex); + switch( op ){ + case SQLITE_DBSTATUS_LOOKASIDE_USED: { + *pCurrent = sqlite3LookasideUsed(db, pHighwater); + if( resetFlag ){ + LookasideSlot *p = db->lookaside.pFree; + if( p ){ + while( p->pNext ) p = p->pNext; + p->pNext = db->lookaside.pInit; + db->lookaside.pInit = db->lookaside.pFree; + db->lookaside.pFree = 0; + } +#ifndef SQLITE_OMIT_TWOSIZE_LOOKASIDE + p = db->lookaside.pSmallFree; + if( p ){ + while( p->pNext ) p = p->pNext; + p->pNext = db->lookaside.pSmallInit; + db->lookaside.pSmallInit = db->lookaside.pSmallFree; + db->lookaside.pSmallFree = 0; + } +#endif + } + break; + } + + case SQLITE_DBSTATUS_LOOKASIDE_HIT: + case SQLITE_DBSTATUS_LOOKASIDE_MISS_SIZE: + case SQLITE_DBSTATUS_LOOKASIDE_MISS_FULL: { + testcase( op==SQLITE_DBSTATUS_LOOKASIDE_HIT ); + testcase( op==SQLITE_DBSTATUS_LOOKASIDE_MISS_SIZE ); + testcase( op==SQLITE_DBSTATUS_LOOKASIDE_MISS_FULL ); + assert( (op-SQLITE_DBSTATUS_LOOKASIDE_HIT)>=0 ); + assert( (op-SQLITE_DBSTATUS_LOOKASIDE_HIT)<3 ); + *pCurrent = 0; + *pHighwater = db->lookaside.anStat[op - SQLITE_DBSTATUS_LOOKASIDE_HIT]; + if( resetFlag ){ + db->lookaside.anStat[op - SQLITE_DBSTATUS_LOOKASIDE_HIT] = 0; + } + break; + } + + /* + ** Return an approximation for the amount of memory currently used + ** by all pagers associated with the given database connection. The + ** highwater mark is meaningless and is returned as zero. + */ + case SQLITE_DBSTATUS_CACHE_USED_SHARED: + case SQLITE_DBSTATUS_CACHE_USED: { + int totalUsed = 0; + int i; + sqlite3BtreeEnterAll(db); + for(i=0; i<db->nDb; i++){ + Btree *pBt = db->aDb[i].pBt; + if( pBt ){ + Pager *pPager = sqlite3BtreePager(pBt); + int nByte = sqlite3PagerMemUsed(pPager); + if( op==SQLITE_DBSTATUS_CACHE_USED_SHARED ){ + nByte = nByte / sqlite3BtreeConnectionCount(pBt); + } + totalUsed += nByte; + } + } + sqlite3BtreeLeaveAll(db); + *pCurrent = totalUsed; + *pHighwater = 0; + break; + } + + /* + ** *pCurrent gets an accurate estimate of the amount of memory used + ** to store the schema for all databases (main, temp, and any ATTACHed + ** databases. *pHighwater is set to zero. + */ + case SQLITE_DBSTATUS_SCHEMA_USED: { + int i; /* Used to iterate through schemas */ + int nByte = 0; /* Used to accumulate return value */ + + 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) ){ + HashElem *p; + + nByte += sqlite3GlobalConfig.m.xRoundup(sizeof(HashElem)) * ( + pSchema->tblHash.count + + pSchema->trigHash.count + + pSchema->idxHash.count + + pSchema->fkeyHash.count + ); + nByte += sqlite3_msize(pSchema->tblHash.ht); + nByte += sqlite3_msize(pSchema->trigHash.ht); + nByte += sqlite3_msize(pSchema->idxHash.ht); + nByte += sqlite3_msize(pSchema->fkeyHash.ht); + + for(p=sqliteHashFirst(&pSchema->trigHash); p; p=sqliteHashNext(p)){ + sqlite3DeleteTrigger(db, (Trigger*)sqliteHashData(p)); + } + for(p=sqliteHashFirst(&pSchema->tblHash); p; p=sqliteHashNext(p)){ + sqlite3DeleteTable(db, (Table *)sqliteHashData(p)); + } + } + } + db->pnBytesFreed = 0; + db->lookaside.pEnd = db->lookaside.pTrueEnd; + sqlite3BtreeLeaveAll(db); + + *pHighwater = 0; + *pCurrent = nByte; + break; + } + + /* + ** *pCurrent gets an accurate estimate of the amount of memory used + ** to store all prepared statements. + ** *pHighwater is set to zero. + */ + case SQLITE_DBSTATUS_STMT_USED: { + struct Vdbe *pVdbe; /* Used to iterate through VMs */ + 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->pVNext){ + sqlite3VdbeDelete(pVdbe); + } + db->lookaside.pEnd = db->lookaside.pTrueEnd; + db->pnBytesFreed = 0; + + *pHighwater = 0; /* IMP: R-64479-57858 */ + *pCurrent = nByte; + + break; + } + + /* + ** Set *pCurrent to the total cache hits or misses encountered by all + ** pagers the database handle is connected to. *pHighwater is always set + ** to zero. + */ + case SQLITE_DBSTATUS_CACHE_SPILL: + op = SQLITE_DBSTATUS_CACHE_WRITE+1; + /* no break */ deliberate_fall_through + case SQLITE_DBSTATUS_CACHE_HIT: + case SQLITE_DBSTATUS_CACHE_MISS: + case SQLITE_DBSTATUS_CACHE_WRITE:{ + int i; + int nRet = 0; + assert( SQLITE_DBSTATUS_CACHE_MISS==SQLITE_DBSTATUS_CACHE_HIT+1 ); + assert( SQLITE_DBSTATUS_CACHE_WRITE==SQLITE_DBSTATUS_CACHE_HIT+2 ); + + for(i=0; i<db->nDb; i++){ + if( db->aDb[i].pBt ){ + Pager *pPager = sqlite3BtreePager(db->aDb[i].pBt); + sqlite3PagerCacheStat(pPager, op, resetFlag, &nRet); + } + } + *pHighwater = 0; /* IMP: R-42420-56072 */ + /* IMP: R-54100-20147 */ + /* IMP: R-29431-39229 */ + *pCurrent = nRet; + break; + } + + /* Set *pCurrent to non-zero if there are unresolved deferred foreign + ** key constraints. Set *pCurrent to zero if all foreign key constraints + ** have been satisfied. The *pHighwater is always set to zero. + */ + case SQLITE_DBSTATUS_DEFERRED_FKS: { + *pHighwater = 0; /* IMP: R-11967-56545 */ + *pCurrent = db->nDeferredImmCons>0 || db->nDeferredCons>0; + break; + } + + default: { + rc = SQLITE_ERROR; + } + } + sqlite3_mutex_leave(db->mutex); + return rc; +} |