4 ** The author disclaims copyright to this source code. In place of
5 ** a legal notice, here is a blessing:
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.
11 *************************************************************************
13 ** This module implements the sqlite3_status() interface and related
16 #include "sqliteInt.h"
20 ** Variables in which to record status information.
22 typedef struct sqlite3StatType sqlite3StatType;
23 static SQLITE_WSD struct sqlite3StatType {
24 int nowValue[10]; /* Current value */
25 int mxValue[10]; /* Maximum value */
26 } sqlite3Stat = { {0,}, {0,} };
29 /* The "wsdStat" macro will resolve to the status information
30 ** state vector. If writable static data is unsupported on the target,
31 ** we have to locate the state vector at run-time. In the more common
32 ** case where writable static data is supported, wsdStat can refer directly
33 ** to the "sqlite3Stat" state vector declared above.
35 #ifdef SQLITE_OMIT_WSD
36 # define wsdStatInit sqlite3StatType *x = &GLOBAL(sqlite3StatType,sqlite3Stat)
40 # define wsdStat sqlite3Stat
44 ** Return the current value of a status parameter.
46 int sqlite3StatusValue(int op){
48 assert( op>=0 && op<ArraySize(wsdStat.nowValue) );
49 return wsdStat.nowValue[op];
53 ** Add N to the value of a status record. It is assumed that the
54 ** caller holds appropriate locks.
56 void sqlite3StatusAdd(int op, int N){
58 assert( op>=0 && op<ArraySize(wsdStat.nowValue) );
59 wsdStat.nowValue[op] += N;
60 if( wsdStat.nowValue[op]>wsdStat.mxValue[op] ){
61 wsdStat.mxValue[op] = wsdStat.nowValue[op];
66 ** Set the value of a status to X.
68 void sqlite3StatusSet(int op, int X){
70 assert( op>=0 && op<ArraySize(wsdStat.nowValue) );
71 wsdStat.nowValue[op] = X;
72 if( wsdStat.nowValue[op]>wsdStat.mxValue[op] ){
73 wsdStat.mxValue[op] = wsdStat.nowValue[op];
78 ** Query status information.
80 ** This implementation assumes that reading or writing an aligned
81 ** 32-bit integer is an atomic operation. If that assumption is not true,
82 ** then this routine is not threadsafe.
84 int sqlite3_status(int op, int *pCurrent, int *pHighwater, int resetFlag){
86 if( op<0 || op>=ArraySize(wsdStat.nowValue) ){
87 return SQLITE_MISUSE_BKPT;
89 *pCurrent = wsdStat.nowValue[op];
90 *pHighwater = wsdStat.mxValue[op];
92 wsdStat.mxValue[op] = wsdStat.nowValue[op];
98 ** Query status information for a single database connection
100 int sqlite3_db_status(
101 sqlite3 *db, /* The database connection whose status is desired */
102 int op, /* Status verb */
103 int *pCurrent, /* Write current value here */
104 int *pHighwater, /* Write high-water mark here */
105 int resetFlag /* Reset high-water mark if true */
107 int rc = SQLITE_OK; /* Return code */
108 sqlite3_mutex_enter(db->mutex);
110 case SQLITE_DBSTATUS_LOOKASIDE_USED: {
111 *pCurrent = db->lookaside.nOut;
112 *pHighwater = db->lookaside.mxOut;
114 db->lookaside.mxOut = db->lookaside.nOut;
119 case SQLITE_DBSTATUS_LOOKASIDE_HIT:
120 case SQLITE_DBSTATUS_LOOKASIDE_MISS_SIZE:
121 case SQLITE_DBSTATUS_LOOKASIDE_MISS_FULL: {
122 testcase( op==SQLITE_DBSTATUS_LOOKASIDE_HIT );
123 testcase( op==SQLITE_DBSTATUS_LOOKASIDE_MISS_SIZE );
124 testcase( op==SQLITE_DBSTATUS_LOOKASIDE_MISS_FULL );
125 assert( (op-SQLITE_DBSTATUS_LOOKASIDE_HIT)>=0 );
126 assert( (op-SQLITE_DBSTATUS_LOOKASIDE_HIT)<3 );
128 *pHighwater = db->lookaside.anStat[op - SQLITE_DBSTATUS_LOOKASIDE_HIT];
130 db->lookaside.anStat[op - SQLITE_DBSTATUS_LOOKASIDE_HIT] = 0;
136 ** Return an approximation for the amount of memory currently used
137 ** by all pagers associated with the given database connection. The
138 ** highwater mark is meaningless and is returned as zero.
140 case SQLITE_DBSTATUS_CACHE_USED: {
143 sqlite3BtreeEnterAll(db);
144 for(i=0; i<db->nDb; i++){
145 Btree *pBt = db->aDb[i].pBt;
147 Pager *pPager = sqlite3BtreePager(pBt);
148 totalUsed += sqlite3PagerMemUsed(pPager);
151 sqlite3BtreeLeaveAll(db);
152 *pCurrent = totalUsed;
158 ** *pCurrent gets an accurate estimate of the amount of memory used
159 ** to store the schema for all databases (main, temp, and any ATTACHed
160 ** databases. *pHighwater is set to zero.
162 case SQLITE_DBSTATUS_SCHEMA_USED: {
163 int i; /* Used to iterate through schemas */
164 int nByte = 0; /* Used to accumulate return value */
166 sqlite3BtreeEnterAll(db);
167 db->pnBytesFreed = &nByte;
168 for(i=0; i<db->nDb; i++){
169 Schema *pSchema = db->aDb[i].pSchema;
170 if( ALWAYS(pSchema!=0) ){
173 nByte += sqlite3GlobalConfig.m.xRoundup(sizeof(HashElem)) * (
174 pSchema->tblHash.count
175 + pSchema->trigHash.count
176 + pSchema->idxHash.count
177 + pSchema->fkeyHash.count
179 nByte += sqlite3MallocSize(pSchema->tblHash.ht);
180 nByte += sqlite3MallocSize(pSchema->trigHash.ht);
181 nByte += sqlite3MallocSize(pSchema->idxHash.ht);
182 nByte += sqlite3MallocSize(pSchema->fkeyHash.ht);
184 for(p=sqliteHashFirst(&pSchema->trigHash); p; p=sqliteHashNext(p)){
185 sqlite3DeleteTrigger(db, (Trigger*)sqliteHashData(p));
187 for(p=sqliteHashFirst(&pSchema->tblHash); p; p=sqliteHashNext(p)){
188 sqlite3DeleteTable(db, (Table *)sqliteHashData(p));
192 db->pnBytesFreed = 0;
193 sqlite3BtreeLeaveAll(db);
201 ** *pCurrent gets an accurate estimate of the amount of memory used
202 ** to store all prepared statements.
203 ** *pHighwater is set to zero.
205 case SQLITE_DBSTATUS_STMT_USED: {
206 struct Vdbe *pVdbe; /* Used to iterate through VMs */
207 int nByte = 0; /* Used to accumulate return value */
209 db->pnBytesFreed = &nByte;
210 for(pVdbe=db->pVdbe; pVdbe; pVdbe=pVdbe->pNext){
211 sqlite3VdbeDeleteObject(db, pVdbe);
213 db->pnBytesFreed = 0;
225 sqlite3_mutex_leave(db->mutex);