database/sqlite
1
0
Fork 0
mirror of https://github.com/sqlite/sqlite.git synced 2025-08-07 02:42:48 +03:00
Code Activity

Modify the interface to the blocking wal-checkpoint functionality.

Browse Source 
FossilOrigin-Name: 72787c010c8944e8fcf9c98aa4482f129142d8e9
This commit is contained in:
dan
2010-11-18 12:11:05 +00:00
parent a58f26f93f
commit cdc1f049bf
14 changed files with 236 additions and 93 deletions
Download Patch File Download Diff File Expand all files Collapse all files

48
src/wal.c
View File

@@ -1576,11 +1576,13 @@ static int walBusyLock(
*/
static int walCheckpoint(
Wal *pWal, /* Wal connection */
int eMode, /* One of PASSIVE, FULL or RESTART */
int (*xBusy)(void*), /* Function to call when busy */
void *pBusyArg, /* Context argument for xBusyHandler */
int sync_flags, /* Flags for OsSync() (or 0) */
int nBuf, /* Size of zBuf in bytes */
u8 *zBuf /* Temporary buffer to use */
u8 *zBuf, /* Temporary buffer to use */
int *pnCkpt /* Total frames checkpointed */
){
int rc; /* Return code */
int szPage; /* Database page-size */
@@ -1610,6 +1612,10 @@ static int walCheckpoint(
goto walcheckpoint_out;
}
pInfo = walCkptInfo(pWal);
mxPage = pWal->hdr.nPage;
if( pnCkpt ) *pnCkpt = pInfo->nBackfill;
/* Compute in mxSafeFrame the index of the last frame of the WAL that is
** safe to write into the database. Frames beyond mxSafeFrame might
** overwrite database pages that are in use by active readers and thus
@@ -1617,8 +1623,6 @@ static int walCheckpoint(
*/
do {
mxSafeFrame = pWal->hdr.mxFrame;
mxPage = pWal->hdr.nPage;
pInfo = walCkptInfo(pWal);
for(i=1; i<WAL_NREADER; i++){
u32 y = pInfo->aReadMark[i];
if( mxSafeFrame>=y ){
@@ -1634,7 +1638,8 @@ static int walCheckpoint(
}
}
}
}while( xBusy && mxSafeFrame<pWal->hdr.mxFrame && xBusy(pBusyArg) );
}while( eMode!=SQLITE_CHECKPOINT_PASSIVE
&& xBusy && mxSafeFrame<pWal->hdr.mxFrame && xBusy(pBusyArg) );
if( pInfo->nBackfill<mxSafeFrame
&& (rc = walBusyLock(pWal, xBusy, pBusyArg, WAL_READ_LOCK(0), 1))==SQLITE_OK
@@ -1685,19 +1690,12 @@ static int walCheckpoint(
}
if( rc==SQLITE_OK ){
pInfo->nBackfill = mxSafeFrame;
if( pnCkpt ) *pnCkpt = mxSafeFrame;
}
}
/* Release the reader lock held while backfilling */
walUnlockExclusive(pWal, WAL_READ_LOCK(0), 1);
if( xBusy && rc==SQLITE_OK && pWal->hdr.mxFrame==mxSafeFrame ){
assert( pWal->writeLock );
rc = walBusyLock(pWal, xBusy, pBusyArg, WAL_READ_LOCK(1), WAL_NREADER-1);
if( rc==SQLITE_OK ){
walUnlockExclusive(pWal, WAL_READ_LOCK(1), WAL_NREADER-1);
}
}
}
if( rc==SQLITE_BUSY ){
@@ -1706,6 +1704,17 @@ static int walCheckpoint(
rc = SQLITE_OK;
}
if( rc==SQLITE_OK
&& eMode==SQLITE_CHECKPOINT_RESTART
&& pWal->hdr.mxFrame==mxSafeFrame
){
assert( pWal->writeLock );
rc = walBusyLock(pWal, xBusy, pBusyArg, WAL_READ_LOCK(1), WAL_NREADER-1);
if( rc==SQLITE_OK ){
walUnlockExclusive(pWal, WAL_READ_LOCK(1), WAL_NREADER-1);
}
}
walcheckpoint_out:
walIteratorFree(pIter);
return rc;
@@ -1737,7 +1746,9 @@ int sqlite3WalClose(
if( pWal->exclusiveMode==WAL_NORMAL_MODE ){
pWal->exclusiveMode = WAL_EXCLUSIVE_MODE;
}
rc = sqlite3WalCheckpoint(pWal, 0, 0, sync_flags, nBuf, zBuf);
rc = sqlite3WalCheckpoint(
pWal, SQLITE_CHECKPOINT_PASSIVE, 0, 0, sync_flags, nBuf, zBuf, 0, 0
);
if( rc==SQLITE_OK ){
isDelete = 1;
}
@@ -2658,11 +2669,14 @@ int sqlite3WalFrames(
*/
int sqlite3WalCheckpoint(
Wal *pWal, /* Wal connection */
int eMode, /* PASSIVE, FULL or RESTART */
int (*xBusy)(void*), /* Function to call when busy */
void *pBusyArg, /* Context argument for xBusyHandler */
int sync_flags, /* Flags to sync db file with (or 0) */
int nBuf, /* Size of temporary buffer */
u8 *zBuf /* Temporary buffer to use */
u8 *zBuf, /* Temporary buffer to use */
int *pnLog, /* OUT: Number of frames in WAL */
int *pnCkpt /* OUT: Number of backfilled frames in WAL */
){
int rc; /* Return code */
int isChanged = 0; /* True if a new wal-index header is loaded */
@@ -2684,7 +2698,7 @@ int sqlite3WalCheckpoint(
** to prevent any writers from running while the checkpoint is underway.
** This has to be done before the call to walIndexReadHdr() below.
*/
if( xBusy ){
if( eMode!=SQLITE_CHECKPOINT_PASSIVE ){
rc = walBusyLock(pWal, xBusy, pBusyArg, WAL_WRITE_LOCK, 1);
if( rc==SQLITE_OK ) pWal->writeLock = 1;
}
@@ -2694,7 +2708,9 @@ int sqlite3WalCheckpoint(
rc = walIndexReadHdr(pWal, &isChanged);
}
if( rc==SQLITE_OK ){
rc = walCheckpoint(pWal, xBusy, pBusyArg, sync_flags, nBuf, zBuf);
if( pnLog ) *pnLog = (int)pWal->hdr.mxFrame;
rc = walCheckpoint(
pWal, eMode, xBusy, pBusyArg, sync_flags, nBuf, zBuf, pnCkpt);
}
if( isChanged ){
/* If a new wal-index header was loaded before the checkpoint was