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Overview
Comment: | Speed up xAccess() calls made on an RBU VFS when there are lots of open connections. |
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Downloads: | Tarball | ZIP archive |
Timelines: | family | ancestors | descendants | both | trunk |
Files: | files | file ages | folders |
SHA3-256: |
310b4b65b8c8ee080760c7efb4c7e202 |
User & Date: | dan 2018-10-01 17:33:35.846 |
References
2018-10-25
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11:55 | Speed up xAccess() calls made on an RBU VFS when there are lots of open connections. Cherrypick of [310b4b65]. (check-in: fda8fdb0cb user: dan tags: branch-3.22) | |
Context
2018-10-25
| ||
11:55 | Speed up xAccess() calls made on an RBU VFS when there are lots of open connections. Cherrypick of [310b4b65]. (check-in: fda8fdb0cb user: dan tags: branch-3.22) | |
2018-10-01
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21:41 | Add the "PRAGMA table_xinfo" command that works like table_info but also shows hidden columns in virtual tables and adds the "hidden" boolean column. (check-in: defa0515b8 user: drh tags: trunk) | |
17:33 | Speed up xAccess() calls made on an RBU VFS when there are lots of open connections. (check-in: 310b4b65b8 user: dan tags: trunk) | |
13:54 | Fix a potential crash that can occur while reading an index from a corrupt database file. The corruption is a record-header-size that is larger than 0x7fffffff. Problem detected by OSSFuzz against GDAL and reported to us (with a suggested fix) by Even Rouault. The test case is in TH3. (check-in: 8ac2cdda68 user: drh tags: trunk) | |
Changes
Changes to ext/rbu/sqlite3rbu.c.
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401 402 403 404 405 406 407 | ** space used by the RBU handle. */ struct rbu_vfs { sqlite3_vfs base; /* rbu VFS shim methods */ sqlite3_vfs *pRealVfs; /* Underlying VFS */ sqlite3_mutex *mutex; /* Mutex to protect pMain */ sqlite3rbu *pRbu; /* Owner RBU object */ | | > | 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 | ** space used by the RBU handle. */ struct rbu_vfs { sqlite3_vfs base; /* rbu VFS shim methods */ sqlite3_vfs *pRealVfs; /* Underlying VFS */ sqlite3_mutex *mutex; /* Mutex to protect pMain */ sqlite3rbu *pRbu; /* Owner RBU object */ rbu_file *pMain; /* List of main db files */ rbu_file *pMainRbu; /* List of main db files with pRbu!=0 */ }; /* ** Each file opened by an rbu VFS is represented by an instance of ** the following structure. ** ** If this is a temporary file (pRbu!=0 && flags&DELETE_ON_CLOSE), variable |
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430 431 432 433 434 435 436 437 438 439 440 441 442 443 | int nShm; /* Number of entries in apShm[] array */ char **apShm; /* Array of mmap'd *-shm regions */ char *zDel; /* Delete this when closing file */ const char *zWal; /* Wal filename for this main db file */ rbu_file *pWalFd; /* Wal file descriptor for this main db */ rbu_file *pMainNext; /* Next MAIN_DB file */ }; /* ** True for an RBU vacuum handle, or false otherwise. */ #define rbuIsVacuum(p) ((p)->zTarget==0) | > | 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 | int nShm; /* Number of entries in apShm[] array */ char **apShm; /* Array of mmap'd *-shm regions */ char *zDel; /* Delete this when closing file */ const char *zWal; /* Wal filename for this main db file */ rbu_file *pWalFd; /* Wal file descriptor for this main db */ rbu_file *pMainNext; /* Next MAIN_DB file */ rbu_file *pMainRbuNext; /* Next MAIN_DB file with pRbu!=0 */ }; /* ** True for an RBU vacuum handle, or false otherwise. */ #define rbuIsVacuum(p) ((p)->zTarget==0) |
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4025 4026 4027 4028 4029 4030 4031 4032 4033 4034 4035 4036 4037 4038 4039 4040 4041 4042 4043 4044 4045 4046 4047 4048 4049 | i64 nDiff = nNew - pFd->sz; pRbu->szTemp += nDiff; pFd->sz = nNew; assert( pRbu->szTemp>=0 ); if( pRbu->szTempLimit && pRbu->szTemp>pRbu->szTempLimit ) return SQLITE_FULL; return SQLITE_OK; } /* ** Close an rbu file. */ static int rbuVfsClose(sqlite3_file *pFile){ rbu_file *p = (rbu_file*)pFile; int rc; int i; /* Free the contents of the apShm[] array. And the array itself. */ for(i=0; i<p->nShm; i++){ sqlite3_free(p->apShm[i]); } sqlite3_free(p->apShm); p->apShm = 0; sqlite3_free(p->zDel); if( p->openFlags & SQLITE_OPEN_MAIN_DB ){ | > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > < < < | < > | 4027 4028 4029 4030 4031 4032 4033 4034 4035 4036 4037 4038 4039 4040 4041 4042 4043 4044 4045 4046 4047 4048 4049 4050 4051 4052 4053 4054 4055 4056 4057 4058 4059 4060 4061 4062 4063 4064 4065 4066 4067 4068 4069 4070 4071 4072 4073 4074 4075 4076 4077 4078 4079 4080 4081 4082 4083 4084 4085 4086 4087 4088 4089 4090 4091 4092 4093 4094 4095 4096 4097 4098 4099 4100 4101 4102 4103 4104 4105 4106 4107 4108 4109 4110 4111 4112 4113 4114 4115 4116 4117 4118 4119 4120 4121 4122 4123 4124 4125 4126 4127 4128 4129 | i64 nDiff = nNew - pFd->sz; pRbu->szTemp += nDiff; pFd->sz = nNew; assert( pRbu->szTemp>=0 ); if( pRbu->szTempLimit && pRbu->szTemp>pRbu->szTempLimit ) return SQLITE_FULL; return SQLITE_OK; } /* ** Add an item to the main-db lists, if it is not already present. ** ** There are two main-db lists. One for all file descriptors, and one ** for all file descriptors with rbu_file.pDb!=0. If the argument has ** rbu_file.pDb!=0, then it is assumed to already be present on the ** main list and is only added to the pDb!=0 list. */ static void rbuMainlistAdd(rbu_file *p){ rbu_vfs *pRbuVfs = p->pRbuVfs; rbu_file *pIter; assert( (p->openFlags & SQLITE_OPEN_MAIN_DB) ); sqlite3_mutex_enter(pRbuVfs->mutex); if( p->pRbu==0 ){ for(pIter=pRbuVfs->pMain; pIter; pIter=pIter->pMainNext); p->pMainNext = pRbuVfs->pMain; pRbuVfs->pMain = p; }else{ for(pIter=pRbuVfs->pMainRbu; pIter && pIter!=p; pIter=pIter->pMainRbuNext){} if( pIter==0 ){ p->pMainRbuNext = pRbuVfs->pMainRbu; pRbuVfs->pMainRbu = p; } } sqlite3_mutex_leave(pRbuVfs->mutex); } /* ** Remove an item from the main-db lists. */ static void rbuMainlistRemove(rbu_file *p){ rbu_file **pp; sqlite3_mutex_enter(p->pRbuVfs->mutex); for(pp=&p->pRbuVfs->pMain; *pp && *pp!=p; pp=&((*pp)->pMainNext)){} if( *pp ) *pp = p->pMainNext; p->pMainNext = 0; for(pp=&p->pRbuVfs->pMainRbu; *pp && *pp!=p; pp=&((*pp)->pMainRbuNext)){} if( *pp ) *pp = p->pMainRbuNext; p->pMainRbuNext = 0; sqlite3_mutex_leave(p->pRbuVfs->mutex); } /* ** Given that zWal points to a buffer containing a wal file name passed to ** either the xOpen() or xAccess() VFS method, search the main-db list for ** a file-handle opened by the same database connection on the corresponding ** database file. ** ** If parameter bRbu is true, only search for file-descriptors with ** rbu_file.pDb!=0. */ static rbu_file *rbuFindMaindb(rbu_vfs *pRbuVfs, const char *zWal, int bRbu){ rbu_file *pDb; sqlite3_mutex_enter(pRbuVfs->mutex); if( bRbu ){ for(pDb=pRbuVfs->pMainRbu; pDb && pDb->zWal!=zWal; pDb=pDb->pMainRbuNext){} }else{ for(pDb=pRbuVfs->pMain; pDb && pDb->zWal!=zWal; pDb=pDb->pMainNext){} } sqlite3_mutex_leave(pRbuVfs->mutex); return pDb; } /* ** Close an rbu file. */ static int rbuVfsClose(sqlite3_file *pFile){ rbu_file *p = (rbu_file*)pFile; int rc; int i; /* Free the contents of the apShm[] array. And the array itself. */ for(i=0; i<p->nShm; i++){ sqlite3_free(p->apShm[i]); } sqlite3_free(p->apShm); p->apShm = 0; sqlite3_free(p->zDel); if( p->openFlags & SQLITE_OPEN_MAIN_DB ){ rbuMainlistRemove(p); rbuUnlockShm(p); p->pReal->pMethods->xShmUnmap(p->pReal, 0); } else if( (p->openFlags & SQLITE_OPEN_DELETEONCLOSE) && p->pRbu ){ rbuUpdateTempSize(p, 0); } assert( p->pMainNext==0 && p->pRbuVfs->pMain!=p ); /* Close the underlying file handle */ rc = p->pReal->pMethods->xClose(p->pReal); return rc; } |
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4312 4313 4314 4315 4316 4317 4318 4319 4320 4321 4322 4323 4324 4325 | rc = xControl(p->pReal, SQLITE_FCNTL_ZIPVFS, &dummy); if( rc==SQLITE_OK ){ rc = SQLITE_ERROR; pRbu->zErrmsg = sqlite3_mprintf("rbu/zipvfs setup error"); }else if( rc==SQLITE_NOTFOUND ){ pRbu->pTargetFd = p; p->pRbu = pRbu; if( p->pWalFd ) p->pWalFd->pRbu = pRbu; rc = SQLITE_OK; } } return rc; } else if( op==SQLITE_FCNTL_RBUCNT ){ | > > > | 4374 4375 4376 4377 4378 4379 4380 4381 4382 4383 4384 4385 4386 4387 4388 4389 4390 | rc = xControl(p->pReal, SQLITE_FCNTL_ZIPVFS, &dummy); if( rc==SQLITE_OK ){ rc = SQLITE_ERROR; pRbu->zErrmsg = sqlite3_mprintf("rbu/zipvfs setup error"); }else if( rc==SQLITE_NOTFOUND ){ pRbu->pTargetFd = p; p->pRbu = pRbu; if( p->openFlags & SQLITE_OPEN_MAIN_DB ){ rbuMainlistAdd(p); } if( p->pWalFd ) p->pWalFd->pRbu = pRbu; rc = SQLITE_OK; } } return rc; } else if( op==SQLITE_FCNTL_RBUCNT ){ |
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4473 4474 4475 4476 4477 4478 4479 | /* Release the checkpointer and writer locks */ rbuUnlockShm(p); rc = p->pReal->pMethods->xShmUnmap(p->pReal, delFlag); } return rc; } | < < < < < < < < < < < < < < | 4538 4539 4540 4541 4542 4543 4544 4545 4546 4547 4548 4549 4550 4551 | /* Release the checkpointer and writer locks */ rbuUnlockShm(p); rc = p->pReal->pMethods->xShmUnmap(p->pReal, delFlag); } return rc; } /* ** A main database named zName has just been opened. The following ** function returns a pointer to a buffer owned by SQLite that contains ** the name of the *-wal file this db connection will use. SQLite ** happens to pass a pointer to this buffer when using xAccess() ** or xOpen() to operate on the *-wal file. */ |
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4565 4566 4567 4568 4569 4570 4571 | ** (pFd->zWal) to point to a buffer owned by SQLite that contains ** the name of the *-wal file this db connection will use. SQLite ** happens to pass a pointer to this buffer when using xAccess() ** or xOpen() to operate on the *-wal file. */ pFd->zWal = rbuMainToWal(zName, flags); } else if( flags & SQLITE_OPEN_WAL ){ | | | 4616 4617 4618 4619 4620 4621 4622 4623 4624 4625 4626 4627 4628 4629 4630 | ** (pFd->zWal) to point to a buffer owned by SQLite that contains ** the name of the *-wal file this db connection will use. SQLite ** happens to pass a pointer to this buffer when using xAccess() ** or xOpen() to operate on the *-wal file. */ pFd->zWal = rbuMainToWal(zName, flags); } else if( flags & SQLITE_OPEN_WAL ){ rbu_file *pDb = rbuFindMaindb(pRbuVfs, zName, 0); if( pDb ){ if( pDb->pRbu && pDb->pRbu->eStage==RBU_STAGE_OAL ){ /* This call is to open a *-wal file. Intead, open the *-oal. This ** code ensures that the string passed to xOpen() is terminated by a ** pair of '\0' bytes in case the VFS attempts to extract a URI ** parameter from it. */ const char *zBase = zName; |
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4617 4618 4619 4620 4621 4622 4623 | } if( pFd->pReal->pMethods ){ /* The xOpen() operation has succeeded. Set the sqlite3_file.pMethods ** pointer and, if the file is a main database file, link it into the ** mutex protected linked list of all such files. */ pFile->pMethods = &rbuvfs_io_methods; if( flags & SQLITE_OPEN_MAIN_DB ){ | < < | < | 4668 4669 4670 4671 4672 4673 4674 4675 4676 4677 4678 4679 4680 4681 4682 | } if( pFd->pReal->pMethods ){ /* The xOpen() operation has succeeded. Set the sqlite3_file.pMethods ** pointer and, if the file is a main database file, link it into the ** mutex protected linked list of all such files. */ pFile->pMethods = &rbuvfs_io_methods; if( flags & SQLITE_OPEN_MAIN_DB ){ rbuMainlistAdd(pFd); } }else{ sqlite3_free(pFd->zDel); } return rc; } |
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4668 4669 4670 4671 4672 4673 4674 | ** ** b) if the *-wal file does not exist, claim that it does anyway, ** causing SQLite to call xOpen() to open it. This call will also ** be intercepted (see the rbuVfsOpen() function) and the *-oal ** file opened instead. */ if( rc==SQLITE_OK && flags==SQLITE_ACCESS_EXISTS ){ | | | 4716 4717 4718 4719 4720 4721 4722 4723 4724 4725 4726 4727 4728 4729 4730 | ** ** b) if the *-wal file does not exist, claim that it does anyway, ** causing SQLite to call xOpen() to open it. This call will also ** be intercepted (see the rbuVfsOpen() function) and the *-oal ** file opened instead. */ if( rc==SQLITE_OK && flags==SQLITE_ACCESS_EXISTS ){ rbu_file *pDb = rbuFindMaindb(pRbuVfs, zPath, 1); if( pDb && pDb->pRbu && pDb->pRbu->eStage==RBU_STAGE_OAL ){ if( *pResOut ){ rc = SQLITE_CANTOPEN; }else{ sqlite3_int64 sz = 0; rc = rbuVfsFileSize(&pDb->base, &sz); *pResOut = (sz>0); |
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