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Overview
Comment: | Changes to allow read-only clients to safely work with live databases. |
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Downloads: | Tarball | ZIP archive |
Timelines: | family | ancestors | descendants | both | read-only-clients |
Files: | files | file ages | folders |
SHA1: |
08cc3604cf95dcedd627605701959421 |
User & Date: | dan 2013-02-19 19:35:33.559 |
Context
2013-02-19
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20:16 | Add a test case for a read-only transaction outlasting an entire read-write session. And a fix. check-in: 3f53258219 user: dan tags: read-only-clients | |
19:35 | Changes to allow read-only clients to safely work with live databases. check-in: 08cc3604cf user: dan tags: read-only-clients | |
2013-02-18
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19:46 | Add support for read-only clients reading from dormant databases using the checkpointer lock. check-in: 45e4472618 user: dan tags: read-only-clients | |
Changes
Changes to lsm-test/lsmtest_tdb3.c.
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344 345 346 347 348 349 350 351 352 353 354 355 356 357 | lsm_env *pRealEnv = tdb_lsm_env(); if( iLock==2 && eType==LSM_LOCK_EXCL && p->pDb->bNoRecovery ){ return LSM_BUSY; } return pRealEnv->xLock(p->pReal, iLock, eType); } static int testEnvShmMap(lsm_file *pFile, int iRegion, int sz, void **pp){ LsmFile *p = (LsmFile *)pFile; lsm_env *pRealEnv = tdb_lsm_env(); return pRealEnv->xShmMap(p->pReal, iRegion, sz, pp); } | > > > > > > > > > > | 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 | lsm_env *pRealEnv = tdb_lsm_env(); if( iLock==2 && eType==LSM_LOCK_EXCL && p->pDb->bNoRecovery ){ return LSM_BUSY; } return pRealEnv->xLock(p->pReal, iLock, eType); } static int testEnvTestLock(lsm_file *pFile, int iLock, int nLock, int eType){ LsmFile *p = (LsmFile *)pFile; lsm_env *pRealEnv = tdb_lsm_env(); if( iLock==2 && eType==LSM_LOCK_EXCL && p->pDb->bNoRecovery ){ return LSM_BUSY; } return pRealEnv->xTestLock(p->pReal, iLock, nLock, eType); } static int testEnvShmMap(lsm_file *pFile, int iRegion, int sz, void **pp){ LsmFile *p = (LsmFile *)pFile; lsm_env *pRealEnv = tdb_lsm_env(); return pRealEnv->xShmMap(p->pReal, iRegion, sz, pp); } |
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935 936 937 938 939 940 941 942 943 944 945 946 947 948 | pDb->env.xSync = testEnvSync; pDb->env.xSectorSize = testEnvSectorSize; pDb->env.xRemap = testEnvRemap; pDb->env.xFileid = testEnvFileid; pDb->env.xClose = testEnvClose; pDb->env.xUnlink = testEnvUnlink; pDb->env.xLock = testEnvLock; pDb->env.xShmBarrier = testEnvShmBarrier; pDb->env.xShmMap = testEnvShmMap; pDb->env.xShmUnmap = testEnvShmUnmap; pDb->env.xSleep = testEnvSleep; rc = lsm_new(&pDb->env, &pDb->db); if( rc==LSM_OK ){ | > | 945 946 947 948 949 950 951 952 953 954 955 956 957 958 959 | pDb->env.xSync = testEnvSync; pDb->env.xSectorSize = testEnvSectorSize; pDb->env.xRemap = testEnvRemap; pDb->env.xFileid = testEnvFileid; pDb->env.xClose = testEnvClose; pDb->env.xUnlink = testEnvUnlink; pDb->env.xLock = testEnvLock; pDb->env.xTestLock = testEnvTestLock; pDb->env.xShmBarrier = testEnvShmBarrier; pDb->env.xShmMap = testEnvShmMap; pDb->env.xShmUnmap = testEnvShmUnmap; pDb->env.xSleep = testEnvSleep; rc = lsm_new(&pDb->env, &pDb->db); if( rc==LSM_OK ){ |
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Changes to src/lsm.h.
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60 61 62 63 64 65 66 67 68 69 70 71 72 73 | int (*xSync)(lsm_file *); int (*xSectorSize)(lsm_file *); int (*xRemap)(lsm_file *, lsm_i64, void **, lsm_i64*); int (*xFileid)(lsm_file *, void *pBuf, int *pnBuf); int (*xClose)(lsm_file *); int (*xUnlink)(lsm_env*, const char *); int (*xLock)(lsm_file*, int, int); int (*xShmMap)(lsm_file*, int, int, void **); void (*xShmBarrier)(void); int (*xShmUnmap)(lsm_file*, int); /****** memory allocation ****************************************/ void *pMemCtx; void *(*xMalloc)(lsm_env*, int); /* malloc(3) function */ void *(*xRealloc)(lsm_env*, void *, int); /* realloc(3) function */ | > | 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 | int (*xSync)(lsm_file *); int (*xSectorSize)(lsm_file *); int (*xRemap)(lsm_file *, lsm_i64, void **, lsm_i64*); int (*xFileid)(lsm_file *, void *pBuf, int *pnBuf); int (*xClose)(lsm_file *); int (*xUnlink)(lsm_env*, const char *); int (*xLock)(lsm_file*, int, int); int (*xTestLock)(lsm_file*, int, int, int); int (*xShmMap)(lsm_file*, int, int, void **); void (*xShmBarrier)(void); int (*xShmUnmap)(lsm_file*, int); /****** memory allocation ****************************************/ void *pMemCtx; void *(*xMalloc)(lsm_env*, int); /* malloc(3) function */ void *(*xRealloc)(lsm_env*, void *, int); /* realloc(3) function */ |
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Changes to src/lsmInt.h.
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133 134 135 136 137 138 139 | /* The number of available read locks. */ #define LSM_LOCK_NREADER 6 /* The number of available read-write client locks. */ #define LSM_LOCK_NRWCLIENT 16 /* Lock definitions. */ | | | > | | | | 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 | /* The number of available read locks. */ #define LSM_LOCK_NREADER 6 /* The number of available read-write client locks. */ #define LSM_LOCK_NRWCLIENT 16 /* Lock definitions. */ #define LSM_LOCK_DMS1 1 /* Serialize connect/disconnect ops */ #define LSM_LOCK_DMS2 2 /* Read-write connections */ #define LSM_LOCK_DMS3 3 /* Read-only connections */ #define LSM_LOCK_WRITER 4 #define LSM_LOCK_WORKER 5 #define LSM_LOCK_CHECKPOINTER 6 #define LSM_LOCK_READER(i) ((i) + LSM_LOCK_CHECKPOINTER + 1) #define LSM_LOCK_RWCLIENT(i) ((i) + LSM_LOCK_READER(LSM_LOCK_NREADER)) /* ** Hard limit on the number of free-list entries that may be stored in ** a checkpoint (the remainder are stored as a system record in the LSM). ** See also LSM_CONFIG_MAX_FREELIST. |
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552 553 554 555 556 557 558 | u32 nWrite; /* Total number of pages written to disk */ }; #define LSM_INITIAL_SNAPSHOT_ID 11 /* ** Functions from file "lsm_ckpt.c". */ | | | 553 554 555 556 557 558 559 560 561 562 563 564 565 566 567 | u32 nWrite; /* Total number of pages written to disk */ }; #define LSM_INITIAL_SNAPSHOT_ID 11 /* ** Functions from file "lsm_ckpt.c". */ int lsmCheckpointWrite(lsm_db *, int, int, u32 *); int lsmCheckpointLevels(lsm_db *, int, void **, int *); int lsmCheckpointLoadLevels(lsm_db *pDb, void *pVal, int nVal); int lsmCheckpointRecover(lsm_db *); int lsmCheckpointDeserialize(lsm_db *, int, u32 *, Snapshot **); int lsmCheckpointLoadWorker(lsm_db *pDb); |
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733 734 735 736 737 738 739 740 741 742 743 744 745 746 | int lsmInfoArrayStructure(lsm_db *pDb, int bBlock, Pgno iFirst, char **pzOut); int lsmInfoArrayPages(lsm_db *pDb, Pgno iFirst, char **pzOut); int lsmConfigMmap(lsm_db *pDb, int *piParam); int lsmEnvOpen(lsm_env *, const char *, int, lsm_file **); int lsmEnvClose(lsm_env *pEnv, lsm_file *pFile); int lsmEnvLock(lsm_env *pEnv, lsm_file *pFile, int iLock, int eLock); int lsmEnvShmMap(lsm_env *, lsm_file *, int, int, void **); void lsmEnvShmBarrier(lsm_env *); void lsmEnvShmUnmap(lsm_env *, lsm_file *, int); void lsmEnvSleep(lsm_env *, int); | > | 734 735 736 737 738 739 740 741 742 743 744 745 746 747 748 | int lsmInfoArrayStructure(lsm_db *pDb, int bBlock, Pgno iFirst, char **pzOut); int lsmInfoArrayPages(lsm_db *pDb, Pgno iFirst, char **pzOut); int lsmConfigMmap(lsm_db *pDb, int *piParam); int lsmEnvOpen(lsm_env *, const char *, int, lsm_file **); int lsmEnvClose(lsm_env *pEnv, lsm_file *pFile); int lsmEnvLock(lsm_env *pEnv, lsm_file *pFile, int iLock, int eLock); int lsmEnvTestLock(lsm_env *pEnv, lsm_file *pFile, int iLock, int nLock, int); int lsmEnvShmMap(lsm_env *, lsm_file *, int, int, void **); void lsmEnvShmBarrier(lsm_env *); void lsmEnvShmUnmap(lsm_env *, lsm_file *, int); void lsmEnvSleep(lsm_env *, int); |
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Changes to src/lsm_ckpt.c.
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918 919 920 921 922 923 924 | ShmHeader *pShm = pDb->pShmhdr; int nInt1; int nInt2; /* Must be holding the WORKER lock to do this. Or DMS2. */ assert( lsmShmAssertLock(pDb, LSM_LOCK_WORKER, LSM_LOCK_EXCL) | | | 918 919 920 921 922 923 924 925 926 927 928 929 930 931 932 | ShmHeader *pShm = pDb->pShmhdr; int nInt1; int nInt2; /* Must be holding the WORKER lock to do this. Or DMS2. */ assert( lsmShmAssertLock(pDb, LSM_LOCK_WORKER, LSM_LOCK_EXCL) || lsmShmAssertLock(pDb, LSM_LOCK_DMS1, LSM_LOCK_EXCL) ); /* Check that the two snapshots match. If not, repair them. */ nInt1 = pShm->aSnap1[CKPT_HDR_NCKPT]; nInt2 = pShm->aSnap2[CKPT_HDR_NCKPT]; if( nInt1!=nInt2 || memcmp(pShm->aSnap1, pShm->aSnap2, nInt2*sizeof(u32)) ){ if( ckptChecksumOk(pShm->aSnap1) ){ |
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Changes to src/lsm_file.c.
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349 350 351 352 353 354 355 356 357 358 359 360 361 362 | return pEnv->xRemap(pFile, szMin, ppMap, pszMap); } int lsmEnvLock(lsm_env *pEnv, lsm_file *pFile, int iLock, int eLock){ if( pFile==0 ) return LSM_OK; return pEnv->xLock(pFile, iLock, eLock); } int lsmEnvShmMap( lsm_env *pEnv, lsm_file *pFile, int iChunk, int sz, void **ppOut | > > > > > > > > > > | 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 | return pEnv->xRemap(pFile, szMin, ppMap, pszMap); } int lsmEnvLock(lsm_env *pEnv, lsm_file *pFile, int iLock, int eLock){ if( pFile==0 ) return LSM_OK; return pEnv->xLock(pFile, iLock, eLock); } int lsmEnvTestLock( lsm_env *pEnv, lsm_file *pFile, int iLock, int nLock, int eLock ){ return pEnv->xTestLock(pFile, iLock, nLock, eLock); } int lsmEnvShmMap( lsm_env *pEnv, lsm_file *pFile, int iChunk, int sz, void **ppOut |
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414 415 416 417 418 419 420 | */ int lsmFsTruncateLog(FileSystem *pFS, i64 nByte){ if( pFS->fdLog==0 ) return LSM_OK; return lsmEnvTruncate(pFS->pEnv, pFS->fdLog, nByte); } /* | | | 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 | */ int lsmFsTruncateLog(FileSystem *pFS, i64 nByte){ if( pFS->fdLog==0 ) return LSM_OK; return lsmEnvTruncate(pFS->pEnv, pFS->fdLog, nByte); } /* ** Truncate the db file to nByte bytes in size. */ int lsmFsTruncateDb(FileSystem *pFS, i64 nByte){ if( pFS->fdDb==0 ) return LSM_OK; return lsmEnvTruncate(pFS->pEnv, pFS->fdDb, nByte); } /* |
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Changes to src/lsm_shared.c.
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208 209 210 211 212 213 214 | ** to as small a size as possible without truncating away any blocks that ** contain data. */ static int dbTruncateFile(lsm_db *pDb){ int rc; assert( pDb->pWorker==0 ); | | | 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 | ** to as small a size as possible without truncating away any blocks that ** contain data. */ static int dbTruncateFile(lsm_db *pDb){ int rc; assert( pDb->pWorker==0 ); assert( lsmShmAssertLock(pDb, LSM_LOCK_DMS1, LSM_LOCK_EXCL) ); rc = lsmCheckpointLoadWorker(pDb); if( rc==LSM_OK ){ DbTruncateCtx ctx; /* Walk the database free-block-list in reverse order. Set ctx.nBlock ** to the block number of the last block in the database that actually |
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238 239 240 241 242 243 244 | pDb->pWorker = 0; return rc; } static void doDbDisconnect(lsm_db *pDb){ int rc; | > > > | | | | | | | | | > > | | | | | | | | > | | | | | > > > > > > > > > > > | | | | | | | | > | < | > > > | | | | | | | | > > | | > | > > > > > < | 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 | pDb->pWorker = 0; return rc; } static void doDbDisconnect(lsm_db *pDb){ int rc; if( pDb->bReadonly ){ lsmShmLock(pDb, LSM_LOCK_DMS3, LSM_LOCK_UNLOCK, 0); }else{ /* Block for an exclusive lock on DMS1. This lock serializes all calls ** to doDbConnect() and doDbDisconnect() across all processes. */ rc = lsmShmLock(pDb, LSM_LOCK_DMS1, LSM_LOCK_EXCL, 1); if( rc==LSM_OK ){ /* Try an exclusive lock on DMS2. If successful, this is the last ** connection to the database. In this case flush the contents of the ** in-memory tree to disk and write a checkpoint. */ rc = lsmShmTestLock(pDb, LSM_LOCK_DMS2, 1, LSM_LOCK_EXCL); if( rc==LSM_OK ){ int bReadonly = 0; /* True if there exist read-only conns. */ /* Flush the in-memory tree, if required. If there is data to flush, ** this will create a new client snapshot in Database.pClient. The ** checkpoint (serialization) of this snapshot may be written to disk ** by the following block. ** ** There is no need to take a WRITER lock here. That there are no ** other locks on DMS2 guarantees that there are no other read-write ** connections at this time (and the lock on DMS1 guarantees that ** no new ones may appear). */ rc = lsmTreeLoadHeader(pDb, 0); if( rc==LSM_OK && (lsmTreeHasOld(pDb) || lsmTreeSize(pDb)>0) ){ rc = lsmFlushTreeToDisk(pDb); } /* Now check if there are any read-only connections. If there are, ** then do not truncate the db file or unlink the shared-memory ** region. */ if( rc==LSM_OK ){ rc = lsmShmTestLock(pDb, LSM_LOCK_DMS3, 1, LSM_LOCK_EXCL); if( rc==LSM_BUSY ){ bReadonly = 1; rc = LSM_OK; } } /* Write a checkpoint to disk. */ if( rc==LSM_OK ){ rc = lsmCheckpointWrite(pDb, (bReadonly==0), 1, 0); } /* If the checkpoint was written successfully, delete the log file ** and, if possible, truncate the database file. */ if( rc==LSM_OK ){ Database *p = pDb->pDatabase; if( bReadonly==0 ){ dbTruncateFile(pDb); if( p->pFile && p->bMultiProc ){ lsmEnvShmUnmap(pDb->pEnv, p->pFile, 1); } } } } } if( pDb->iRwclient>=0 ){ lsmShmLock(pDb, LSM_LOCK_RWCLIENT(pDb->iRwclient), LSM_LOCK_UNLOCK, 0); } lsmShmLock(pDb, LSM_LOCK_DMS2, LSM_LOCK_UNLOCK, 0); lsmShmLock(pDb, LSM_LOCK_DMS1, LSM_LOCK_UNLOCK, 0); } pDb->pShmhdr = 0; } static int doDbConnect(lsm_db *pDb){ const int nUsMax = 100000; /* Max value for nUs */ int nUs = 1000; /* us to wait between DMS1 attempts */ int rc; /* Obtain a pointer to the shared-memory header */ assert( pDb->pShmhdr==0 ); assert( pDb->bReadonly==0 ); rc = lsmShmCacheChunks(pDb, 1); if( rc!=LSM_OK ) return rc; pDb->pShmhdr = (ShmHeader *)pDb->apShm[0]; /* Block for an exclusive lock on DMS1. This lock serializes all calls ** to doDbConnect() and doDbDisconnect() across all processes. */ while( 1 ){ rc = lsmShmLock(pDb, LSM_LOCK_DMS1, LSM_LOCK_EXCL, 1); if( rc!=LSM_BUSY ) break; lsmEnvSleep(pDb->pEnv, nUs); nUs = nUs * 2; if( nUs>nUsMax ) nUs = nUsMax; } if( rc!=LSM_OK ){ pDb->pShmhdr = 0; return rc; } /* Try an exclusive lock on DMS2/DMS3. If successful, this is the first ** and only connection to the database. In this case initialize the ** shared-memory and run log file recovery. */ assert( LSM_LOCK_DMS3==1+LSM_LOCK_DMS2 ); rc = lsmShmTestLock(pDb, LSM_LOCK_DMS2, 2, LSM_LOCK_EXCL); if( rc==LSM_OK ){ memset(pDb->pShmhdr, 0, sizeof(ShmHeader)); rc = lsmCheckpointRecover(pDb); if( rc==LSM_OK ){ rc = lsmLogRecover(pDb); } if( rc==LSM_OK ){ ShmHeader *pShm = pDb->pShmhdr; pShm->aReader[0].iLsmId = lsmCheckpointId(pShm->aSnap1, 0); pShm->aReader[0].iTreeId = pDb->treehdr.iUsedShmid; } }else if( rc==LSM_BUSY ){ rc = LSM_OK; } /* Take a shared lock on DMS2. In multi-process mode this lock "cannot" ** fail, as connections may only hold an exclusive lock on DMS2 if they ** first hold an exclusive lock on DMS1. And this connection is currently ** holding the exclusive lock on DSM1. ** ** However, if some other connection has the database open in single-process ** mode, this operation will fail. In this case, return the error to the ** caller - the attempt to connect to the db has failed. */ if( rc==LSM_OK ){ rc = lsmShmLock(pDb, LSM_LOCK_DMS2, LSM_LOCK_SHARED, 0); } /* If anything went wrong, unlock DMS2. Otherwise, try to take an exclusive ** lock on one of the LSM_LOCK_RWCLIENT() locks. Unlock DMS1 in any case. */ if( rc!=LSM_OK ){ pDb->pShmhdr = 0; }else{ int i; for(i=0; i<LSM_LOCK_NRWCLIENT; i++){ int rc2 = lsmShmLock(pDb, LSM_LOCK_RWCLIENT(i), LSM_LOCK_EXCL, 0); if( rc2==LSM_OK ) pDb->iRwclient = i; if( rc2!=LSM_BUSY ){ |
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840 841 842 843 844 845 846 | ** database itself. ** ** The WORKER lock must not be held when this is called. This is because ** this function may indirectly call fsync(). And the WORKER lock should ** not be held that long (in case it is required by a client flushing an ** in-memory tree to disk). */ | | | 867 868 869 870 871 872 873 874 875 876 877 878 879 880 881 | ** database itself. ** ** The WORKER lock must not be held when this is called. This is because ** this function may indirectly call fsync(). And the WORKER lock should ** not be held that long (in case it is required by a client flushing an ** in-memory tree to disk). */ int lsmCheckpointWrite(lsm_db *pDb, int bTruncate, int bDellog, u32 *pnWrite){ int rc; /* Return Code */ u32 nWrite = 0; assert( pDb->pWorker==0 ); assert( 1 || pDb->pClient==0 ); assert( lsmShmAssertLock(pDb, LSM_LOCK_WORKER, LSM_LOCK_UNLOCK) ); |
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899 900 901 902 903 904 905 906 907 908 909 910 911 912 | ); #endif } if( rc==LSM_OK && bTruncate ){ rc = lsmFsTruncateDb(pDb->pFS, (i64)nBlock*lsmFsBlockSize(pDb->pFS)); } } lsmShmLock(pDb, LSM_LOCK_CHECKPOINTER, LSM_LOCK_UNLOCK, 0); if( pnWrite && rc==LSM_OK ) *pnWrite = nWrite; return rc; } | > > > | 926 927 928 929 930 931 932 933 934 935 936 937 938 939 940 941 942 | ); #endif } if( rc==LSM_OK && bTruncate ){ rc = lsmFsTruncateDb(pDb->pFS, (i64)nBlock*lsmFsBlockSize(pDb->pFS)); } if( rc==LSM_OK && bDellog ){ lsmFsCloseAndDeleteLog(pDb->pFS); } } lsmShmLock(pDb, LSM_LOCK_CHECKPOINTER, LSM_LOCK_UNLOCK, 0); if( pnWrite && rc==LSM_OK ) *pnWrite = nWrite; return rc; } |
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1156 1157 1158 1159 1160 1161 1162 | int lsmBeginRoTrans(lsm_db *db){ int rc = LSM_OK; assert( db->bReadonly && db->pShmhdr==0 ); assert( db->iReader<0 ); if( db->bRoTrans==0 ){ | | > > > > > > > > > > > | | > > > > > > > > | 1186 1187 1188 1189 1190 1191 1192 1193 1194 1195 1196 1197 1198 1199 1200 1201 1202 1203 1204 1205 1206 1207 1208 1209 1210 1211 1212 1213 1214 1215 1216 1217 1218 1219 1220 1221 1222 1223 1224 1225 1226 1227 1228 1229 1230 1231 1232 1233 1234 | int lsmBeginRoTrans(lsm_db *db){ int rc = LSM_OK; assert( db->bReadonly && db->pShmhdr==0 ); assert( db->iReader<0 ); if( db->bRoTrans==0 ){ /* Attempt a shared-lock on DMS1. */ rc = lsmShmLock(db, LSM_LOCK_DMS1, LSM_LOCK_SHARED, 0); if( rc!=LSM_OK ) return rc; rc = lsmShmTestLock( db, LSM_LOCK_RWCLIENT(0), LSM_LOCK_NREADER, LSM_LOCK_SHARED ); if( rc==LSM_OK ){ /* System is not live */ rc = lsmShmLock(db, LSM_LOCK_CHECKPOINTER, LSM_LOCK_SHARED, 0); lsmShmLock(db, LSM_LOCK_DMS1, LSM_LOCK_UNLOCK, 0); if( rc==LSM_OK ){ db->bRoTrans = 1; rc = lsmShmCacheChunks(db, 1); if( rc==LSM_OK ){ db->pShmhdr = (ShmHeader *)db->apShm[0]; memset(db->pShmhdr, 0, sizeof(ShmHeader)); rc = lsmCheckpointRecover(db); if( rc==LSM_OK ){ rc = lsmLogRecover(db); } } } }else if( rc==LSM_BUSY ){ /* System is live! */ rc = lsmShmLock(db, LSM_LOCK_DMS3, LSM_LOCK_SHARED, 0); lsmShmLock(db, LSM_LOCK_DMS1, LSM_LOCK_UNLOCK, 0); if( rc==LSM_OK ){ rc = lsmShmCacheChunks(db, 1); if( rc==LSM_OK ){ db->pShmhdr = (ShmHeader *)db->apShm[0]; } } } if( rc==LSM_OK ){ rc = lsmBeginReadTrans(db); } } |
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1594 1595 1596 1597 1598 1599 1600 1601 1602 1603 1604 1605 1606 1607 | static int lockSharedFile(lsm_env *pEnv, Database *p, int iLock, int eOp){ int rc = LSM_OK; if( p->bMultiProc ){ rc = lsmEnvLock(pEnv, p->pFile, iLock, eOp); } return rc; } /* ** Attempt to obtain the lock identified by the iLock and bExcl parameters. ** If successful, return LSM_OK. If the lock cannot be obtained because ** there exists some other conflicting lock, return LSM_BUSY. If some other ** error occurs, return an LSM error code. ** | > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > | 1643 1644 1645 1646 1647 1648 1649 1650 1651 1652 1653 1654 1655 1656 1657 1658 1659 1660 1661 1662 1663 1664 1665 1666 1667 1668 1669 1670 1671 1672 1673 1674 1675 1676 1677 1678 1679 1680 1681 1682 1683 1684 1685 1686 1687 1688 1689 1690 1691 1692 1693 1694 1695 1696 1697 1698 1699 | static int lockSharedFile(lsm_env *pEnv, Database *p, int iLock, int eOp){ int rc = LSM_OK; if( p->bMultiProc ){ rc = lsmEnvLock(pEnv, p->pFile, iLock, eOp); } return rc; } /* ** Test if it would be possible for connection db to obtain a lock of type ** eType on the nLock locks starting at iLock. If so, return LSM_OK. If it ** would not be possible to obtain the lock due to a lock held by another ** connection, return LSM_BUSY. If an IO or other error occurs (i.e. in the ** lsm_env.xTestLock function), return some other LSM error code. ** ** Note that this function never actually locks the database - it merely ** queries the system to see if there exists a lock that would prevent ** it from doing so. */ int lsmShmTestLock( lsm_db *db, int iLock, int nLock, int eOp ){ int rc = LSM_OK; lsm_db *pIter; Database *p = db->pDatabase; int i; u64 mask = 0; for(i=iLock; i<(iLock+nLock); i++){ mask |= ((u64)1 << (iLock-1)); if( eOp==LSM_LOCK_EXCL ) mask |= ((u64)1 << (iLock+32-1)); } lsmMutexEnter(db->pEnv, p->pClientMutex); for(pIter=p->pConn; pIter; pIter=pIter->pNext){ if( pIter!=db && (pIter->mLock & mask) ) break; } if( pIter ){ rc = LSM_BUSY; }else if( p->bMultiProc ){ rc = lsmEnvTestLock(db->pEnv, p->pFile, iLock, nLock, eOp); } lsmMutexLeave(db->pEnv, p->pClientMutex); return rc; } /* ** Attempt to obtain the lock identified by the iLock and bExcl parameters. ** If successful, return LSM_OK. If the lock cannot be obtained because ** there exists some other conflicting lock, return LSM_BUSY. If some other ** error occurs, return an LSM error code. ** |
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1785 1786 1787 1788 1789 1790 1791 | int lsm_checkpoint(lsm_db *pDb, int *pnKB){ int rc; /* Return code */ u32 nWrite = 0; /* Number of pages checkpointed */ /* Attempt the checkpoint. If successful, nWrite is set to the number of ** pages written between this and the previous checkpoint. */ | | | 1877 1878 1879 1880 1881 1882 1883 1884 1885 1886 1887 1888 1889 1890 1891 | int lsm_checkpoint(lsm_db *pDb, int *pnKB){ int rc; /* Return code */ u32 nWrite = 0; /* Number of pages checkpointed */ /* Attempt the checkpoint. If successful, nWrite is set to the number of ** pages written between this and the previous checkpoint. */ rc = lsmCheckpointWrite(pDb, 0, 0, &nWrite); /* If required, calculate the output variable (KB of data checkpointed). ** Set it to zero if an error occured. */ if( pnKB ){ int nKB = 0; if( rc==LSM_OK && nWrite ){ nKB = (((i64)nWrite * lsmFsPageSize(pDb->pFS)) + 1023) / 1024; |
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Changes to src/lsm_unix.c.
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326 327 328 329 330 331 332 333 334 335 336 337 338 339 | }else{ rc = LSM_IOERR_BKPT; } } return rc; } int lsmPosixOsShmMap(lsm_file *pFile, int iChunk, int sz, void **ppShm){ PosixFile *p = (PosixFile *)pFile; *ppShm = 0; assert( sz==LSM_SHM_CHUNK_SIZE ); if( iChunk>=p->nShm ){ | > > > > > > > > > > > > > > > > > > > > > > > > > > > | 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 | }else{ rc = LSM_IOERR_BKPT; } } return rc; } int lsmPosixOsTestLock(lsm_file *pFile, int iLock, int nLock, int eType){ int rc = LSM_OK; PosixFile *p = (PosixFile *)pFile; static const short aType[3] = { 0, F_RDLCK, F_WRLCK }; struct flock lock; assert( eType==LSM_LOCK_SHARED || eType==LSM_LOCK_EXCL ); assert( aType[LSM_LOCK_SHARED]==F_RDLCK ); assert( aType[LSM_LOCK_EXCL]==F_WRLCK ); assert( eType>=0 && eType<array_size(aType) ); assert( iLock>0 && iLock<=32 ); memset(&lock, 0, sizeof(lock)); lock.l_whence = SEEK_SET; lock.l_len = nLock; lock.l_type = aType[eType]; lock.l_start = (4096-iLock); if( fcntl(p->fd, F_GETLK, &lock) ){ rc = LSM_IOERR_BKPT; }else if( lock.l_type!=F_UNLCK ){ rc = LSM_BUSY; } return rc; } int lsmPosixOsShmMap(lsm_file *pFile, int iChunk, int sz, void **ppShm){ PosixFile *p = (PosixFile *)pFile; *ppShm = 0; assert( sz==LSM_SHM_CHUNK_SIZE ); if( iChunk>=p->nShm ){ |
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678 679 680 681 682 683 684 685 686 687 688 689 690 691 | lsmPosixOsSync, /* xSync */ lsmPosixOsSectorSize, /* xSectorSize */ lsmPosixOsRemap, /* xRemap */ lsmPosixOsFileid, /* xFileid */ lsmPosixOsClose, /* xClose */ lsmPosixOsUnlink, /* xUnlink */ lsmPosixOsLock, /* xLock */ lsmPosixOsShmMap, /* xShmMap */ lsmPosixOsShmBarrier, /* xShmBarrier */ lsmPosixOsShmUnmap, /* xShmUnmap */ /***** memory allocation *********/ 0, /* pMemCtx */ lsmPosixOsMalloc, /* xMalloc */ lsmPosixOsRealloc, /* xRealloc */ | > | 705 706 707 708 709 710 711 712 713 714 715 716 717 718 719 | lsmPosixOsSync, /* xSync */ lsmPosixOsSectorSize, /* xSectorSize */ lsmPosixOsRemap, /* xRemap */ lsmPosixOsFileid, /* xFileid */ lsmPosixOsClose, /* xClose */ lsmPosixOsUnlink, /* xUnlink */ lsmPosixOsLock, /* xLock */ lsmPosixOsTestLock, /* xTestLock */ lsmPosixOsShmMap, /* xShmMap */ lsmPosixOsShmBarrier, /* xShmBarrier */ lsmPosixOsShmUnmap, /* xShmUnmap */ /***** memory allocation *********/ 0, /* pMemCtx */ lsmPosixOsMalloc, /* xMalloc */ lsmPosixOsRealloc, /* xRealloc */ |
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Changes to test/lsm5.test.
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31 32 33 34 35 36 37 38 39 40 41 42 43 44 | forcedelete $file lsm_open db $file db write a alpha db write b bravo db write c charlie db close } #------------------------------------------------------------------------- # When the database system is shut down (i.e. when the last connection # disconnects), an attempt is made to truncate the database file to the # minimum number of blocks required. # # This test case checks that this process does not actually cause the | > > > > > > > > > > > | 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 | forcedelete $file lsm_open db $file db write a alpha db write b bravo db write c charlie db close } proc create_abc_log {file} { forcedelete $file ${file}-2 lsm_open db ${file}-2 db write a alpha db write b bravo db write c charlie file copy ${file}-2 $file file copy ${file}-2-log $file-log db close } #------------------------------------------------------------------------- # When the database system is shut down (i.e. when the last connection # disconnects), an attempt is made to truncate the database file to the # minimum number of blocks required. # # This test case checks that this process does not actually cause the |
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55 56 57 58 59 60 61 | } {} do_test 1.3 { expr [file size test.db] < (64*1024) } 1 #------------------------------------------------------------------------- # Test that if an attempt is made to open a read-write connection to a | | | | < | 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 | } {} do_test 1.3 { expr [file size test.db] < (64*1024) } 1 #------------------------------------------------------------------------- # Test that if an attempt is made to open a read-write connection to a # non-live database that the client does not have permission to write to is # attempted an error is reported. In order to open a read-write connection # to a database, the client requires: # # * read-write access to the db file, # * read-write access to the log file, # * for multi-process mode, read-write access to the shm file. # # In the above, "read-write access" includes the ability to create the db, # log or shm file if it does not exist. # # These tests verify that the lsm_open() command returns LSM_IOERR. At some # point in the future this will be improved. Likely when sqlite4 level tests # for opening read-only databases are added. # foreach {tn filename setup} { 1 test.dir/test.db { # Create a directory "test.dir". forcedelete test.dir file mkdir test.dir |
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105 106 107 108 109 110 111 | create_abc_db test.dir/test.db # Now make test.dir read-only. file attr test.dir -perm r-xr-xr-x } } { | < | | > > > > | > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > | 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 | create_abc_db test.dir/test.db # Now make test.dir read-only. file attr test.dir -perm r-xr-xr-x } } { do_test 2.$tn.1 { eval $setup set rc [catch {lsm_open db $filename} msg] list $rc $msg } {1 {error in lsm_open() - 10}} do_test 2.$tn.2 { eval $setup lsm_open db $filename {readonly 1} set res [list [db_fetch db a] [db_fetch db b] [db_fetch db c]] db close set res } {alpha bravo charlie} } #------------------------------------------------------------------------- # Try having a read-only connection connect to a non-live system where the # log file contains content. In this scenario the read-only client must # read the contents from the log file at the start of each read-transaction. # do_test 3.1 { create_abc_log test.db list [file size test.db] [file size test.db-log] } {0 56} do_test 3.2 { lsm_open db $filename {readonly 1} set res [list [db_fetch db a] [db_fetch db b] [db_fetch db c]] db close set res } {alpha bravo charlie} do_test 3.3 { list [file size test.db] [file size test.db-log] } {0 56} # Now make the same db live and check the read-only connection can still # read it. do_test 3.4 { file exists test.db-shm } 0 do_test 3.5 { lsm_open db_rw test.db file exists test.db-shm } 1 do_test 3.6 { lsm_open db test.db {readonly 1} list [db_fetch db a] [db_fetch db b] [db_fetch db c] } {alpha bravo charlie} # Close the read-write connection. This should cause a checkpoint and delete # the log file, even though the system remains live. do_test 3.7 { db_rw close list [file exists test.db-log] [file exists test.db-shm] } {0 1} # Now close the read-only connection. The system is now non-live, but the # *-shm remains in the file-system (the readonly connection cannot unlink it). do_test 3.8 { db close list [file exists test.db-log] [file exists test.db-shm] } {0 1} finish_test |