예제 #1
0
파일: txn_log.c 프로젝트: DINKIN/mongo
/*
 * __wt_txn_checkpoint_log --
 *	Write a log record for a checkpoint operation.
 */
int
__wt_txn_checkpoint_log(
    WT_SESSION_IMPL *session, bool full, uint32_t flags, WT_LSN *lsnp)
{
	WT_CONNECTION_IMPL *conn;
	WT_DECL_ITEM(logrec);
	WT_DECL_RET;
	WT_ITEM *ckpt_snapshot, empty;
	WT_LSN *ckpt_lsn;
	WT_TXN *txn;
	WT_TXN_GLOBAL *txn_global;
	uint8_t *end, *p;
	size_t recsize;
	uint32_t i, rectype;
	const char *fmt;

	conn = S2C(session);
	txn_global = &conn->txn_global;
	txn = &session->txn;
	ckpt_lsn = &txn->ckpt_lsn;

	/*
	 * If this is a file sync, log it unless there is a full checkpoint in
	 * progress.
	 */
	if (!full) {
		if (txn->full_ckpt) {
			if (lsnp != NULL)
				*lsnp = *ckpt_lsn;
			return (0);
		}
		return (__txn_log_file_sync(session, flags, lsnp));
	}

	switch (flags) {
	case WT_TXN_LOG_CKPT_PREPARE:
		txn->full_ckpt = true;

		if (conn->compat_major >= WT_LOG_V2) {
			/*
			 * Write the system log record containing a checkpoint
			 * start operation.
			 */
			rectype = WT_LOGREC_SYSTEM;
			fmt = WT_UNCHECKED_STRING(I);
			WT_ERR(__wt_struct_size(
			    session, &recsize, fmt, rectype));
			WT_ERR(__wt_logrec_alloc(session, recsize, &logrec));

			WT_ERR(__wt_struct_pack(session,
			    (uint8_t *)logrec->data + logrec->size, recsize,
			    fmt, rectype));
			logrec->size += (uint32_t)recsize;
			WT_ERR(__wt_logop_checkpoint_start_pack(
			    session, logrec));
			WT_ERR(__wt_log_write(session, logrec, ckpt_lsn, 0));
		} else {
			WT_ERR(__wt_log_printf(session,
			    "CHECKPOINT: Starting record"));
			WT_ERR(__wt_log_flush_lsn(session, ckpt_lsn, true));
		}

		/*
		 * We take and immediately release the visibility lock.
		 * Acquiring the write lock guarantees that any transaction
		 * that has written to the log has also made its transaction
		 * visible at this time.
		 */
		__wt_writelock(session, &txn_global->visibility_rwlock);
		__wt_writeunlock(session, &txn_global->visibility_rwlock);

		/*
		 * We need to make sure that the log records in the checkpoint
		 * LSN are on disk.  In particular to make sure that the
		 * current log file exists.
		 */
		WT_ERR(__wt_log_force_sync(session, ckpt_lsn));
		break;
	case WT_TXN_LOG_CKPT_START:
		/* Take a copy of the transaction snapshot. */
		txn->ckpt_nsnapshot = txn->snapshot_count;
		recsize = (size_t)txn->ckpt_nsnapshot * WT_INTPACK64_MAXSIZE;
		WT_ERR(__wt_scr_alloc(session, recsize, &txn->ckpt_snapshot));
		p = txn->ckpt_snapshot->mem;
		end = p + recsize;
		for (i = 0; i < txn->snapshot_count; i++)
			WT_ERR(__wt_vpack_uint(
			    &p, WT_PTRDIFF(end, p), txn->snapshot[i]));
		break;
	case WT_TXN_LOG_CKPT_STOP:
		/*
		 * During a clean connection close, we get here without the
		 * prepare or start steps.  In that case, log the current LSN
		 * as the checkpoint LSN.
		 */
		if (!txn->full_ckpt) {
			txn->ckpt_nsnapshot = 0;
			WT_CLEAR(empty);
			ckpt_snapshot = &empty;
			WT_ERR(__wt_log_flush_lsn(session, ckpt_lsn, true));
		} else
			ckpt_snapshot = txn->ckpt_snapshot;

		/* Write the checkpoint log record. */
		rectype = WT_LOGREC_CHECKPOINT;
		fmt = WT_UNCHECKED_STRING(IIIIu);
		WT_ERR(__wt_struct_size(session, &recsize,
		    fmt, rectype, ckpt_lsn->l.file, ckpt_lsn->l.offset,
		    txn->ckpt_nsnapshot, ckpt_snapshot));
		WT_ERR(__wt_logrec_alloc(session, recsize, &logrec));

		WT_ERR(__wt_struct_pack(session,
		    (uint8_t *)logrec->data + logrec->size, recsize,
		    fmt, rectype, ckpt_lsn->l.file, ckpt_lsn->l.offset,
		    txn->ckpt_nsnapshot, ckpt_snapshot));
		logrec->size += (uint32_t)recsize;
		WT_ERR(__wt_log_write(session, logrec, lsnp,
		    F_ISSET(conn, WT_CONN_CKPT_SYNC) ?
		    WT_LOG_FSYNC : 0));

		/*
		 * If this full checkpoint completed successfully and there is
		 * no hot backup in progress and this is not an unclean
		 * recovery, tell the logging subsystem the checkpoint LSN so
		 * that it can archive.  Do not update the logging checkpoint
		 * LSN if this is during a clean connection close, only during
		 * a full checkpoint.  A clean close may not update any
		 * metadata LSN and we do not want to archive in that case.
		 */
		if (!conn->hot_backup &&
		    (!FLD_ISSET(conn->log_flags, WT_CONN_LOG_RECOVER_DIRTY) ||
		    FLD_ISSET(conn->log_flags, WT_CONN_LOG_FORCE_DOWNGRADE)) &&
		    txn->full_ckpt)
			__wt_log_ckpt(session, ckpt_lsn);

		/* FALLTHROUGH */
	case WT_TXN_LOG_CKPT_CLEANUP:
		/* Cleanup any allocated resources */
		WT_INIT_LSN(ckpt_lsn);
		txn->ckpt_nsnapshot = 0;
		__wt_scr_free(session, &txn->ckpt_snapshot);
		txn->full_ckpt = false;
		break;
	WT_ILLEGAL_VALUE_ERR(session);
	}

err:	__wt_logrec_free(session, &logrec);
	return (ret);
}
예제 #2
0
파일: txn_log.c 프로젝트: sylvanchil/mongo
/*
 * __wt_txn_checkpoint_log --
 *	Write a log record for a checkpoint operation.
 */
int
__wt_txn_checkpoint_log(
    WT_SESSION_IMPL *session, bool full, uint32_t flags, WT_LSN *lsnp)
{
	WT_DECL_ITEM(logrec);
	WT_DECL_RET;
	WT_ITEM *ckpt_snapshot, empty;
	WT_LSN *ckpt_lsn;
	WT_TXN *txn;
	uint8_t *end, *p;
	size_t recsize;
	uint32_t i, rectype = WT_LOGREC_CHECKPOINT;
	const char *fmt = WT_UNCHECKED_STRING(IIQIU);

	txn = &session->txn;
	ckpt_lsn = &txn->ckpt_lsn;

	/*
	 * If this is a file sync, log it unless there is a full checkpoint in
	 * progress.
	 */
	if (!full) {
		if (txn->full_ckpt) {
			if (lsnp != NULL)
				*lsnp = *ckpt_lsn;
			return (0);
		}
		return (__txn_log_file_sync(session, flags, lsnp));
	}

	switch (flags) {
	case WT_TXN_LOG_CKPT_PREPARE:
		txn->full_ckpt = true;
		WT_ERR(__wt_log_flush_lsn(session, ckpt_lsn, true));
		/*
		 * We need to make sure that the log records in the checkpoint
		 * LSN are on disk.  In particular to make sure that the
		 * current log file exists.
		 */
		WT_ERR(__wt_log_force_sync(session, ckpt_lsn));
		break;
	case WT_TXN_LOG_CKPT_START:
		/* Take a copy of the transaction snapshot. */
		txn->ckpt_nsnapshot = txn->snapshot_count;
		recsize = txn->ckpt_nsnapshot * WT_INTPACK64_MAXSIZE;
		WT_ERR(__wt_scr_alloc(session, recsize, &txn->ckpt_snapshot));
		p = txn->ckpt_snapshot->mem;
		end = p + recsize;
		for (i = 0; i < txn->snapshot_count; i++)
			WT_ERR(__wt_vpack_uint(
			    &p, WT_PTRDIFF(end, p), txn->snapshot[i]));
		break;
	case WT_TXN_LOG_CKPT_STOP:
		/*
		 * During a clean connection close, we get here without the
		 * prepare or start steps.  In that case, log the current LSN
		 * as the checkpoint LSN.
		 */
		if (!txn->full_ckpt) {
			txn->ckpt_nsnapshot = 0;
			WT_CLEAR(empty);
			ckpt_snapshot = &empty;
			WT_ERR(__wt_log_flush_lsn(session, ckpt_lsn, true));
		} else
			ckpt_snapshot = txn->ckpt_snapshot;

		/* Write the checkpoint log record. */
		WT_ERR(__wt_struct_size(session, &recsize, fmt,
		    rectype, ckpt_lsn->file, ckpt_lsn->offset,
		    txn->ckpt_nsnapshot, ckpt_snapshot));
		WT_ERR(__wt_logrec_alloc(session, recsize, &logrec));

		WT_ERR(__wt_struct_pack(session,
		    (uint8_t *)logrec->data + logrec->size, recsize, fmt,
		    rectype, ckpt_lsn->file, ckpt_lsn->offset,
		    txn->ckpt_nsnapshot, ckpt_snapshot));
		logrec->size += (uint32_t)recsize;
		WT_ERR(__wt_log_write(session, logrec, lsnp,
		    F_ISSET(S2C(session), WT_CONN_CKPT_SYNC) ?
		    WT_LOG_FSYNC : 0));

		/*
		 * If this full checkpoint completed successfully and there is
		 * no hot backup in progress, tell the logging subsystem the
		 * checkpoint LSN so that it can archive.  Do not update the
		 * logging checkpoint LSN if this is during a clean connection
		 * close, only during a full checkpoint.  A clean close may not
		 * update any metadata LSN and we do not want to archive in
		 * that case.
		 */
		if (!S2C(session)->hot_backup && txn->full_ckpt)
			WT_ERR(__wt_log_ckpt(session, ckpt_lsn));

		/* FALLTHROUGH */
	case WT_TXN_LOG_CKPT_CLEANUP:
		/* Cleanup any allocated resources */
		WT_INIT_LSN(ckpt_lsn);
		txn->ckpt_nsnapshot = 0;
		__wt_scr_free(session, &txn->ckpt_snapshot);
		txn->full_ckpt = false;
		break;
	WT_ILLEGAL_VALUE_ERR(session);
	}

err:	__wt_logrec_free(session, &logrec);
	return (ret);
}