Ejemplo n.º 1
0
/*
 * __txn_logrec_init --
 *	Allocate and initialize a buffer for a transaction's log records.
 */
static int
__txn_logrec_init(WT_SESSION_IMPL *session)
{
	WT_DECL_ITEM(logrec);
	WT_DECL_RET;
	WT_TXN *txn;
	const char *fmt = WT_UNCHECKED_STRING(Iq);
	uint32_t rectype = WT_LOGREC_COMMIT;
	size_t header_size;

	txn = &session->txn;
	if (txn->logrec != NULL)
		return (0);

	WT_ASSERT(session, txn->id != WT_TXN_NONE);
	WT_RET(__wt_struct_size(session, &header_size, fmt, rectype, txn->id));
	WT_RET(__wt_logrec_alloc(session, header_size, &logrec));

	WT_ERR(__wt_struct_pack(session,
	    (uint8_t *)logrec->data + logrec->size, header_size,
	    fmt, rectype, txn->id));
	logrec->size += (uint32_t)header_size;
	txn->logrec = logrec;

	if (0) {
err:		__wt_logrec_free(session, &logrec);
	}
	return (ret);
}
Ejemplo n.º 2
0
/*
 * __txn_log_file_sync --
 *	Write a log record for a file sync.
 */
static int
__txn_log_file_sync(WT_SESSION_IMPL *session, uint32_t flags, WT_LSN *lsnp)
{
	WT_BTREE *btree;
	WT_DECL_RET;
	WT_DECL_ITEM(logrec);
	const char *fmt = WT_UNCHECKED_STRING(III);
	size_t header_size;
	uint32_t rectype = WT_LOGREC_FILE_SYNC;
	int start;

	btree = S2BT(session);
	start = LF_ISSET(WT_TXN_LOG_CKPT_START);

	WT_RET(__wt_struct_size(
	    session, &header_size, fmt, rectype, btree->id, start));
	WT_RET(__wt_logrec_alloc(session, header_size, &logrec));

	WT_ERR(__wt_struct_pack(session,
	    (uint8_t *)logrec->data + logrec->size, header_size,
	    fmt, rectype, btree->id, start));
	logrec->size += (uint32_t)header_size;

	WT_ERR(__wt_log_write(session, logrec, lsnp, 0));
err:	__wt_logrec_free(session, &logrec);
	return (ret);
}
Ejemplo n.º 3
0
/*
 * __wt_txn_release --
 *	Release the resources associated with the current transaction.
 */
void
__wt_txn_release(WT_SESSION_IMPL *session)
{
	WT_TXN *txn;
	WT_TXN_GLOBAL *txn_global;
	WT_TXN_STATE *txn_state;

	txn = &session->txn;
	txn_global = &S2C(session)->txn_global;
	txn_state = WT_SESSION_TXN_STATE(session);

	WT_ASSERT(session, txn->mod_count == 0);
	txn->notify = NULL;

	/* Clear the transaction's ID from the global table. */
	if (WT_SESSION_IS_CHECKPOINT(session)) {
		WT_ASSERT(session, txn_state->id == WT_TXN_NONE);
		txn->id = txn_global->checkpoint_state.id =
		    txn_global->checkpoint_state.pinned_id = WT_TXN_NONE;

		/*
		 * Be extra careful to cleanup everything for checkpoints: once
		 * the global checkpoint ID is cleared, we can no longer tell
		 * if this session is doing a checkpoint.
		 */
		txn_global->checkpoint_id = 0;
	} else if (F_ISSET(txn, WT_TXN_HAS_ID)) {
		WT_ASSERT(session,
		    !WT_TXNID_LT(txn->id, txn_global->last_running));

		WT_ASSERT(session, txn_state->id != WT_TXN_NONE &&
		    txn->id != WT_TXN_NONE);
		WT_PUBLISH(txn_state->id, WT_TXN_NONE);

		txn->id = WT_TXN_NONE;
	}

	__wt_txn_clear_commit_timestamp(session);
	__wt_txn_clear_read_timestamp(session);

	/* Free the scratch buffer allocated for logging. */
	__wt_logrec_free(session, &txn->logrec);

	/* Discard any memory from the session's stash that we can. */
	WT_ASSERT(session, __wt_session_gen(session, WT_GEN_SPLIT) == 0);
	__wt_stash_discard(session);

	/*
	 * Reset the transaction state to not running and release the snapshot.
	 */
	__wt_txn_release_snapshot(session);
	txn->isolation = session->isolation;

	/* Ensure the transaction flags are cleared on exit */
	txn->flags = 0;
}
Ejemplo n.º 4
0
/*
 * __wt_log_system_record --
 *	Write a system log record for the previous LSN.
 */
int
__wt_log_system_record(
    WT_SESSION_IMPL *session, WT_FH *log_fh, WT_LSN *lsn)
{
	WT_DECL_ITEM(logrec_buf);
	WT_DECL_RET;
	WT_LOG *log;
	WT_LOG_RECORD *logrec;
	WT_LOGSLOT tmp;
	WT_MYSLOT myslot;
	const char *fmt = WT_UNCHECKED_STRING(I);
	uint32_t rectype = WT_LOGREC_SYSTEM;
	size_t recsize;

	log = S2C(session)->log;
	WT_RET(__wt_logrec_alloc(session, log->allocsize, &logrec_buf));
	memset((uint8_t *)logrec_buf->mem, 0, log->allocsize);

	WT_ERR(__wt_struct_size(session, &recsize, fmt, rectype));
	WT_ERR(__wt_struct_pack(session,
	    (uint8_t *)logrec_buf->data + logrec_buf->size, recsize, fmt,
	    rectype));
	logrec_buf->size += recsize;
	WT_ERR(__wt_logop_prev_lsn_pack(session, logrec_buf, lsn));
	WT_ASSERT(session, logrec_buf->size <= log->allocsize);

	logrec = (WT_LOG_RECORD *)logrec_buf->mem;

	/*
	 * We know system records are this size.  And we have to adjust
	 * the size now because we're not going through the normal log
	 * write path and the packing functions needed the correct offset
	 * earlier.
	 */
	logrec_buf->size = logrec->len = log->allocsize;

	/* We do not compress nor encrypt this record. */
	logrec->checksum = 0;
	logrec->flags = 0;
	__wt_log_record_byteswap(logrec);
	logrec->checksum = __wt_checksum(logrec, log->allocsize);
#ifdef WORDS_BIGENDIAN
	logrec->checksum = __wt_bswap32(logrec->checksum);
#endif
	WT_CLEAR(tmp);
	memset(&myslot, 0, sizeof(myslot));
	myslot.slot = &tmp;
	__wt_log_slot_activate(session, &tmp);
	/*
	 * Override the file handle to the one we're using.
	 */
	tmp.slot_fh = log_fh;
	WT_ERR(__wt_log_fill(session, &myslot, true, logrec_buf, NULL));
err:	__wt_logrec_free(session, &logrec_buf);
	return (ret);
}
Ejemplo n.º 5
0
/*
 * __wt_txn_log_commit --
 *	Write the operations of a transaction to the log at commit time.
 */
int
__wt_txn_log_commit(WT_SESSION_IMPL *session, const char *cfg[])
{
	WT_DECL_RET;
	WT_DECL_ITEM(logrec);
	WT_TXN *txn;
	WT_TXN_OP *op;
	const char *fmt = WT_UNCHECKED_STRING(Iq);
	size_t header_size;
	uint32_t rectype = WT_LOGREC_COMMIT;
	u_int i;

	WT_UNUSED(cfg);
	txn = &session->txn;

	WT_RET(__wt_struct_size(session, &header_size, fmt, rectype, txn->id));
	WT_RET(__wt_logrec_alloc(session, header_size, &logrec));

	WT_ERR(__wt_struct_pack(session,
	    (uint8_t *)logrec->data + logrec->size, header_size,
	    fmt, rectype, txn->id));
	logrec->size += (uint32_t)header_size;

	/* Write updates to the log. */
	for (i = 0, op = txn->mod; i < txn->mod_count; i++, op++)
		switch (op->type) {
		case TXN_OP_BASIC:
			WT_ERR(__txn_op_log(session, logrec, op));
			break;
		case TXN_OP_INMEM:
		case TXN_OP_REF:
			/* Nothing to log, we're done. */
			break;
		case TXN_OP_TRUNCATE_COL:
			WT_ERR(__wt_logop_col_truncate_pack(session, logrec,
			    op->fileid,
			    op->u.truncate_col.start, op->u.truncate_col.stop));
			break;
		case TXN_OP_TRUNCATE_ROW:
			WT_ERR(__wt_logop_row_truncate_pack(session, logrec,
			    op->fileid,
			    &op->u.truncate_row.start, &op->u.truncate_row.stop,
			    (uint32_t)op->u.truncate_row.mode));
			break;
		}

	WT_ERR(__wt_log_write(session,
	    logrec, NULL, S2C(session)->txn_logsync));

err:	__wt_logrec_free(session, &logrec);
	return (ret);
}
Ejemplo n.º 6
0
/*
 * __wt_txn_release --
 *	Release the resources associated with the current transaction.
 */
void
__wt_txn_release(WT_SESSION_IMPL *session)
{
	WT_TXN *txn;
	WT_TXN_GLOBAL *txn_global;
	WT_TXN_STATE *txn_state;

	txn = &session->txn;
	WT_ASSERT(session, txn->mod_count == 0);
	txn->notify = NULL;

	txn_global = &S2C(session)->txn_global;
	txn_state = WT_SESSION_TXN_STATE(session);

	/* Clear the transaction's ID from the global table. */
	if (WT_SESSION_IS_CHECKPOINT(session)) {
		WT_ASSERT(session, txn_state->id == WT_TXN_NONE);
		txn->id = WT_TXN_NONE;

		/* Clear the global checkpoint transaction IDs. */
		txn_global->checkpoint_id = 0;
		txn_global->checkpoint_pinned = WT_TXN_NONE;
	} else if (F_ISSET(txn, WT_TXN_HAS_ID)) {
		WT_ASSERT(session,
		    !WT_TXNID_LT(txn->id, txn_global->last_running));

		WT_ASSERT(session, txn_state->id != WT_TXN_NONE &&
		    txn->id != WT_TXN_NONE);
		WT_PUBLISH(txn_state->id, WT_TXN_NONE);
		txn->id = WT_TXN_NONE;
	}

	/* Free the scratch buffer allocated for logging. */
	__wt_logrec_free(session, &txn->logrec);

	/* Discard any memory from the session's split stash that we can. */
	WT_ASSERT(session, session->split_gen == 0);
	if (session->split_stash_cnt > 0)
		__wt_split_stash_discard(session);

	/*
	 * Reset the transaction state to not running and release the snapshot.
	 */
	__wt_txn_release_snapshot(session);
	txn->isolation = session->isolation;
	/* Ensure the transaction flags are cleared on exit */
	txn->flags = 0;
}
Ejemplo n.º 7
0
Archivo: txn.c Proyecto: To4e/mongo
/*
 * __wt_txn_release --
 *	Release the resources associated with the current transaction.
 */
void
__wt_txn_release(WT_SESSION_IMPL *session)
{
	WT_TXN *txn;
	WT_TXN_GLOBAL *txn_global;
	WT_TXN_STATE *txn_state;
	int was_oldest;

	txn = &session->txn;
	WT_ASSERT(session, txn->mod_count == 0);
	txn->notify = NULL;

	txn_global = &S2C(session)->txn_global;
	txn_state = WT_SESSION_TXN_STATE(session);
	was_oldest = 0;

	/* Clear the transaction's ID from the global table. */
	if (WT_SESSION_IS_CHECKPOINT(session)) {
		WT_ASSERT(session, txn_state->id == WT_TXN_NONE);
		txn->id = WT_TXN_NONE;

		/* Clear the global checkpoint transaction IDs. */
		txn_global->checkpoint_id = 0;
		txn_global->checkpoint_pinned = WT_TXN_NONE;
	} else if (F_ISSET(txn, WT_TXN_HAS_ID)) {
		WT_ASSERT(session,
		    !WT_TXNID_LT(txn->id, txn_global->last_running));

		WT_ASSERT(session, txn_state->id != WT_TXN_NONE &&
		    txn->id != WT_TXN_NONE);
		WT_PUBLISH(txn_state->id, WT_TXN_NONE);

		/* Quick check for the oldest transaction. */
		was_oldest = (txn->id == txn_global->last_running);
		txn->id = WT_TXN_NONE;
	}

	/* Free the scratch buffer allocated for logging. */
	__wt_logrec_free(session, &txn->logrec);

	/* Discard any memory from the session's split stash that we can. */
	WT_ASSERT(session, session->split_gen == 0);
	if (session->split_stash_cnt > 0)
		__wt_split_stash_discard(session);

	/*
	 * Reset the transaction state to not running and release the snapshot.
	 */
	__wt_txn_release_snapshot(session);
	txn->isolation = session->isolation;
	/* Ensure the transaction flags are cleared on exit */
	txn->flags = 0;

	/*
	 * When the oldest transaction in the system completes, bump the oldest
	 * ID.  This is racy and so not guaranteed, but in practice it keeps
	 * the oldest ID from falling too far behind.
	 */
	if (was_oldest)
		__wt_txn_update_oldest(session, 1);
}
Ejemplo n.º 8
0
/*
 * __wt_txn_checkpoint_log --
 *	Write a log record for a checkpoint operation.
 */
int
__wt_txn_checkpoint_log(
    WT_SESSION_IMPL *session, int full, uint32_t flags, WT_LSN *lsnp)
{
	WT_DECL_RET;
	WT_DECL_ITEM(logrec);
	WT_LSN *ckpt_lsn;
	WT_TXN *txn;
	const char *fmt = WT_UNCHECKED_STRING(IIQIU);
	uint8_t *end, *p;
	size_t recsize;
	uint32_t i, rectype = WT_LOGREC_CHECKPOINT;

	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);
		} else
			return (__txn_log_file_sync(session, flags, lsnp));
	}

	switch (flags) {
	case WT_TXN_LOG_CKPT_PREPARE:
		txn->full_ckpt = 1;
		*ckpt_lsn = S2C(session)->log->alloc_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;
			*ckpt_lsn = S2C(session)->log->alloc_lsn;
		}

		/* Write the checkpoint log record. */
		WT_ERR(__wt_struct_size(session, &recsize, fmt,
		    rectype, ckpt_lsn->file, ckpt_lsn->offset,
		    txn->ckpt_nsnapshot, &txn->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, &txn->ckpt_snapshot));
		logrec->size += (uint32_t)recsize;
		WT_ERR(__wt_log_write(session, logrec, lsnp, 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.
		 */
		if (!S2C(session)->hot_backup)
			WT_ERR(__wt_log_ckpt(session, ckpt_lsn));

		/* FALLTHROUGH */
	case WT_TXN_LOG_CKPT_FAIL:
		/* Cleanup any allocated resources */
		INIT_LSN(ckpt_lsn);
		txn->ckpt_nsnapshot = 0;
		__wt_scr_free(&txn->ckpt_snapshot);
		txn->full_ckpt = 0;
		break;
	}

err:	__wt_logrec_free(session, &logrec);
	return (ret);
}
Ejemplo n.º 9
0
/*
 * __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);
}
Ejemplo n.º 10
0
/*
 * __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);
}