From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Date: Thu, 7 Mar 2019 12:46:59 +0300 From: Vladimir Davydov Subject: Re: [tarantool-patches] [PATCH v2 2/3] Put all new rows to the end of journal request Message-ID: <20190307094659.vszahfozunjmvxao@esperanza> References: <2134b8fca0963ebd0a8fb818a66cd05e81ef09a6.1551902962.git.georgy@tarantool.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <2134b8fca0963ebd0a8fb818a66cd05e81ef09a6.1551902962.git.georgy@tarantool.org> To: Georgy Kirichenko Cc: tarantool-patches@freelists.org List-ID: On Wed, Mar 06, 2019 at 11:16:17PM +0300, Georgy Kirichenko wrote: > Form a separate transaction with all local changes in case of replication. > This is important because we should be able to replicate such changes > (e.g. made within an on_replace triggers) back. In the opposite case > local changes will be incorporated into originating transaction and > wold be skipped by originator replica. > > Needed for: #2798 > --- > src/box/txn.c | 36 ++++++++++++++++++++++++++++-------- > src/box/txn.h | 4 ++++ > 2 files changed, 32 insertions(+), 8 deletions(-) > > diff --git a/src/box/txn.c b/src/box/txn.c > index 7900fb3ab..187e1c085 100644 > --- a/src/box/txn.c > +++ b/src/box/txn.c > @@ -141,6 +141,8 @@ txn_begin(bool is_autocommit) > /* Initialize members explicitly to save time on memset() */ > stailq_create(&txn->stmts); > txn->n_rows = 0; > + txn->has_rows_with_lsn = false; > + txn->has_rows_without_lsn = false; > txn->is_autocommit = is_autocommit; > txn->has_triggers = false; > txn->is_aborted = false; > @@ -233,6 +235,8 @@ txn_commit_stmt(struct txn *txn, struct request *request) > if (stmt->space == NULL || !space_is_temporary(stmt->space)) { > if (txn_add_redo(stmt, request) != 0) > goto fail; > + txn->has_rows_with_lsn |= stmt->row->replica_id != 0; > + txn->has_rows_without_lsn |= stmt->row->replica_id == 0; > ++txn->n_rows; > } > /* > @@ -272,13 +276,29 @@ txn_write_to_wal(struct txn *txn) > > struct txn_stmt *stmt; > struct xrow_header **row = req->rows; > - stailq_foreach_entry(stmt, &txn->stmts, next) { > - if (stmt->row == NULL) > - continue; /* A read (e.g. select) request */ > - *row++ = stmt->row; > - req->approx_len += xrow_approx_len(stmt->row); > + if (txn->has_rows_with_lsn) { > + /* Write out rows that already have an assigned lsn. */ > + stailq_foreach_entry(stmt, &txn->stmts, next) { > + if (stmt->row == NULL) > + continue; /* A read (e.g. select) request */ > + if (stmt->row->replica_id == 0) > + continue; /* A row without lsn. */ > + *row++ = stmt->row; > + req->approx_len += xrow_approx_len(stmt->row); > + } > + } > + if (txn->has_rows_without_lsn) { > + /* Write out rows to assign a lsn. */ > + stailq_foreach_entry(stmt, &txn->stmts, next) { > + if (stmt->row == NULL) > + continue; /* A read (e.g. select) request */ > + if (stmt->row->replica_id != 0) > + continue; /* A row with lsn. */ > + *row++ = stmt->row; > + req->approx_len += xrow_approx_len(stmt->row); > + } I liked the previous approach, where you counted remote rows, much more. For one thing, it didn't require two passes over the statement list. I don't understand why you ditched it. > } > - assert(row == req->rows + req->n_rows); > + assert(row == req->rows + txn->n_rows); > > ev_tstamp start = ev_monotonic_now(loop()); > int64_t res = journal_write(req); > @@ -399,8 +419,6 @@ txn_rollback() > txn_stmt_unref_tuples(stmt); > > TRASH(txn); > - /** Free volatile txn memory. */ > - fiber_gc(); > fiber_set_txn(fiber(), NULL); > } > > @@ -480,6 +498,8 @@ box_txn_rollback() > return -1; > } > txn_rollback(); /* doesn't throw */ > + /** Free volatile txn memory. */ > + fiber_gc(); > return 0; > } As I told you during the previous review session, moving fiber_gc from txn_rollback to box_txn_rollback is a separate change. In fact, it's a follow-up for 77fa1736dbb9 ("box: factor fiber_gc out of txn_commit"). Please submit it in a separate patch with a proper commentary.