From aabcc4fb12868516f1c5e04507c551529c18b14f Mon Sep 17 00:00:00 2001 From: Markus Makela Date: Fri, 15 Apr 2016 10:18:50 +0300 Subject: [PATCH] Added clarifying comments to event distribution code When a slave transitions from catchup mode to up-to-date mode, it is possible that events are being distributed and the slave appears to be lagging behind. The added comment explain why it happens and how it is handled to make the code clearer. --- server/modules/routing/binlog/blr_master.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/server/modules/routing/binlog/blr_master.c b/server/modules/routing/binlog/blr_master.c index 32fdf61d7..bfcddee76 100644 --- a/server/modules/routing/binlog/blr_master.c +++ b/server/modules/routing/binlog/blr_master.c @@ -1927,6 +1927,10 @@ blr_distribute_binlog_record(ROUTER_INSTANCE *router, REP_HEADER *hdr, uint8_t * slave->binlogfile, slave->binlog_pos, hdr->next_pos - hdr->event_size); } + /* If none of the above conditions were met, a slave in catchup + * mode transitioned into up-to-date mode while we were + * distributing events. The slave needs to be forced into + * catchup mode since it isn't up to date anymore. */ } else if (rotate) {