From: jiangwen jiang Date: October 28 2011 7:38am Subject: how to understand seconds_behind_master List-Archive: http://lists.mysql.com/mysql/226193 Message-Id: MIME-Version: 1.0 Content-Type: multipart/alternative; boundary=000e0cd2e56ce0a9d004b056f9d7 --000e0cd2e56ce0a9d004b056f9d7 Content-Type: text/plain; charset=ISO-8859-1 Hi, all: I am confusing with seconds_behind_master, in mysql manual, it says: In essence, this field measures the time difference in seconds between the slave SQL thread and the slave I/O thread. how to understand this description: 1. seconds_behinds_master = ts in SQL thread - ts in I/O thread, or seconds_behinds_mater = ts in I/O thread - ts in SQL thead 2. how to get the timestamp in SQL and I/O thread, when this time will update? Thanks W.J --000e0cd2e56ce0a9d004b056f9d7--