From: jiangwen jiang Date: October 28 2011 8:53am Subject: Re: how to understand seconds_behind_master List-Archive: http://lists.mysql.com/mysql/226196 Message-Id: MIME-Version: 1.0 Content-Type: multipart/alternative; boundary=000e0cd2e56c041aa204b05806b5 --000e0cd2e56c041aa204b05806b5 Content-Type: text/plain; charset=ISO-8859-1 someone say: seconds_behinds_master = time in I/O thread - time in SQL thread time in I/O thread is current timestamp, time in SQL thread is the timestamp record in binlog, this binlog is originates from master, so it is the timestamp when binlog is generated in master. Is this correct? 2011/10/28 jiangwen jiang > 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 > > > --000e0cd2e56c041aa204b05806b5--