Tagged with "binlog"
Fun MySQL fact of the day: absolute delay
Yesterday, we established an understanding ofSeconds_Behind_Master
and identified some of its shortcomings. While it's not a completely useless metric, it's also not a very helpful one. What we probably really want is an absolute measure of replication latency, and we'll look at one way of accomplishing that today. ... read more
Fun MySQL fact of the day: seconds behind master
Yesterday, we started considering some causes of replication delay. Given L. Peter Deutsch's assertions about the fallacies of distributed computing, I think we can safely agree that replication delay is going to happen. And, not only will it happen, it will happen frequently and unpredictably. So while we ... read moreFun MySQL fact of the day: replication delay
Now that we have a basic understanding of how MySQL's replication mechanism works, let's poke it with a stick and see what happens. That is, of course, fun. ... read moreFun MySQL fact of the day: the SQL thread
Yesterday, we looked at how a MySQL replica's IO thread downloads a master's binary logs and stores them as its own "relay logs". We also said this happens until the IO thread is stopped or the replica database runs out of disk space, and while that's true, there's another ... read moreFun MySQL fact of the day: the IO thread
On Friday, we looked at a pretty fun and very handy use of the MySQL binary log to perform point-in-time recovery during a make-believe disaster. We're going to circle back to point-in-time recovery a bit later this week, but I want to first start looking at MySQL's replication implementation. ... read more
Fun MySQL fact of the day: mysqlbinlog
It's 3:37 A.M. when your phone blares out. Your hands are numbed from the early on-set of carpel tunnel and you can't hush the wailing siren that has become of your phone. With adrenaline coursing through your body, you shove your phone under your pillow mashing around in the dark ... read more
Fun MySQL fact of the day: the binary log is binary
Yesterday, we started to form a (somewhat broken) mental model of MySQL's binary log. Today, we'll start taking a look at the on-disk representation before diving right in and using some of MySQL's tools to do fun (and useful!) things. ... read moreFun MySQL fact of the day: the binary log
The very first Fun MySQL fact of the day discussed a MySQL flag,sync_binlog
, which is, indeed, a counter, and while we discussed that it can be used to tune a MySQL database's durability, we didn't really dig much deeper. Over the next little while, we'll do just that ... read more
Fun MySQL fact of the day: sync_binlog
is a counter
The D
in ACID stands for Durability, which is the property that guarantees a committed transaction will be permanently recorded. Perfect durability is impossible, but MySQL allows us to improve our ability to offer this guarantee this through the sync_binlog
flag. ... read more