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Displaying posts with tag: commit (reset)
When COMMIT Is the Slowest Query

When COMMIT is the slowest query, it means your storage is slow. Let’s look at an example.

When COMMIT Is the Slowest Query

When COMMIT is the slowest query, it means your storage is slow. Let’s look at an example.

Associating git hooks with js syntax check

This is a followup article from my previous post.


Here we will be using git pre-commit to check for syntax error while committing in JavaScript files.

We will need nodejs in our system. Please check https://nodejs.org/en/ for downloading and install steps.

Note: I am using ubuntu 14.04 for this setup.

Steps to add pre-commit JavaScript syntax check with git:

1. Use npm to install jslint package globally in your system.

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Associating git hooks with php syntax check

Many a times we have faced this problem that when we commit something and it breaks something on the server due to some syntax error.
I know that these can be caught by IDEs and good editors, but sometimes there might be an syntax error introduced after a code merge conflict resolution and commit.
To address this, we can use git pre-commit hooks to check for any syntax errors in the to be committed files.

There is a good script I found which does this at https://github.com/ReekenX/phpcheck-git

Steps to add pre-commit php syntax check with git:

(Issue …

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The strange commit behavior and the invisible Xid_log_event

Did you see this when you are migrating from your lovely MySQL 5.1 to MySQL 5.5?
Oh, sorry, you remain attached to your pretty 4.1. Yes, I know, MyISAM has become so important in your life…

Ok, seriously, I would like to share this little observation I made recently when switching to MySQL 5.5 on one slave.
You can see below two graphs for the transactional activity, there is exactly the same volume of update, delete and insert queries :

MySQL 5.1

MySQL 5.5

But the gray area represents the number of commit per second.
I find that I have much more commit with MySQL 5.5, why? …

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MySQL 5.6 Replication – New Early Access Features

At OSCON 2011 last week, Oracle delivered more early access (labs) features for MySQL 5.6 replication. These features are focused on better integration, performance and data integrity:

- The Binlog API: empowering the community to seamlessly integrate MySQL with other applications and data stores;

- Binlog Group Commit and Enhanced Multi-Threaded Slaves: continuing to deliver major improvements to replication performance;

- Durable Slave Reads: further enhancing data integrity.

These new features build on the significant replication enhancements announced as part of the MySQL 5.6.2 Development Milestone Release back in April.

We are always listening to our customers and community. And, based on their needs and input, the MySQL engineering team continues to take …

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A rollback query on innodb does not reset the auto_increment counter?!?!?

So, this is a small blog that I felt necessity to do cause I am seeing many tweets on twitter (obviously) talking about that “a rollback query on innodb does not reset the auto_increment counter”. I quickly went test it and really didn’t understand what happened with this user environment, due to it I decided [...]

Implicit COMMIT considered harmful.

If you execute the following, what does your RDBMS do?

CREATE TABLE t1 (a int);
START TRANSACTION;
INSERT INTO t1 (a) VALUES (1);
START TRANSACTION;
INSERT INTO t1 (a) VALUES (2);
ROLLBACK;
SELECT * FROM t1;

The answer may surprise you.

Benchmarking MySQL ACID performance with SysBench

A couple of question I get a lot from MySQL customers is “how will this hardware upgrade improve my transactions per second (TPS)” and “what level of TPS will MySQL perform on this hardware if I’m running ACID settings?” Running sysbench against MySQL with different values for per-thread and global memory buffer sizes, ACID settings, and other settings gives me concrete values to bring to the customer to show the impact that more RAM, faster CPUs, faster disks, or cnf changes have on the server. Here are some examples for a common question: “If I’m using full ACID settings vs non-ACID settings what performance am I going to get from this server?”

Let’s find out by running sysbench with the following settings (most are self explanatory – if not the man page can explain them):

  • sysbench –test=oltp –db-driver=mysql –oltp-table-size=1000000 –mysql-engine-trx=yes –oltp-test-mode=complex …
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Showing entries 1 to 9