I found time to continue my previous work on group commit for the binary log in MariaDB.
In current code, a (group) commit to InnoDB does not less than
three fsync() calls:
Yesterday I was asked by a customer for the reason why he had
failed to achieve scale with a state-of-the-art "shared-storage"
cluster. "It's a scale-out to 4 servers, but with a shared disk.
And I got, after tons of work and efforts, 130% throughput,
not even close to the expected 400%" he said.
Well, scale-out cannot be achieved with a shared storage and the
word "shared" is the key. Scale-out is done with
absolutely nothing shared or a "shared-nothing"
architecture. This what makes it linear and
unlimited. Any shared resource, creates a tremendous burden
on each and every database server in the cluster.
In a previous post, I identified database engine
activities such as buffer management, locking, thread
locks/semaphores, and recovery tasks - as the main bottleneck in
the OLTP …
Today, I think we witnessed a small sign for a big
revolution...
http://www.pcworld.com/businesscenter/article/256383/dell_reaches_for_the_cloud_with_new_prototype_arm_server.html
"Dell announced a prototype low-power server with ARM processors,
following a growing demand by Web companies for custom-built
servers that can scale performance while reducing financial
overhead on data centers"In short, ARM (see Wikipedia definition
here) is an architecture standard for processors.
ARM processors are slower compared to good old x86 processors
from Intel and AMD, but have power-efficiency, density and price
attributes that intrigue customers, especially in our days of
green data centers where carbon emissions is …
1. Percona Toolkit
Percona Toolkit (aka Maatkit and Aspersa) is must have collection
of advanced command-line tools which helps in performing tasks
that are too difficult or complex to perform manually.
2. Mydumper
Mydumper is a high-performance multi-threaded backup/restore tool
for MySQL. It’s up to 10x faster compared to mysqldump, can take
consistent snapshots and provides File compression on-the-fly.
Though it’s still under active development but is well
tested/used in production on some large installations.
3. MySQL Master HA
This tool helps to maintain your Master-Slave replication setup.
A primary objective is automating master fail-over and slave …
In Ausgabe 3/2012 der Fachzeitschrift JavaSPEKTRUM wurde kürzlich ein Artikel mit dem Titel "SOA-basierte NoSQL-Lösung im Mobile-Umfeld" veröffentlicht, dessen Co-Autor ich bin. Er beschreibt, wie eine mobile Java-Applikation mittels kreativer Ansätze und einem Mix aus moderner und altbewährter Technik zum Erfolg gebracht wurde.
Der Volltext kann entweder im Browser auf der codecentric Homepage unter der Rubrik Kompetenzen/Publikationen gelesen werden, steht aber auch als PDF zum Download bereit.
Why demos?
For as long as I can remember in my public speaking activities, I have always planned my presentations with some sort of live demo in it. I am always surprised when a conference venue asks me to provide my slides in advance, to be loaded in an anonymous computer with no chance of demos. I always turn down such offers, as I always want to provide a demo.
There have been times when technical or time constraints prevented me from demoing something, and in these cases I felt that the presentation was lacking a vital part. But I always try. I have even given demos during lightning talks, and those were the ones that made me feel really good.
I have given hundreds of presentations, and hundreds of demos, and as in every human activity, I have made plenty of mistakes. I believe I have learned some valuable lesson from my mistakes, and this article is my attempt at sharing the joy with wannabe presenters and also with …
[Read more]Momentum for MySQL Utilities continues to build. I hosted a webinar recently about MySQL Utilities (available on-demand from the link below), which generated a lot of interest and some good questions.
With so many questions and ideas coming in I decided to create a blog of FAQs. I plan to add these to the MySQL documentation as well. Keep your ideas and questions coming!
I hope you find these questions enlightening. I have grouped them for easier reading. You can find the MySQL Utilities documentation using the link below.
…
[Read more]
The mysqldiff and mysqldbcompare utilities were designed to
produce a difference report for objects and in the case of
mysqldbcompare the data. Thus, you can compare two databases and
produce a report of the differences in both object definitions
and data rows.
While that may be very useful, would it not be much more useful
to have the ability to produce SQL commands to transform
databases? Wait no longer! The latest release of MySQL Utilities
has added the ability to generate SQL transformation statements
by both the mysqldiff and mysqldbcompare utilities.
To generate SQL transformations in either utility, simply use the
--sql option to tell the utility to produce the statements.
Object Transformations with mysqldiff
If you would like to compare the schema of two databases (the
objects and their definitions), mysqldiff can do that for you and
produce a difference report …
MongoDB Backup types and strategies are neatly explained in its documentation, which you can check here. In case you are not familiar with MongoDB backup types and strategies, please have a look at its documentation.
What I am describing here is a simple script which we are using since months to take MongoDB backup and transfer it over to our Backup server. Here are few things its doing:
Yesterday (4/19) I attended the AWS Summit in NYC (http://aws.amazon.com/aws-summit-2012/nyc).
I'm a big fan and also a heavy user of AWS especially S3, EC2,
and naturally, RDS. In every point in time I have several dozens
of AWS machines running for me out there in the East region, and
in some cases when we do some special benchmarks and tests,
number of EC2 and RDS machines can easily reach 3-digit. As I
said, I'm a fan...
A few quotes I was able to catch and document on my laptop, on my
laps...:
"When you develop an app for facebook, you must be prepared (and
be afraid) that to your party, not noone will show up, but
everybody will show up!" So true! Simple and true. We all want to
succeed, to have success with our app. We have to think about
scaling from day 1.
"Database was bottleneck for building of sophisticated apps. This
is …