I was at a client site with Yves Trudeau ( another MySQL consultant ) and the client had purchased a brand new top of the line 16 core server. It is well documented in many places that scalability beyond 4-8 cores with innodb is less then optimal. We were asked for a ballpark on the performance of a 16 cores vs an 8 cores, and specifically if their were any options to reduce the number of cores the mysqld process could use. We decided to benchmark this using DBT2. To do the test we ended up setting the CPU affinity of the mysqld process. You can set this with the following command: taskset. Yves ended up trying the same DBT2 tests for 1-16 cores. I won’t write too much about the scalability here, as I said their are way better resources out their that can explain it better, but what I wanted to do is post the results of …
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The MySQL community is mobilizing to help a 2 year old boy who is at grave risk of dying. The son of Andrii Nikitin, MySQL Support engineer, needs a bone marrow transplant to survive. Online donations are the fastest way of helping this unfortunate kid. His father is doing whatever it takes to help his son, including mortgaging or selling his possessions, but that may not be enough. Everybody's help is necessary to give this boy a chance. Last Saturday my accountant gave me the unpleasant news that I have to pay the IRS a large sum of money. Nothing you can do with taxes, unless you are a crook. My … |
The Sphinx project just released version 0.9.8, with many enhancements since the previous release. There’s never been a better time to try it out. It’s really cool technology. What is Sphinx? Glad you asked. It’s fast, efficient, scalable, relevant full-text searching and a heck of a lot more. In fact, Sphinx complements MySQL for a lot of non-search queries that MySQL frankly isn’t very good at, including WHERE clauses on low-selectivity columns, ORDER BY with a LIMIT and OFFSET, and GROUP BY.
Apparently High Performance MySQL, 2nd Edition is selling quite well – I’m not sure exactly how well – because we’re preparing for a second printing. This makes me very happy. I don’t think they anticipated going back to the press for quite some time. The book fluctuates between sales rank 1000 and 2000 on Amazon during the day, and has reached as high as 600 or so. This is just phenomenal.
Let's assume you have a 512MB table, and you decide to alter the
table to add an index to make queries faster.
How long would you expect this alter to take? Hours? Days?
Even with 7200 RPM-slow disks the alter should of finished in
less then 1/2 hour.
I ran across an alter that was running for 4 days-on 512MB
datasize. The reason why it ran so long is because there was a
SELECT that was running preventing mySQL from performing "rename
table", the last leg of the ALTER TABLE process.
Killing that SELECT released the shared lock allowing the alter
to finish.
Do not KILL THE ALTER when stuck in this SHARED LOCK STATE; Do
NOT then remove the temporary tablespace file
"#sql-320f_106f99a2.*".
What will happen if you do remove the #sql* file by hand?
Well for one INNODB will crash the mysql instance saying it could
not find the temporary table …
My new edition of the MySQL 5.1 Cluster DBA Certification Study
Guide arrived today. It features a bigger format,
corrections, and much better graphics. And it is $10 less
expensive.
The MySQL Cluster is just different enough from the 'old
fashioned' server to be confusing to long time MySQL DBAs. This
book points out common problems people have getting their
clusters configured. So if you are curious about how clusters
work and want more than the man pages as a reference, order you
copy today!
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The MySQL community is united for a noble purpose. Leaving aside their usual differences about release cycles and openness philosophy, the community is united in helping the son of Andrii Nikitin, a MySQL Support engineer, to overcome the difficult challenge of financing a life saver bone marrow transplant. The MySQL project has made its e-commerce site available to help raising the funds as quickly as possible. A very young life is in danger, and many people from inside and outside the company have donated for Ivan. |
This is not the first case of open source and life saving tied together. For example, Matthew Swift, one of the …
[Read more]Andrii Nikitin and son
(Credit: Zack Urlocker)
MySQL has been very good to the open-source world. In turn, I'd like to see if we can give something back.
Andrii Nikitin is one of MySQL's support engineers based in Ukraine. As Zack Urlocker recently posted on his blog, however, Andrii has a major concern right now which has nothing to do with customer support:
Andrii's son Ivan, who is 2 1/2, is in need of a bone marrow transplant operation. This will require going to a clinic in Europe that will not be covered by regular insurance. So Andrii has aksed to see if we could help raise funds. The cost is expected to be $150,000 - $250,000. A huge amount for an engineer from Ukraine to cover. But a small amount by many people could make a big difference.
Consistent with your interest and means, I'd encourage you to help …
[Read more]Very cool OSS project for tracking and recovering your lost or stolen laptop. It?s a project from the University of Washington. This app sounds like a great way to address the 12,000 laptops lost per week at US airports. The UW website states: "Adeona is the first Open Source system for tracking the location of your lost or stolen laptop that does not rely on a proprietary, central service. This means that you can install Adeona on your laptop and go ? there's no need to rely on a single third party. What's more, Adeona addresses a critical privacy goal... READ MORE