by Peter Zaitsev | Jul 25, 2007 | Benchmarks
Listening to Josh Berkus presentation on OSCON today I decided to take a closer look at SpecJAppServer benchmarks results which were published by PostgreSQL recently and which as Josh Puts it “This publication shows that a properly tuned PostgreSQL is not only...
by Peter Zaitsev | Jul 24, 2007 | Insight for DBAs
Looking for documentation for read_rnd_buffer_size you would find descriptions such as “The read_rnd_buffer_size is used after a sort, when reading rows in sorted order. If you use many queries with ORDER BY, upping this can improve performance” which is...
by Peter Zaitsev | Jul 23, 2007 | Insight for Developers
I’ve already wrote a few times about various projects using Sphinx with MySQL for scalable Full Text Search applications. For example on BoardReader we’re using this combination to build search against over 1 billion of forum posts totaling over 1.5TB of...
by Maciej Dobrzanski | Jul 18, 2007 | Percona Software
Microslow patch has been there for some time, but only for earlier MySQL editions such as 4.1 and 5.0. Now it’s also available for the latest 5.1. Because MySQL went through a lot of internal changes, the patch had to be written from scratch. It introduces some...
by Peter Zaitsev | Jul 18, 2007 | Insight for DBAs
In my previous post I was a bit wrong giving Innodb some properties it does not have. In fact Innodb does not currently sort pages in their position order flushing them to disk. Pages to be flushed are instead identified by other means – LRU and pages which...
by Peter Zaitsev | Jul 17, 2007 | Insight for DBAs
How does Buffer Pool size affects Innodb Performance ? I always expected the effect to be positive, Innodb with large buffer pool to performing better. Including Recovery of course. I even blogged about it. It turns out it is not always the case. Last week I was...
by Peter Zaitsev | Jul 10, 2007 | Percona Events
Last time I was in Silicon Valley in April after MySQL Users Conference, this time I’m planning to spend July 30 – August 2nd in Silicon Valley after OSCON visiting friends and customers. If you’re located in Silicon Valley or San Francisco area and...
by Peter Zaitsev | Jul 9, 2007 | Percona Events
Let me announce ClickAider – another projects we were working on in stealth mode for last several Months. ClickAider is Hosted Web Statistics system but it tracks Clicks rather than page views as most web counters do. And by clicks I mean not just clicks on the...
by Peter Zaitsev | Jul 8, 2007 | Insight for DBAs
In my previous post I mentioned you might need to increase net_write_timeout to avoid connection being aborted and now I think I should have better explained that. MySQL uses a lot of different timeout variables at different stages. For example when connection is just...
by Peter Zaitsev | Jul 6, 2007 | Insight for Developers
We’re working with web site preparing for massive growth. To make sure it handles large data sets as part of the process we work on generation test database of significant size as testing your application on table with 1000 rows may well give you very dangerous...
by Peter Zaitsev | Jul 5, 2007 | Insight for Developers
What does working with large data sets in mySQL teach you ? Of course you have to learn a lot about query optimization, art of building summary tables and tricks of executing queries exactly as you want. I already wrote about development and configuration side of the...
by Peter Zaitsev | Jul 4, 2007 | Insight for DBAs
I’ve read through Top 5 (or more) wishes posted by number of MySQL employees as well as by a lot of community members. It was great to see so wide coverage as people with different backgrounds wish different things – Developers have some wishes to ease...
by Peter Zaitsev | Jul 3, 2007 | Percona Events
Vadim and me will be speaking on OSCON 2007, taking place in Portland,OR July 23-27. Our talk will be about Open Source Transactional Storage Engines meaning Innodb, Falcon, Solid and PBXT. We’ll look into architecture of these storage engines as well as compare...
by Peter Zaitsev | Jul 1, 2007 | Insight for Developers
On many web sites you would see a counter how many time given object – blog post, forum thread, image, movie etc was viewed. This is sometimes handy feature but it can be rather expensive from performance point of view. The nasty thing with counters as they are...
by Peter Zaitsev | Jun 29, 2007 | Insight for DBAs
About a week ago Marten send me email pointing to his article published on Jays Blog (Come on Marten, it is time for you to get your own blog). I should have replied much earlier but only found time to do that now. So here is my list 1. Be Pluggable Unlike many...
by Peter Zaitsev | Jun 26, 2007 | Insight for DBAs
I ran into pretty interesting behavior today. We needed to dump and reload large database and we had pretty good IO subsystem so we started number of mysqldump processes in parallel. Unlike in other case when we did load in parallel, dump in parallel did not increase...
by Peter Zaitsev | Jun 25, 2007 | Insight for DBAs
One may think one may use MySQL Slow query log to log all slow queries to catch problematic queries or for audit purposes. In fact however not all the queries are logged. I already mentioned mysql slave queries are not logged to slow query log and it looks like I was...
by Peter Zaitsev | Jun 18, 2007 | Insight for Developers
I prefer to use Integers for joins whenever possible and today I worked with client which used character keys, in my opinion without a big need. I told them this is suboptimal but was challenged with rightful question about the difference. I did not know so I decided...
by Peter Zaitsev | Jun 16, 2007 | Insight for Developers
Just found this little handy feature today: mysql> insert into c select rand()*1000, sha1(rand()) from c; Query aborted by Ctrl+C ERROR 1317 (70100): Query execution was interrupted 123 mysql> insert into c select rand()*1000, sha1(rand()) from c;Query aborted...
by Peter Zaitsev | Jun 16, 2007 | Insight for DBAs
I filed the following bug today. Basically it looks like in certain conditions Innodb may be started twice in the parallel on the same data files which can hurt database badly. It is true it does not seems to be 100% repeatable but I’ve seen it multiple times in...
