As far as I know there isn't a well accepted set of best
practices for MySQL, but there are many best practices known and
used by most MySQL DBA's. One of those best practices is that the
datadir must not be equal to a mountpoint; it has to be a
subdirectory of a mountpoint. I learned this the hard way a few
years ago when I used a NetApp Filer via NFS as a data directory.
The NetApp filer exposed the snapshots via a .snapshot directory.
A database in MySQL is a directory, so MySQL thought that the
.snapshot directory was a database. This resulted in some issues
with our monitoring scripts, so we had to create a mysql_data
directory and move all the databases to that directory.
For other setups directories like lost+found, .zfs, etc. gave
similar issues.
In MySQL 5.6 a new feature was introduced to make it possible to
make some databases hidden. To do this a ignore-db-dir option
needs to be specified for each directory. …
Some of you know that I have published how to install Oracle VM Manager (OVMM) on a Dom0 host since Oracle released the Oracle VM 3. I have described why you possibly may want to do it in my very first post. Just want to mention here that it should be used for sandbox configurations only. You can find the previous post on how to install 3.1.1 OVMM version under Dom0 here. This time I talk about 3.2.2 version.
NOTE: At the time of writing ORACLE VM 3.2.3 SERVER (Patch 16410428) and ORACLE VM 3.2.3 MANAGER (Patch 16410417) became available. I didn’t have time to install the latest versions yet. However I do not expect that installation are significantly …
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Hi guys, i was reading the new query cache plugin
from Roland Bouman, now default in mariadb-5.5.31
This is a very old feature request at mysql (27 Oct 2006
12:31):
http://bugs.mysql.com/bug.php?id=23714
And recent mariadb (thanks Sergei reading my MDEV =) )
(2012-05-04 01:22)
https://mariadb.atlassian.net/browse/MDEV-249
Well this is a very nice piece of code...
Every time i google about "mysql performace", "mysql cache" etc
... i get something like this:
…
This week we talk about server and status variables relating to the performance schema and the ps_helper tool. Ear Candy is an sql_mode bug, and At the Movies is a performance_schema and ps_helper webinar.
Performance Schema Variables
MySQL 5.5 performance schema variables
MySQL 5.6 performance schema variables - many
options are auto-sized
SHOW GLOBAL VARIABLES LIKE 'performance_schema%';
Following are benchmark results comparing Tokutek TokuDB and Percona XtraDB at scale factor 10 on the Star Schema benchmark. I’m posting this on the Shard-Query blog because I am going to compare the performance of Shard-Query on the benchmark on these two engines. First, however, I think it is important to see how they perform in isolation without concurrency.
Because I am going to be testing Shard-Query, I have chosen to partition the “fact” table (lineorder) by month. I’ve attached the full DDL at the end of the post as well as the queries again for reference.
I want to note a few things about the results:
First and foremost, TokuDB was configured to use quicklz
compression (the default) and InnoDB compression was not used. No
tuning of TokuDB was performed, which means it will use up to 50%
of memory by default. Various InnoDB tuning options were set (see
the end of the post) but the most important is that the …
Part 1 -
Installing Holland Backup ManagerI spoke at Percona Live
Conference and Expo 2013 about backups. Part of the talk focussed
on the backup products in the ecosystem that will help you make a
backup of your MySQL data. This follow-up article touches on one
of the frameworks from my talk, the Holland Backup Manager. I was
able to have a chat with some of the guys on the Rackspace booth
about Holland and had some questions regarding features
answered.
Holland is a backup framework focussing mostly on MySQL backups
but it is pluggable so you can write add backup providers to
extend it to your own needs. Using the framework you're able to
configure and deploy backup jobs of varying scope to multiple
machines. The framework which was originally developed at
Rackspace, currently supports mysqldump, lvm, xtrabackup and
pgdump (Postgres) also sqllite. The latest version is …
Percona Server for MySQL version 5.5.31-30.3
Percona is glad to announce the release of Percona Server for MySQL 5.5.31-30.3 on May 24, 2013 (Downloads are available here and from the Percona Software Repositories). Based on MySQL 5.5.31, including all the bug fixes in it, Percona Server 5.5.31-30.3 is now the current stable release in the 5.5 series. All of Percona‘s …
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Can’t find what you want or need? Do you have a tip or trick to
share? Do you want to lament over a technical woe? If yes, then
blog and send it to us for the Log Buffer, just as this one
contains tips, tricks, and woes.
Oracle:
Fahd Mirza and Tanel Poder throw the spotlight on the v$cell_thread_history view with respect to the Exadata.
Mark W. Farnham‘s rightsizing goes on with a roar, as he declares that he is pretty much a green sneaker, tree …
[Read more]I am currently working with a large customer and I am involved with servers located in two data centers, one with Solaris servers and the other one with Linux servers. The Solaris side is cleverly setup using zones and ZFS and this provides a very low virtualization overhead. I learned quite a lot about these technologies while looking at this, thanks to Corey Mosher.
On the Linux side, we recently deployed a pair on servers for backup purpose, boxes with 64 300GB SAS drives, 3 raid controllers and 192GB of RAM. These servers will run a few slave instances each of production database servers and will perform the backups. The write load is not excessive so a single server can easily handle the write load of all the MySQL instances. The original idea was to configure them with raid-10 + LVM, making sure to …
[Read more]Drupal is one of the most popular Content Management Systems (CMS) and is used increasingly in high-visibility sites, such as www.whitehouse.gov. This has brought a lot of attention on how to get the most performance out of Drupal and how to improve the availability of such sites. In this blog series I'll take you through the basics and on through to designing your own HA Drupal site.
But first, we need to understand what the challenges are in getting Drupal (or indeed any CMS) working on multiple servers in such a way as to ensure high availability and performance.