Personal blog of Yzmir Ramirez

Percona is glad to announce the release of Percona Server 5.5.13-20.4 on July 1st, 2011 (Downloads are available here and from the Percona Software Repositories).

Based on MySQL 5.5.13, Percona Server Percona Server 5.5.13-20.4 is now the current stable release in the 5.5 series. All of Percona’s software is open-source and free, all the details of the release can be found in the 5.5.13-20.4 milestone at Launchpad.

Improvements

SHM Buffer Pool has been replaced with LRU Dump/Restore

The ”SHM” buffer pool patch, which provided the ability to use a shared memory segment for the buffer pool to enable faster server restarts, has been removed. Instead, we recommend using the LRU Dump/Restore patch which provides similar improvements in restart performance.

Replacement is due to SHM buffer pool both being very invasive and not widely used. Improved restart times are better provided by the much safer LRU D/R patch which has the advantage of also persisting across machine restarts.

The configuration variables for my.cnf have been kept for compatibility and warnings will be printed for the deprecated options (innodb_buffer_pool_shm_key and innodb_buffer_pool_shm_checksum) if used.

Instructions for disabling the SHM buffer pool can be found here.

Instructions on setting up LRU dump/restore can be found here.

Bug Fixes

• On a high concurrency environment with compressed tables, users may experience crashes due to improper mutex handling inbuf_page_get_zip(). Bug Fix: #802348 (Y. Kinoshita).

• XtraDB crashed when importing big tables (e.g. 350G) using the Expand Table Import feature due to a timeout. Bug Fix: #684829 (Y. Kinoshita).

• Partitioning adaptive hash index may leave to a hangup of the server in some scenarios. Bug Fix: #791030 (Y. Kinoshita).

• Statistics gathering for each record’s update. Bug #791092 (Y. Kinoshita)

Other Changes

• Improvements and fixes on the Percona Server Test Suite: , #693415, #794849, #800035, #800559, #782391,#785566, #790199 (O. Tsarev, Y. Kinoshita, S. Smith).

• Improvements and fixes on platform-specific distribution: #737947

For more information, please see the following links:

• Downloads: Binary distributions, Percona Software Repositories

• Installation instructions

• Consulting, support, training, and custom development

• Release notes

• Documentation

• Developer discussion group

I have posted results for FusionIO 320GB MLC on our ssdperformanceblog.com blog.
To not duplicate content, there is link on original post:
http://www.ssdperformanceblog.com/2011/06/fusionio-320gb-mlc-random-write-performance/

Follow my twitter Follow @VadimTk
for further results.

I have posted results for Intel 320 SSD on our ssdperformanceblog.com blog.
To not duplicate content, there is link on original post:
http://www.ssdperformanceblog.com/2011/06/intel-320-ssd-random-write-performance/

Follow my twitter @VadimTk for further results.

On July 12th at 9 AM PST I will be giving a webinar about performance implications for Hibernate and Connector/J. If you cannot attend at this time, a recorded session will be available soon after the webinar.

MySQL is not only about LAMP, and a lot of people use it from Java apps. For some of those, Hibernate is the persistent framework of choice. This webinar will discuss the performance implications of using Hiberate to manage persistence with a MySQL backend, and also some more broad implications for Connector/J  that will apply for anyone using MySQL from Java.

Topics will include:
* Very brief overview of ORMs and Hibernate
* Fetch strategies
* Lazyness
* Manually written SQL
* Concurrency
* Concurrency-related config options for Connector/J

You may register here.