XtraDB storage engine release 1.0.2-3 (Spring edition) codename Sapporo

Today we announce release 1.0.2-3 of our XtraDB storage engine.

Here is a list of enhancements:

• Move to MySQL 5.1.31
• Scalability fix — ability to use several rollback segments

Increasing the number of rseg may be helpful for CPU scale of write-intentional workloads. See benchmark results.

• Scalability fix — replaced page_hash mutex to page_hash read-write lock. See benchmark results.
• Fix broken group commit in InnoDB

As you know, the group commit of InnoDB doesn’t work after MySQL 5.0 with binlog.
We pretend to fix this and added “innodb_enable_unsafe_group_commit=[0|1]” parameter. Note if you set this parameter to “1” record order of binlog and InnoDB transaction log could be not same. But because InnoDB manages transactions in correct order most users may not have problem with this.

• New parameters in the XtraDB io patches:

  • innodb_ibuf_max_size — Restrict innodb-insert-buffer size
  • innodb_ibuf_active_contract — Enabling it makes the each user threads positive to contract the insert buffer as possible in asynchronous
  • innodb_ibuf_accel_rate — This parameter is additional tuning the amount of insert buffer processing by background thread.
  • innodb_flush_neighbor_pages — When you use the storage which don’t have “head seek latency” (e.g. SSD or enough Write-Buffered), 0 may show better performance.

• Changed parameter for control read ahead activity. Now it accepts string values:

  • innodb_read_ahead = [none|random|linear|both]

• Deb builds for Ubuntu

Percona XtraDB 1.0.2-3 (Sapporo) available in source and several binary packages.

XtraDB is compatible with existing InnoDB tables (unless you used innodb_extra_undoslots) and we are going to keep compatibility in further releases. We are open for features requests for new engine and ready to accept community patches. You can monitor Percona’s current tasks and further plans on the Percona XtraDB Launchpad project. You can also request features and report bugs there. Also we have setup two maillists for General discussions and for Development related questions.