… cases your virtual disk is basically nothing more than a file on the host filesystem rather than an actual physical volume. So, in….67x the throughput of a single port. [Don’t try more than 2; the additional work that the kernel has to do… some tables from master to slave, and if so, how? A: Yes. There are a few of ways to do it. One…
Post: ZFS on Linux and MySQL
May 24, 2013 By 17 Comments
…located in two data centers, one with Solaris servers and the other one with Linux servers. The …to get better performance because we already had more than enough for our purpose and some ZFS features…to start the snapshot while holding a “flush tables with read lock” and the flush operation will…
Post: MySQL Query Patterns, Optimized - Webinar questions followup
June 3, 2013 By 2 Comments
… where optimizing a query automatically would be more costly than just running the query in a suboptimal… instead of “>” and be guaranteed to find exactly one match. But the tradeoff of this solution … table in the EXPLAIN seem like it was scanning more rows. But by avoiding the temporary table, …
Post: MySQL and the SSB - Part 2 - MyISAM vs InnoDB low concurrency
May 22, 2013 By Leave a Comment
… during the testing and found that InnoDB does more IO than MyISAM when the database is cold, but … is substantially faster than InnoDB both cold and hot. SSB Flight #4 There is one query in this …_logs=32 innodb_old_blocks_time=0 table_open_cache=2048 table_definition_cache=16384 innodb_flush_method=…
Post: Migrating between MySQL schemas with Percona Xtrabackup
June 10, 2013 By 2 Comments
… slow on larger schemas. One of the downsides to mysqldump is the need to scan the full tables and in turn, load… other issues) with SQL rather than needing to import from a remote server. This can allow for more targeted restores, easier comparison…’ > discard-ddl.sql SELECT CONCAT(‘ALTER TABLE `’, table_name, ‘` DISCARD TABLESPACE;’) AS _ddl FROM INFORMATION_SCHEMA.TABLES WHERE TABLE_SCHEMA=’orig’ AND ENGINE=’InnoDB…
Post: Percona MySQL University @Portland next Monday!
June 12, 2013 By Leave a Comment
…’re less than a week away from Percona MySQL University at Portland, Oregon…, June 17. The latest in a series of FREE one-day educational events, we are pleased to feature 10 …Command Line Tools – as well as go into more detail about using pt-table-checksum tool to verify replication integrity And …
Post: Understanding the maximum number of columns in a MySQL table
April 8, 2013 By 5 Comments
…. For example, if you had more than a certain number of fields, you were going to need more than one 80×24 screen to enter in…’ and ‘N’ will use less space in the FRM than if you had one with ‘Y’ and ‘N’ and the other with… folks, in MySQL 5.6 you can create a table with a few more columns in InnoDB! This led me on another…
Post: Follow these basics when migrating to Percona XtraDB Cluster for MySQL
May 1, 2013 By 10 Comments
… applied to the other nodes, that is if you have more than one PXC node. This is because before Galera can create writesets… May Lead to Inconsistencies and May Not Even Work! MyISAM tables are supported within Percona XtraDB Cluster, however, MyISAM has only… PRIMARY KEYS If you still have tables without PRIMARY KEYs, then its time to make one for them. Galera does not work…
Post: Is Synchronous Replication right for your app?
May 14, 2013 By 18 Comments
…replication master] you can’t commit (at all) more than once per RTT. Applied to a Galera …These are maintained in separate tables and there also exists a users_groups table to define the relationship between …. batch writes Instead of updating global counters one at a time (from Example 1, above), …
Post: Galera Flow Control in Percona XtraDB Cluster for MySQL
May 2, 2013 By 5 Comments
…PXC) for MySQL. I actually had more material than I covered (by design), but one thing I regret we didn’…. Despite its name, this setting really does no more than to change if the fc_limit is dynamically … into the certification index, which is a hash table. A small fc_limit does however keep the …
