… and newer, you can just watch Innodb_os_log_written from SHOW GLOBAL STATUS, too.) mysql> select (3838334638 – 3836410803) / 1024 / 1024 as… log file sizes in the gigabyte ranges. But that’s generally a mistake. The server I used for the measurements above is a big one doing a lot of work, not a toy. Log file sizes…
Post: MySQL 5.5.8 - in search of stability
January 3, 2011 By 11 Comments
… is too big, and now we again hit the limit set by innodb_log_file_size. The 15-minute average result for this test is…_capacity; but the limiting factor is still innodb_log_file_size. To prove it, I took Percona Server based on 5.5.8… it requires 10500MB for checkpoint age; that is, 14000MB of log space. And, the Percona Server result is ~2x better than the best result…
Post: The relationship between Innodb Log checkpointing and dirty Buffer pool pages
February 17, 2012 By 10 Comments
… Checkpoint is in a minute. If you use Percona server, it does the math for you by including some more output: — LOG — Log sequence number 9682004056 Log flushed up to… main reason this is important is if the Checkpoint Age is not a factor in dirty buffer flushing, it can get too big and cause…
Post: Percona Server vs MySQL on Intel 320 SSD
February 23, 2012 By 21 Comments
… do we solve it in Percona Server ? There is whole set of improvement we made, like: Big log files Tuned flushing algorithm Disable flushing… is a way to improve throughput in Percona Server: increase innodb_log_file_size. There are stability timeline for Percona Server with innodb_log_file… proper tuning, Percona Server/XtraDB outperforms MySQL, and provides a more stable throughput. Of course if a tuning is too hard to figure…
Post: How Percona does a MySQL Performance Audit
November 24, 2008 By 17 Comments
…’ll keep within just a MySQL server. The first step is to log into the machine via SSH and … what its status is. I can see the drive status, too. Sometimes a failed drive is present but no… figure out what is happening because it can indicate something else is wrong. This is not a big deal for …
Comment: Measuring the amount of writes in InnoDB redo logs
October 8, 2012 By 4 Comments
… the log space is used. The size needs to be big enough so that this isn’t reached even when the server is doing occasional… is useful to tune so they aren’t a lot bigger than required. But it’s better to err on the too big than too small side because too small tends to cause occasional outages or disruption if the server hits async flushing…
Post: High-Performance Click Analysis with MySQL
December 22, 2008 By 13 Comments
… Assuming that you will use the stock MySQL server, InnoDB is usually your best bet. (Actually, XtraDB might… Keep those big fat log files out of the database. The database is usually the most expensive…can also help you avoid massive tables that are too big to maintain. If you know you’ll get …
Comment: MySQL 5.5 and MySQL 5.6 default variable values differences
February 21, 2013 By 8 Comments
…/en/server-default-changes.html , see where we adjusted settings and try the settings for any OLTP workloads they have. back_log is… to be too big. In practice we tend to see query cache sizes that are far too big more than ones that are too small. Agree that bigger – up to a few tens of megabytes, maybe more rarely larger, is…
Post: Optimizing InnoDB for creating 30,000 tables (and nothing else)
December 22, 2011 By 5 Comments
…. This is perfect for running a test suite for a database server as if … FRM file to disk and set log flushing to happen as infrequently as …total of 14.5 minutes. Not too bad. This is less than my initial test with…execution time of 3 minutes. This is a big difference to the original 14.5 minutes…
Post: Helgrinding MySQL with InnoDB for Synchronisation Errors, Fun and Profit
November 24, 2011 By 2 Comments
…server developers. The Valgrind Memcheck tool, which is synonymous with Valgrind itself, is relatively widely used for the MySQL server development: there is…log_write_low asserts that it holds the log system mutex, and log…too…
