… lot when a) the database’s working set is bigger than the server’s memory, or b) the workload is write… from these EBS volumes is — some are fast, some are slow, even though we are asking the same thing from all….1 4.5 0.1 0.0 4.6 4% 0 12.1 sdj1 0.5 0.1 4.4 0.0 0.0 1.8 3% 0 13.1 sdj1 0.7 5.1…
Comment: Disaster: LVM Performance in Snapshot Mode
February 9, 2009 By 55 Comments
…5 | 239.7 4.1 331.4 1207.4 81.3 | 60.7 10.0 335.7 1201.1 83.5 312.7 | 250.8 4.1…can have big consequences. Look at the slow start of ext3 – it took nearly … the exclusive rwlock for much longer than if it didn’t have to … of what MySQL is doing so we are currently testing xfs with MySQL. But …
Post: TPC-H Run on MySQL 5.1 and 6.0
April 10, 2008 By 16 Comments
…8 hard drives which this box had. MySQL Also was very slow running some queries so we changed scripts a…let us first take a look at MySQL 5.1.23 vs 6.0.4 results for 10GB data set which “…by MySQL 5.1 time so if it is less than 1 MySQL 6.0 is faster if more than 1 slower: Query MySQL 5.0.23 MySQL 6…
Post: MySQL 5.0, 5.1 and Innodb Plugin CPU Efficiency
December 3, 2008 By 15 Comments
…. MySQL 5.1 is 4% slower than MySQL 5.0 with two cores and just 2% slower with 8 cores, thus showing a bit better scalability. MySQL 5.1 plugin… you would not only run MySQL plugin but also use new “Barracuda” Innodb format you see just 1% slow down with 2 cores… error. This tells us there are some workloads when MySQL 5.1 is slower than 5.0, and same applies to the new Innodb code…
Post: Scaling problems still exist in MySQL 5.5 and Percona Server 5.5
May 20, 2011 By 11 Comments
MySQL 5.5 and Percona Server 5.5 do not… system I used for test was 4 socket r910 with X7542 CPUs giving… compared Percona Server 5.1.56-12.7 and Percona Server 5.5.11-20.2…can’t get use of more than 8 cores effectively (which would …hash_index,btr_search_info_update_slow,btr_search_info_update,btr_…
Post: Why MySQL could be slow with large tables ?
June 9, 2006 By 139 Comments
…or blogs you probably heard complains about MySQL being unable to handle more than 1.000.000 (or select any other…disk bound can be very slow. One of the reasons elevating this problem in MySQL is lack of advanced join…sec rate. So we would go from 5 minutes to almost 4 days if we need to do the join….
Post: Modeling MySQL Capacity by Measuring Resource Consumptions
March 8, 2011 By 1 Comment
…MySQL process: root@ubuntu:/var/log/mysql# cat /proc/19018/stat 19018 (mysqld) S 1 19018 19018 0 -1…slow_verbosity=full you can also get great amount of related data from mk-query-digest report: # Overall: 1…5.15k 3.88k 258.55k 1…1.57M 0 1 0.94 0.99 0.24 0.99 # Rows examine 4 1.57M 0 1… less than 1 row …
Post: More Gotchas with MySQL 5.0
July 27, 2007 By 23 Comments
… number of latched pages, which is quite slow with buffer pools containing millions of pages. … MySQL 5.0 compared to MySQL 4.1 It was something like 2-3 for MySQL 4.1 vs 40-60 for MySQL 5.0 At the same time however there were virtually no disk IO and CPU being loaded less than 20% (out of 4…
Post: Analyzing air traffic performance with InfoBright and MonetDB
October 2, 2009 By 50 Comments
…3.40GHz. InfoBright (ICE) version: 5.1.14-log build number… load statement is: mysql -S /tmp/mysql-ib.sock -e … with result: [ 5, 7509643 ] [ 1, 7478969 ] [ 4, 7453687 ] [ 3, 7412939 ] [ 2, 7370368 ] [ … Count of flights delayed more than 10min per day …range of rows, the slowness here is similar to Q0…
Post: Using CHAR keys for joins, how much is the overhead ?
June 18, 2007 By 18 Comments
…to benchmark. The results below are for MySQL 5.1.18 using MyISAM and Innodb tables. …default ? Joining on Char columns completes in 4.5 seconds on Innodb which is about 50…5 seconds which is just 20% slower than integer based join for Innodb. Finally I decided to check if using longer strings slows…
