…mysql –mysql-host=localhost –mysql-table-engine=innodb –mysql-db=test –oltp-table-name=md_cache_test_small –oltp-table-size=1100000 –mysql-user=msandbox –mysql… pool with only 12MB remaining. This makes workload extremely IO bound hence such drop in performance. The performance of mysqldump …
Post: What MySQL buffer cache hit rate should you target
June 29, 2006 By 5 Comments
… not just once. This means if you would have completely IO bound full table scan and you have 100 rows per page… to look at the number of misses – number of IOs which MySQL needs to do. You better to look at global and… issuing 100+ random IO requests which are not cached by OS or SAN this is likely to be IO bound problem. Yes this…
Post: State of MySQL Market and will Replication live ?
April 9, 2008 By 29 Comments
… see as response to these requirements ? From MySQL side we have further development of MySQL Cluster to be more usable for web… which can be used with MySQL to get very fast IO and so consolidate system suffering from IO bound workloads. There is KickFire appliance around the corner which more focuses on CPU bound…
Post: MySQL Users Conference - Innodb
May 9, 2007 By 6 Comments
… them physically sorted so they should be much faster for IO Bound Index scans and large range scans. We surely should benchmark… so it is still important. IO Scalability patches Mark Callaghan from Google released so many MySQL patches so we can call patched… they are far from optimal for server grade IO subsystems. These are for MySQL 4.0 at this point but we hope…
Post: InnoDB compression woes
May 20, 2011 By 14 Comments
…=16 –max-requests=0 –rand-type=uniform –max-time=1800 –mysql-user=root –report-interval=10 run this will report us… is 150x difference. As workload is clear read-only CPU bound, let’s check CPU stats: regular tables: —–cpu—— us sy…_list_mutex. I should check how compressed tables perform in IO-bound workload (this is where they should give main benefit), but…
Post: MySQL Partitioning - can save you or kill you
December 11, 2010 By 45 Comments
I wanted for a while to write about using MySQL Partitioning for Performance Optimization and I just got a relevant … in buffer pool completely so replication became CPU bound (single thread) instead of IO bound. You could celebrate but hey…. you need to… contain the value but many of them will require physical IO and going down to the leaf key to verify such…
Post: How network can impact MySQL Operations ?
September 1, 2008 By 5 Comments
… window which involved a lot of data copying around between MySQL boxes. We had prepared well and had measured how fast… overly fragmented tablespace, or it is easy to become IO bound rather than network bound. As I mentioned you can get even better… speed about 20MB/sec instead of projected 80MB/sec. The IO and CPU usage both on source and target servers was…
Post: TPC-H Run on MySQL 5.1 and 6.0
April 10, 2008 By 16 Comments
… tested 10G and 100G data sets which was CPU bound and IO bound box on the Dell 2950 box w 16G of RAM… is faster if more than 1 slower: Query MySQL 5.0.23 MySQL 6.0.4Ratio Query1370.50372.161.00 Query2724.63623… to 3 hours to give MySQL more time to complete the queries: Query MySQL 5.0.23 MySQL 6.0.4Ratio Query13784.453737…
Post: Profiling MySQL Memory Usage With Valgrind Massif
January 9, 2013 By 3 Comments
…. If you prefer to use another location (and are therefore bound to set proper file rights etc.) use: $ touch /your_location…::read_log_event(st_io_cache*, st_mysql_mutex*, Format_description_log_event const*) (in /usr/local/percona/mysql-5.5.28/usr…::read_log_event(st_io_cache*, st_mysql_mutex*, Format_description_log_event const*) (in /usr/local/percona/mysql-5.5.28/usr…
Post: MySQL: what read_buffer_size value is optimal ?
September 17, 2007 By 25 Comments
… check things out I’ve created table with simple structure: mysql> show create table dt2 \G *************************** 1. row *************************** Table: dt2 Create… rows to reach 4G in size so workload will be IO bound on the box with 2GB of memory. The was running…, with 3 runs and averaged results. MySQL 5.1.21-beta was used for tests. mysql> select count(*) from dt2 where slack…
