…Config 3: MySQL 5.5 and 5.6 with a 4G buffer pool instead of the default 128M Rationale: Since O_DIRECT is not used by default, the file system cache will give better…Using where 2 rows in set (0.00 sec) mysql> select * from information_schema.global_status where variable_…
Post: Shard-Query adds parallelism to queries
November 15, 2010 By 18 Comments
… the recent optimizations to MySQL still leave a lot of low hanging fruit where these are concerned. This is particularly true for OLAP… much improvement could be made to MySQL so that is could better utilize all available resources (that is, scale better) when running small…, it takes a list of queries in a file (or stdin) and a config file. It runs the SQL via ShardQuery and it…
Post: How to replace a NDB node on EC2
June 9, 2011 By 10 Comments
…, where a node can disappear almost without notice, one would think that it is a good fit. It is… instead of IPs in the config.ini file. What needs to be done is to define, in /etc/hosts, … like: [NDBD DEFAULT] NoOfReplicas=2 Datadir=/var/lib/mysql-cluster/ DataMemory=1G IndexMemory=100M [NDB_MGMD] Id…
Comment: How to estimate time it takes Innodb to Recover ?
June 25, 2008 By 7 Comments
…5b 6b 7b 8b 9b 10b -> where 10b is master of 1a mysql> show master status; +————+———-+——————————————-+——————+ | File | Position | Binlog_Do_DB | …x86_64 x86_64 GNU/Linux Also currently: these config (my.cnf) were all disabled from 20 servers: # …
Post: Shard-Query EC2 images available
May 11, 2011 By 2 Comments
… >> /dev/null 2>&1 < /dev/null done; Where to find the images Amazon…InnoDB data directory size is 42GB, which is twice the original size … 1988 to 2010′; mysql> use ontime1; Database changed mysql> show table status like …file for testing an cluster of 1 to 20 nodes. cd shard-query #generate a config…
Post: MySQL 5.5.8 and Percona Server on Fast Flash card (Virident tachIOn)
December 21, 2010 By 11 Comments
… innodb_log_files located on separate RAID10 partitions, InnoDB datafiles on the Virident tachIOn 400G card The raw results, config, and script…: MySQL 5.5.8 – 78,091 NOTPM, Percona Server – 109,631 NOTPM, advantage: 1.4x This is actually the first case where I’ve seen NOTPM greater than 100,000 for a tpcc-mysql workload with 1000W…
Post: Percona XtraDB Cluster: Failure Scenarios with only 2 nodes
July 25, 2012 By 6 Comments
…where the majority is not reached. The quorum algorithm helps to select a PC and guarantees that there is…is greater than group seqno (5): states diverged. Aborting to avoid potential data loss. Remove ‘/var/lib/mysql//grastate.dat’ file…11:42:50.237 INFO: Read config: daemon: 0 address: gcomm://192….
Post: TMP_TABLE_SIZE and MAX_HEAP_TABLE_SIZE
January 19, 2007 By 17 Comments
… to have implicit temporary tables created in memory where possible, do to it you should increase tmp… Wrong. In fact setting tmp_table_size is not enough as MySQL also looks at max_heap_table_size… what users know about it, what is documented in the manual, config files, tons of books and articles on…
Comment: Solving RPM installation conflicts in CentOS 5 and CentOS 6
February 21, 2013 By 6 Comments
…var/lib/mysql//galera.cache’. 130221 17:59:05 [Note] WSREP: Passing config to GCS: …since we have already crashed, something is definitely wrong and this may fail…the following information to find out where mysqld died. If you see no…mysqld_safe mysqld from pid file /var/lib/mysql/mysql1.pid ended can …
Comment: Innodb Performance Optimization Basics
March 28, 2012 By 75 Comments
… = innodb_data_file_path = ibdata1:10M:autoextend innodb_log_group_home_dir = /usr/local/mysql/data innodb_buffer_… records is taking too long and all my transactions are locked. select count(1),field1 from Table where…Please help to improve performance and suggest if any config changes are to be made…
