… not so much the waiting, you could simply send all your writes to one node. This should… is not safe to retry after the database state changes. retry deadlocks Now we start to get … 1, NOW()); Conclusion Choosing a system to replicate your data to a distributed system requires tradeoffs. Most of…
Post: SHOW INNODB STATUS walk through
July 17, 2006 By 40 Comments
… 0 MySQL thread id 8079, query id 728899 localhost root Sending data select sql_calc_found_rows * from b limit 5 Trx… 0 MySQL thread id 8078, query id 728898 localhost root Sending data select sql_calc_found_rows * from b limit 5 Trx…, checkpointing, purging, flusing logs, doing insert buffer merge. Values for “state” field are rather self explanatory. You can also see number…
Post: Implications of Metadata Locking Changes in MySQL 5.5
February 1, 2013 By 9 Comments
… | | preparing | 0.000006 | | executing | 0.000001 | | Sorting result | 0.000002 | | Sending data | 0.000040 | | end | 0.000003 | | query end | 0.000002 | | closing… spent nearly all its time waiting in the “Opening tables” state. Now this behavior with respect to ALTER making the table… | | preparing | 0.000006 | | executing | 0.000001 | | Sorting result | 0.000004 | | Sending data | 0.000033 | | end | 0.000003 | | query end | 0.000002 | | closing…
Post: Write contentions on the query cache
September 5, 2012 By 5 Comments
… | 0.000002 | | Sending data | 0.003407 | | Waiting for query cache lock | 0.000003 | | Waiting on query cache mutex | 0.000003 | | Sending data | 0.003515…answer is in the way the query cache works. Simply stated, the server wants to lock the query cache both …
Post: MySQL 5.6 vs MySQL 5.5 and the Star Schema Benchmark
March 11, 2013 By 7 Comments
…state = p2.state order by p1.duration desc; +—–+———————-+———–+———-+———–+———–+——-+——-+————–+————–+——-+——-+ | seq | state… | 12 | Sending data | 33….
Post: How FLUSH TABLES WITH READ LOCK works with Innodb Tables
March 23, 2012 By 20 Comments
… Time | State | Info | Rows_sent | Rows_examined | Rows_read | +——-+——+———–+———-+————+——+——————————+——————————+———–+—————+———–+ | 10219 | root | localhost | dumptest | Query | 688 | Sending data | select…
Post: The perils of InnoDB with Debian and startup scripts
January 28, 2009 By 13 Comments
… | User | State | Info +——+——————+—————-+————- | 7 | debian-sys-maint | NULL | CHECK TABLE tableA… | 739 | user | | NULL | 4776 | user | | NULL | 6318 | user | Sending data | insert into… | 6356 | user | statistics | select … | 6357 | user | statistics | select … | 6358 | user | Sending data | select … | 6359 | user | statistics | select … | 6360 | user | | NULL | 6361 | user…
Post: How fast is FLUSH TABLES WITH READ LOCK?
April 24, 2010 By 30 Comments
… | Id | User | Host | db | Command | Time | State | Info | +—-+——+———–+——+————+——+——————-+———————————————————————-+ | 4 | root | localhost | test | Query | 80 | Sending data | select count(*) from t t1 join t…
Post: How to convert MySQL's SHOW PROFILES into a real profile
February 20, 2012 By 12 Comments
… WHERE QUERY_ID = @query_id GROUP BY STATE ORDER BY Total_R DESC; +———————-+———-+——-+——-+————–+ | STATE | Total_R | Pct_R | Calls | R/…to tmp table | 0.046175 | 26.74 | 1 | 0.0461750000 | | Sending data | 0.018478 | 10.70 | 3 | 0.0061593333 | | Sorting result | …
Post: Percona XtraDB Cluster: Failure Scenarios with only 2 nodes
July 25, 2012 By 6 Comments
… [ERROR] WSREP: Local state seqno (6) is greater than group seqno (5): states diverged. Aborting to avoid potential data loss. Remove ‘/var/lib…:51.273 INFO: STATE EXCHANGE: Waiting for state UUID. 2012-07-24 11:42:51.276 INFO: STATE EXCHANGE: sent state msg: f00ff3f4-d573… (TO: 19) 2012-07-24 11:42:51.292 INFO: Sending state transfer request: ‘trivial’, size: 7 2012-07-24 11:42…
