… anything you find in standard async MySQL replication. It is my belief that…any node by simply by running “FLUSH TABLES WITH READ LOCK”, or perhaps …purposes: It limits the amount of delay any node in the cluster …slaves with no writes coming from them. However, with multi-node writing, larger queues…
Post: MySQL and Percona Server in LinkBench benchmark
May 8, 2013 By 18 Comments
…pool_t*) 2.53% 1338484 mysqld mysqld [.] ut_delay(unsigned long) So basically most of the time…per_table innodb_read_io_threads = 8 innodb_write_io_threads = 8 innodb_io_capacity = 5000 sync…-innodb_flush_neighbors=0 loose-metadata_locks_hash_instances=256 innodb_buffer_pool_instances=16 # MySQL 5.5…
Post: Ultimate MySQL variable and status reference list
January 8, 2011 By 4 Comments
… referring to the amazing MySQL manual, especially the option and variable reference table. …_retry_countblogpercona.commanual net_write_timeoutblogpercona.commanual newblogpercona.commanual no_defaultsblogpercona.commanual Not_flushed_delayed_rowsblogpercona.commanual oldblogpercona.commanual…
Post: InnoDB Flushing: a lot of memory and slow disk
March 31, 2011 By 57 Comments
…flushing implementations (including both MySQL native adaptive flushing…delays the problem until later; 2) increases recovery time (and that is an important factor with slow disks); and 3) MySQL…flushing neighbor pages was implemented to perform sequential writes where possible and avoid random writes…
Post: Performance gotcha of MySQL memory tables
February 1, 2008 By 5 Comments
… know about comes from the fact it is the only MySQL storage engine which defaults to HASH index type by default… in Innodb Buffer Pool and log flush on transaction commit was also disabled, meaning Innodb could delay writes and do all the changes directly in memory. MyISAM however had to perform number of random writes to the…
Post: MySQL net_write_timeout vs wait_timeout and protocol notes
July 8, 2007 By 1 Comment
… rather typical for some applications to have long delays between queries. If query is being read or … flushes buffers to the disk every so often which can take long enough to trigger default net_write… increasing net_write_timeout ? Not what I know of. You can’t use something like mysql_ping because …
Post: Multiple purge threads in Percona Server 5.1.56 and MySQL 5.6.2
May 3, 2011 By 13 Comments
…size=1900M innodb_flush_log_at_trx_commit=2 innodb_doublewrite=1 innodb_flush_method=…penalize further TPS. MySQL 5.6.2 Results Now let’s test MySQL 5.6.2…fact, as of the time of this writing, the code is already different in the … short sleeps and apparently those sleep delays are too long, so let’s …
Post: Why delayed flushing can result in less work
December 9, 2009 By 5 Comments
… another page flush results. If the first flush had been delayed, the two flushes could have been done as one flush. This is called write combining. In some workloads, the same rows could be updated many, many times — so delaying and permitting write… there is a side effect such as mutex contention inside MySQL or InnoDB. So whether this matters for you is workload…
Comment: MySQL Server Memory Usage
September 1, 2006 By 21 Comments
…’, ’4001′ ‘Created_tmp_tables’, ’669137′ ‘Delayed_errors’, ’0′ ‘Delayed_insert_threads’, ’0′ ‘Delayed_writes‘, ’0′ ‘Flush_commands’, ’5′ ‘Handler_commit’, ’19092941′ ‘…mysql.sock pid-file=/var/run/mysql/mysql.pid datadir=/db/disk2/mysql/data log-bin=/var/log/mysql/log log-slow-queries=/var/log/mysql…
Post: MySQL Server Variables - SQL layer or Storage Engine specific.
June 8, 2006 By 14 Comments
…memory tables. So first MySQL versions did not …write Delay updating indexes for MyISAM tables. Good for performance but tables will be badly corrupted on crash. delayed_insert_limit, delayed_insert_timeout, delayed…flush, flush_time Flushing (closing) of tables after query is complete or every flush…
