… affects both response time and throughput – The transaction log. The InnoDB transaction log handles REDO logging, this is the mechanism that provides the A (Atomic… does this affect throughput? As the REDO log in InnoDB uses a fixed length circular transaction log, the speed at which you can process…
Post: Analyzing the distribution of InnoDB log file writes
July 16, 2010 By 5 Comments
… statistics about how the log file writes are distributed in terms of write size. InnoDB writes to the log files in multiples of… 4k. This server has innodb_flush_log_at_trx_commit set to 2. This means each transaction does a log file write, the…, the distribution is a simple observation to make, but the InnoDB redo log system is intricate. It’s not something to guess about…
Post: Choosing proper innodb_log_file_size
July 3, 2006 By 12 Comments
… recovery and why large innodb_log_file_size slows down recovery. During startup after crash Innodb scans log files to find log records which only have been applied in memory and do not exist in tablespace. Log records… proportional to size of log files, so expect 1GB logs to take twice time to apply compared to 512MB logs. Redo phase is however…
Post: The relationship between Innodb Log checkpointing and dirty Buffer pool pages
February 17, 2012 By 5 Comments
… know that writing into Innodb updates buffer pool pages in memory and records page operations in the transaction (redo) log. Behind the scenes those updated (dirty) buffer pool pages are flushed down the to the tablespace. If Innodb stops (read… database. Recovery uses the transaction log by redoing (hence the name ‘redo log‘) the page operations in the log that had not already been flushed…
Post: How to estimate time it takes Innodb to Recover ?
May 9, 2007 By 7 Comments
… how Innodb recovery works. When Innodb recovers from logs it finds the last checkpoint time. Innodb has fuzzy checkpointing and yet there is particular log… of log files as Innodb needs to flush database pages to the tablespace before it can overwrite matching log records in the log file… increase recovery time even more I hope Heikki will enable redo and undo phases to be performed in the parallel, which…
Comment: Percona Server 5.5.15 + Galera 21.1-beta2
October 4, 2011 By 18 Comments
…’s still good, but it apparently aggravates the issues with InnoDB redo log flushing, which Vadim has recently blogged about.
Post: Bug#12704861
November 20, 2011 By 1 Comment
…’ll repeat here the full documentation from the release notes: “InnoDB Storage Engine: Data from BLOB columns could be lost if… redo log about the BLOB page writes, and only after that write the redo log about the B-tree changes. The buggy fix would log… redo log about the BLOB page writes, and only after that write the redo log about the B-tree changes. The buggy fix would log…
Comment: Disaster: MySQL 5.5 Flushing
September 19, 2011 By 27 Comments
… compare: NDB has database in memory. InnoDB has buffer pool in memory. NDB writes REDO log. InnoDB does too. NDB has a background thread…-time database and InnoDB is not. InnoDB is more newbie friendly because you don’t see the problem 
When NDB redo log file is… of the redo log file and start from the beginning again (I think it actually is a circular buffer). When InnoDB log file is…
Comment: Innodb Double Write
March 31, 2011 By 23 Comments
… in the log should be redo when doing recovery? I think even the page is “partial written”, it doesn’t matter, redo log know… the redo log. Unless you mean “partial write” will modify someting not saved in the redo log?? I mean, EVERY change are in the redo log… think I still didn’t understand innoDB , why it need “double write”? I am new to innoDB, not knowing any internal details…
Comment: Innodb Double Write
August 4, 2006 By 23 Comments
… in the log should be redo when doing recovery? I think even the page is “partial written”, it doesn’t matter, redo log know… the redo log. Unless you mean “partial write” will modify someting not saved in the redo log?? I mean, EVERY change are in the redo log… think I still didn’t understand innoDB , why it need “double write”? I am new to innoDB, not knowing any internal details…
