Documentation Home
MySQL 5.5 Reference Manual
Related Documentation Download this Manual
PDF (US Ltr) - 27.2Mb
PDF (A4) - 27.2Mb
PDF (RPM) - 26.2Mb
HTML Download (TGZ) - 6.6Mb
HTML Download (Zip) - 6.6Mb
HTML Download (RPM) - 5.6Mb
Man Pages (TGZ) - 170.5Kb
Man Pages (Zip) - 278.9Kb
Info (Gzip) - 2.6Mb
Info (Zip) - 2.6Mb
Excerpts from this Manual

14.7.10 Redo Log

The redo log is a disk-based data structure used during crash recovery to correct data written by incomplete transactions. During normal operations, the redo log encodes requests to change InnoDB table data that result from SQL statements or low-level API calls. Modifications that did not finish updating the data files before an unexpected shutdown are replayed automatically during initialization, and before the connections are accepted. For information about the role of the redo log in crash recovery, see Section 14.21.2, “InnoDB Recovery”.

By default, the redo log is physically represented on disk as a set of files, named ib_logfile0 and ib_logfile1. MySQL writes to the redo log files in a circular fashion. Data in the redo log is encoded in terms of records affected; this data is collectively referred to as redo. The passage of data through the redo log is represented by an ever-increasing LSN value.

For related information, see:


User Comments
Sign Up Login You must be logged in to post a comment.