| Bug #22310 | dead/deceptive code in FileLogHandler::writeFooter() and File_class::flush | ||
|---|---|---|---|
| Submitted: | 13 Sep 2006 13:22 | Modified: | 3 Jan 2007 2:57 |
| Reporter: | Stewart Smith | Email Updates: | |
| Status: | Closed | Impact on me: | |
| Category: | MySQL Cluster: Cluster (NDB) storage engine | Severity: | S3 (Non-critical) |
| Version: | 5.0,5.1 | OS: | |
| Assigned to: | Stewart Smith | CPU Architecture: | Any |
[27 Oct 2006 8:08]
Bugs System
A patch for this bug has been committed. After review, it may be pushed to the relevant source trees for release in the next version. You can access the patch from: http://lists.mysql.com/commits/14458 ChangeSet@1.2275, 2006-10-27 18:08:08+10:00, stewart@willster.(none) +2 -0 BUG#22310 dead/deceptive code in FileLogHandler::writeFooter() and File_class::flush make the File_class::flush() method actually flush the stdio buffers.
[29 Dec 2006 0:35]
Stewart Smith
5.0 smaller patch, just correcting the functionality (slight possibility to cause real-world issue, probably not) pushed to 5.0-ndb tree
[29 Dec 2006 8:19]
Stewart Smith
pushed to 5.0.34
[3 Jan 2007 2:57]
Jon Stephens
Does not appear to impact end-user functionality; closed without further action.
Description: In FileLogHandler::writeFooter(), 00128 // Needed on Cello since writes to the flash disk does not happen until 00129 // we flush and fsync. 00130 m_pLogFile->flush(); 00172 int 00173 File_class::flush() const 00174 { 00175 #if defined NDB_OSE || defined NDB_SOFTOSE 00176 ::fflush(m_file); 00177 return ::fsync(::fileno(m_file)); 00178 #else 00179 return 0; 00180 #endif 00181 } So things are rather deceiving here... There can be two possible intentions for this code: 1) implement periodic flushing of dirty pages to disk on Cello. 2) log messages should be persistent on disk on system failure. 2 isn't possible with a text log file and 1 is old and confusing (especially if another user of File_class were to come along and try to flush() thinking it put things on disk). How to repeat: not repeat - dead code Suggested fix: remove dead code so to avoid confusing coders in the future.