Oracle Defragging?

[jkornhiser]

I'm seeing conflicting evidence about whether or not an Oracle data file can actually be defragmented so I thought this might be a good place to get some 'authoritative' feedback.

 

I've been running Defraggler repeatedly on a 120 GB (Windows) disk that is about 52% in use, and contains two Oracle data files. It always seems to hang on one of the data files after doing its thing for a few hours and in terms of progress, has turned a 97% fragmented drive into about 58% fragmented after several passes. I decided to run it in debug mode yesterday and when I checked on it today, Defraggler had apparently closed itself down. I checked the end of the log file and the following message has been repeated over and over:

 

[2014-11-03] [16:09:11.894] 00c48 1 DefragVolumeSinglePassHelper::LayFileAt#380 MoveFileRegionWithMarking for file "D:\oracle\ORADATA\OPENTMS\OPENROADS_DATA.ORA" to 9644945, 906924, 2 finished (hr=0x00000000). Destination block is not free.

 

I was thinking perhaps there is not enough contiguous free space to handle the resulting 32 GB data file so I'm defragging free space now but I wanted to see if there are any thoughts about whether its even possible to defrag an Oracle file.

 

~John K.

Defraggler2_18_9452014-11-03_11-14.zip