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JMDSC
19th November 2004, 11:37 PM
Hello all,

I have read that the EXT3 file system as compared to the EXT2 file system is journaled which I believe is less prone to loss of data.

What does "journaled" actually mean?
What are the other advantages to EXT3 as opposed to EXT2?

Thanks.

Emily
20th November 2004, 05:37 AM
when a filesystem is "journalled" it means there is an actual journal that the kernel keeps of every atomic disk read/write that it does... the reason is that in a normal filesystem, power loss actually can cut off an OS before or in the middle of writing something to the disk, ending up corrupting everything

a journal tends to help the situation so that even if the computer gets loses power or the system crashes, it can recover the journal later to help recover the filesystem

on a related note, using the command "sync" flushes everything out to disk immediately

JMDSC
20th November 2004, 09:18 PM

Thanks Emily

Jman
21st November 2004, 01:29 AM
Journaling is just about the only difference, which is why ext2 can be converted to 3 easily.