Re: Re: which to use: ext3, JFS, XFS, ReiserFS? [Was: new userquestion: debian on a Thinkpad T61]
On Jan 19, 2008 5:35 AM, Jan Willem Stumpel <firstname.lastname@example.org> wrote:
> I am especially put off by the Wikipedia article on ext3. It gives
> a rather long list of "disadvantages". One of them ("No
> checksumming in journal") even sounds pretty frightening. The list
> of "advantages" is very short, and they are mostly advantages over
> Reiserfs and other non-ext2 systems, not advantages over ext2.
ext2 and 3 are 100% identical save for the journal. ext2 is just as
unsafe as ext3, with ext2 perhaps being less safe due to the total
lack of journaling. That being said, I used to suffer unclean
shutdowns all the time in the 90's (family members frobbing power
switches wrecklessly) that ext2 would frequently lose data on,
switching to ext3 stopped the data loss and extreme fsck times.
> 1. Is it true that ext3 always lets you recover smoothly after a
> "freeze and pull the plug", or after a power cut? Or are there
> still "ifs" and "buts"?
There are still if's and but's, but they're small and I've yet to
experience them in the better part of a decade's use of ext3.
> 2. Is significant room on the disk (or partition) taken by the
> journal? By how much can I expect the disk capacity to be
I personally don't remember the exact amount, but it is more or less
statistically insignificant with modern drive sizes.
> 3. It is said ext3 is "slow". Does this apply to writing only, or
> also to reading?
Not sure how it's slow against perhaps the buggy and now unlikely to
receive future development ReiserFS...
> I.e., is there a danger that when I play a
> film with mplayer, I'll get the dreaded message "Your system is
> TOO SLOW to play this"?
No, that's a CPU features thing, IIRC.
> 4. I have my whole Linux system, apart from swap (i.e. the root,
> and everything that branches off it, like /boot, /var, /usr)
> just on one logical partition. Can I still convert to ext3,
> possibly by using a Knoppix or Ubuntu CD-ROM to boot from?
You can, but it's generally easier to do it on the fly... tune2fs -j
<device>; this can be done to mounted filesystems without consequence.
> 5. Where can I find reliable, step-by-step instructions for the
> conversion? There are several such instruction sites on the
> Web, but I am not sure they always agree.
Step 1: Get root privileges.
Step 2: Type tune2fs -j /dev/whatever
Step 3: Remount the filesystem ext3...