tune2fs -m

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Tux
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tune2fs -m

Post by Tux »

Hey good people,

What would you all recommend as the lowest reserved block percentage on an ext3 partition used purely for data?
I was thinking perhaps 3%
Wise, or nay?

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Void Main
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Post by Void Main »

Heck, go for 1%. If you have 100GB drive that's still 1GB reserved for root. On a data drive it's not that big of a deal.

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Post by Tux »

The thing is i've heard it was also to avoid fragmentation.
http://lists.debian.org/debian-user/1999/10/msg01917.html wrote:Yes, but the actual _reason_ for that is that the block allocation
algorithms of the ext2 filesystems need at least 5% of free space
to work properly. Ever wondered why you do not need to defragment an
ext2 filesystem?

You can tune the free space and set it to 1% or so, but if you write
to the partition a lot and it fills up, it will get a) very slow
to write to and b) fragmented, so very slow to read from as well.

For a filesystem with static content (like /usr) that you fill up
only once and then just read from it doesn't matter as much.
https://listman.redhat.com/archives/ext3-users/2002-February/msg00026.html wrote:Ummm, the 5% reservation is to prevent the high levels of
fragmentation that occur when the filesystem is near full (something
that I wish Windows would adopt as standard too ;-).
I don't know enough about ext3 to tell if this is codswallop. It sounds reasonable...

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Post by Void Main »

Ok I take it back, go with the 5%. :) I've also read this now that you mention it and sounds reasonable. Personally, I've always gone with defaults. I find when I start thinking I know more than the author of the tools it eventually comes back to bite me.

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Post by Tux »

Ok, cheers. I'll go with 5%.


Also on the topic of fragmentation, do you know of any decent defrag tools for fat32 volumes from Linux?
See I have an MP3 player with a FAT32 disk and I think it needs defragmenting and I don't want to use Windows.

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Post by Void Main »

No I don't. I know you can fsck them (man fsck.vfat) but I don't know of a way to defrag them.

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