Reserved block count for Large Filesystem

Jure Pečar pegasus at
Fri Jan 23 11:26:10 UTC 2009

On Fri, 23 Jan 2009 06:10:47 -0500
Alex Fler <alexfler at> wrote:

> Hi All,
> On large FS like 100gb default value of "Reserved block count" takes 5%
> of usable disk, can this value be safely changed to 1% and not affect a
> performance ? Is a reservation size of 1gb enough for 100gb disk ? And
> when we have even larger filesystem like 1Tb default "Reserved block
> count" is 50GB, is it an absolutely minimum must have reserved number of
> space for disk performance, or it's just a legacy concept which can be
> adjusted? 

These days I simply mkfs all my large non-root and non-var filesystems with
-m 0, setting reserved block count to 0%.


Jure Pečar

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