Re: [vox-tech] resizing harddrive
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Re: [vox-tech] resizing harddrive
Since some people say Gigabytes are 10^9 and others 2^30. To be consistent
with units, I'll use bytes, MiB (2^20 == 1048576) and GiB (2^30 = 1073741824).
On Thu, Feb 27, 2003 at 10:26:40PM -0800, Ryan wrote:
> okay so after backing everything up for 4 hours I did what you said:
> The partition is indeed bigger, but not was large as I had expected.
> It says I only have about 36GB free. Here is a df
You had unrealistic expectations...
You should have about 5.5 GiB more of available space than before.
That is hard to be certain about, because you didn't include the before
df in your email.
Let's break a few things down... here are the relevant log lines.
Real Disk Size: 40020664320 B 38166 MiB 37.3 GiB
Lost to Filesystem Overhead: 320880640 B 306 MiB 0.3 GiB
Available Filesystem: 39699783680 B 37860 MiB 37.0 GiB
Lost to Reserved Blocks: 2000797696 B 1908 MiB 1.9 GiB
Lost to Journal Overhead: 33615872 B 32 MiB 0.0 GiB
Available to Users: 37665370112 B 35920 MiB 35.1 GiB
# hdb: 78165360 sectors (40021 MB) w/2048KiB Cache, CHS=4865/255/63, (U)DMA
# CurCHS=16383/16/63, CurSects=-66060037, LBA=yes, LBAsects=78165360
You're drive has 78165360 sectors (512 bytes each) or
40020664320 bytes of space... which is 38166 MiB or 37.3 GiB.
> Filesystem 1k-blocks Used Available Use% Mounted on
> /dev/hdb1 38769320 32828 36782588 1% /home/media
The filesystem contains 38769320 usable blocks (1k bytes each) or
39699783680 bytes (37860 MiB) or (37 GiB) of space.
Which means you lost about 0.8% or 40020664320-39699783680 = 320880640
320880640 bytes (306 MiB) do to hidden filesystem overhead...
"Used = 32828 blocks" means another
33615872 bytes (32 MiB) are taken by the filesystem journal.
You may notice that '1k-blocks' is 38769320, and 'Used' + 'Available'
is 36815416. That is 2000797696 bytes or so... those 5% of blocks, are
reserved to help prevent fragmentation, speed up writing, and other
useful magic filesystem purposes. (Reserved space is standard on
any Unix filesystem I've ever used, some even reserve 10%).
2000797696 bytes (1908 MiB) or (1.9 GiB)
I recommend not doing this...
But if you want to totally want to destroy performance once you
start using most of the 5% cushion of "reserved blocks"... you can
set the number of reserved blocks to 0 with the following command:
tune2fs -r 0 /dev/hdb1
I recommend unmounting the filesystem first.
# /dev/hdb1 1 4111 33021576 83 Linux
I can't exactly compare apples to apples, since I don't have a df from
before. But the new partition is 6206570496 bytes or 5919 MiB or 5.8
GiB... larger, which should have gone almost straight to the available
blocks (minus the 5% reserved).
The only possible correction was the -i 16384, you might have been better
with -i 32768... which would have cut into the 'Overhead' number above,
by creating fewer inodes, which would reduce the number of files you can
store. If you haven't already reloaded the data onto the drive... you
can check out "df -i" to see how many inodes are available... that tells
you how many files you can have. If the number is "too big" for what
you KNOW you need... run:
mke2fs -j -b 4096 -i 32768 /dev/hdb1
... but we are talking about getting some of 306 MiB.
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