[ parted-Bugs-302454 ] RFE: documentation of upper size limits for filesystems & partitions

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Bugs item #302454, was opened at 2005-11-03 11:36
You can respond by visiting: 
http://alioth.debian.org/tracker/?func=detail&atid=410685&aid=302454&group_id=30287

Category: None
Group: None
Status: Open
Resolution: None
>Priority: 4
Submitted By: Vince McIntyre (xipmix-guest)
>Assigned to: Leslie P. Polzer (dejari-guest)
Summary: RFE: documentation of upper size limits for filesystems & partitions

Initial Comment:
Hi

(before submitting this I did several searches through
 parted-1.6.24/doc/parted.info. I couldn't find much.)

Given the number of filesystems and partition types that parted supports
this improvement will take a while to do. But now that 1 Tbyte disks are
getting common and multi-Tb raid systems are no longer rare, I think it is
necessary to at least document the following:

 * the 2Tbyte size limitations in msdos disklabels,
 * why GPT disklabels are useful (what is their upper limit)
 * ext2 filesystem limitations at 2Tbyte
   (actually 2^31 blocks, allowed blocksizes are 1k,4k,8k)
 * upper size limits of FAT32
 * the limits are not just due to parted, the OS kernel and in some cases
   the hardware disk controller has a role to play too (CHS, LBA addressing 
   schemes)
 * and then there are the bootable partition size limits...

The main focus here should be what parted's known limits are, ie if
you have the right h/w to get this big, parted will work correctly.

It would be useful to write some tests to check for regresssions in
parted at the 2Tbyte boundary. That's a lot of data to lose...
Just publishing the results of tests you conduct, with an explicit
"no guarantee" statement about other people's hardware, would be useful.

A second question:
  does parted use mke2fs from e2fsprogs or its own code?

e2fsprogs currently does not really support filesystems > 2Tbyte.
(http://e2fsprogs.sourceforge.net/e2fsprogs-release.html#1.38)

Some reference links - 
http://en.wikipedia.org/wiki/GUID_Partition_Table
http://en.wikipedia.org/wiki/Hard_drives
http://en.wikipedia.org/wiki/Logical_block_addressing
http://www.allensmith.net/Storage/HDDlimit/Address.htm
(this gives a good table showing CHS addressing limitations)



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>Comment By: Leslie P. Polzer (dejari-guest)
Date: 2005-11-12 19:33

Message:
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Parted has own code for ext2 creation, but I don't know whether some was taken 
from e2fsprogs. Will check.

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You can respond by visiting: 
http://alioth.debian.org/tracker/?func=detail&atid=410685&aid=302454&group_id=30287