Gentoo Archives: gentoo-user

From: James Cloos <cloos@×××××××.com>
To: Alan Mackenzie <acm@×××.de>
Cc: gentoo-user@l.g.o
Subject: Re: [gentoo-user] Ext3 FS File Size Limits
Date: Mon, 03 Jun 2013 01:15:00
Message-Id: m3wqqc2e3s.fsf@carbon.jhcloos.org
In Reply to: Re: [gentoo-user] Ext3 FS File Size Limits by Alan Mackenzie
1 >>>>> "AM" == Alan Mackenzie <acm@×××.de> writes:
2
3 AM> Haven't a clue. I would have expected the maximum file size to be a
4 AM> number of blocks, which makes it seem strange that doubling the block
5 AM> size multiplies max file size by 16.
6
7 Doubling the block size means that the structure specifying which blocks
8 are in use by a given inode is twice as long. And the structure
9 supports indirect blocks, which contain references to the actual blocks
10 used by the file data. So you get one doubling for the size of the
11 blocks, and another three for the number of blocks each file can use.
12
13 Most ext3 and ext4 filesystems use 4096 octet blocks.
14
15 -JimC
16 --
17 James Cloos <cloos@×××××××.com> OpenPGP: 1024D/ED7DAEA6