Messages in this thread | | | Date | Fri, 2 Aug 2002 15:14:21 -0700 (PDT) | From | "Randy.Dunlap" <> | Subject | Re: BIG files & file systems |
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On Fri, 2 Aug 2002, Albert D. Cahalan wrote:
| Matti Aarnio writes: | | > It depends on many things: | > - Block layer (unsigned long) | > - Page indexes (unsigned long) | > - Filesystem format dependent limits | > - EXT2/EXT3: u32_t FILESYSTEM block index, presuming the EXT2/EXT3 | > is supported only up to 4 kB block sizes, that gives | > you a very hard limit.. of 16 terabytes (16 * "10^12") | | You first hit the triple-indirection limit at 4 TB. | http://www.cs.uml.edu/~acahalan/linux/ext2.gif | | > - ReiserFS: u32_t block indexes presently, u64_t in future; | > block size ranges ? Max size is limited by the | > maximum supported file size, likely 2^63, which is | > roughly 8 * "10^18", or circa 500 000 times larger | > than EXT2/EXT3 format maximum. | | The top 4 st_size bits get stolen, so it's 60-bit sizes. | You also get the 32-bit block limit at 16 TB. | -
For a LinuxWorld presentation in August, I have asked each of the 4 journaling filesystems (ext3, reiserfs, JFS, and XFS) what their filesystem/filesize limits are. Here's what they have told me.
ext3fs reiserfs JFS XFS max filesize: 16 TB# 1 EB 4 PB$ 8 TB% max filesystem size: 2 TB 17.6 TB* 4 PB$ 2 TB!
Notes: #: think sparse files *: 4 KB blocks $: 16 TB on 32-bit architectures %: 4 KB pages !: block device limit
-- ~Randy
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