[mythtv-users] Block size for ext3 partition

[Michael T. Dean]

On 01/20/2008 03:48 AM, Phill Edwards wrote:
> In order to make it easier to install CentOS I am going to reformat my
> JFS file system which stores my recordings to EXT3. It's a 320GB IDE
> disk. The archives have lots of file system discussions but I can't
> find anything which says what block size to format the EXT3 partition
> with for storing large files like recordings. Can anybody advise?

I use the default, which turned out to be 4096 bytes on my 12.8GiB root 
partition and on my 688GiB partitions of my 750GB drives (i.e. will 
probably be the default on any filesystem on a modern-sized hard 
drive--including on your 320GB hard drive), though my 24MiB boot 
partition only has a 1024 byte block size.  The 4096-byte block size 
allows a maximum file size of 2TiB and a maximum filesystem size of 
16TiB--neither of which presents a problem for me.

Note that I did not specify the '-T largefile' (nor largefile4) argument 
to mke2fs.  I figure that since I can't add new inodes without 
reformatting, it's better to have too many than not enough, but you can 
use them, i.e. on a recordings partition, if you're sure they'll work 
(largefile gives 1 inode per 1MiB of storage and largefile4 gives 
1/4MiB--which shouldn't be a problem, but you can decide for yourself).

I do recommend if using ext{2,3} for the recordings partition that you 
enable slow deletes in mythtv-setup.

Delete files slowly
Some filesystems use a lot of resources when deleting large recording 
files.  This option makes Myth delete the file slowly on this backend to 
lessen the impact.

HTH,
Mike