[mythtv] Advanced Partition Formatting

Wed Feb 25 14:39:46 EST 2004

On Tue, Feb 24, 2004 at 07:19:45PM -0600, William Powers wrote:

> I took a stab a collecting the available information on filesystem 
> performance for the "Advanced Partition Formatting" section of the 
> HOWTO.  Please feel free to use any part that you feel is useful and 
> discard the rest.
>
> <body style="" vlink="purple" link="blue" lang="EN-US">
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What on Earth is this?

>  ??????b="">There
> is however, one aspect of filesystem performance that can have a
> bearing on the
> performance of MythTV.<span style="">&nbsp; </span>In Linux,
> deleting a file will pretty much tie up the CPU until the deletion has
> been
> completed.

I do not think it is accurate to say that deleting a file ties up the CPU.
In my experience the bottleneck is the amount of I/O generated.

>  # mkfs.ext3 -T largefile4 -m 0 /dev/hdb1

> "-T largefile4" option creates one inode per 4 megabytes, which can
> provide a few percent more storage space.<span style="">&nbsp;
> </span>However, tests indicate that using the "-T largefile4" option
> can drastically increase the amount of time required to delete a large
> file and
> thus it should only be used with encoder settings that produce small
> video
> files (YMMV).

Is this true?  I don't see how the total number of inodes would affect
deletion time at all.

-- 
 - mdz