Re: Does 32.1% non-contiguous mean severely fragmented?

[Tetsuo Handa]

Hello.

Theodore Tso wrote:
 beginning of every single block group.  You have a small number of
 files on your system (349) occupying an average of 348 megabytes.  So
 it's not at all surprising that the contiguous percentage is 32%.
I see, thank you. Yes, there are many files splitted in 2GB each.

But what is surprising for me is that I have to wait for more than
five minutes to save/restore the virtual machine's 512MB-RAM image
(usually it takes less than five seconds).
Hdparm reports DMA is on and e2fsck reports no errors,
so I thought it is severely fragmented.
May be I should backup all virtual machine's data and
format the partition and restore them.

-
To unsubscribe from this list: send the line unsubscribe linux-fsdevel in
the body of a message to [EMAIL PROTECTED]
More majordomo info at  http://vger.kernel.org/majordomo-info.html

Re: Does \32.1% non-contigunous\ mean severely fragmented?

[Theodore Tso]

On Fri, Oct 19, 2007 at 10:49:03AM +0900, Tetsuo Handa wrote:

 /data/VMware: 349/19546112 files (32.1% non-contiguous), 31019203/39072080 
 blocks
 
 Does non-contiguous mean fragmented?
 If so, where is ext3defrag?

Not necessarily; it just means that 32% of your files have at least
one discontinuity.  Given the ext3 layout, by definition every 128
megs there will be a discontinuity because of the metadata at the
beginning of every single block group.  You have a small number of
files on your system (349) occupying an average of 348 megabytes.  So
it's not at all surprising that the contiguous percentage is 32%.

The recent Flex BG feature that was recently pulled into 2.6.23-git14
for ext4 is desgined to avoid this issue, but a seek every 128 megs is
for most workloads not a big deal and will hopefully not cause you any
problems.

- Ted
-
To unsubscribe from this list: send the line unsubscribe linux-fsdevel in
the body of a message to [EMAIL PROTECTED]
More majordomo info at  http://vger.kernel.org/majordomo-info.html