|
Home > Archive > Data Storage > July 2004 > EMC Dart FS overhead
You are viewing an archived Text-only version of the thread.
To view this thread in it's original format and/or if you want to reply to
this thread please [click here]
| Author |
EMC Dart FS overhead
|
|
| Replicant 2004-07-20, 5:45 pm |
| When a Dart Filesystem is built, does it automatically allocate 10% of
space for overhead? We have been looking at our various filesystems
provided over a Celerra and see a discrepancy between what we have
recorded is there in files and what the df says is there. We know the
raw is around 6.1 Tb and we seem to be missing almost exactly 10% of
that....
more curious that anything.
thanks,
Apoc
email: apocalypsetroll@usa.net
I dont get out here much so if someone could cross to my email it
would be appreciated.
| |
|
| On 20 Jul 2004 13:36:56 -0700, apocalypsetroll@usa.net (Replicant)
wrote:
>When a Dart Filesystem is built, does it automatically allocate 10% of
>space for overhead? We have been looking at our various filesystems
>provided over a Celerra and see a discrepancy between what we have
>recorded is there in files and what the df says is there. We know the
>raw is around 6.1 Tb and we seem to be missing almost exactly 10% of
>that....
The Celerra doesn't use the same metavol for checkpoint overheads (if
that's what you were thinking of) as the primary file system. You
have to specify a metavol (the savvol) for this purpose, so that won't
be where you're losing the 10%.
Celerra uses 7 hypervols for its normal operational overheads, such as
logging, data mover boot volumes, gatekeepers, etc. So again, this
won't be the problem either.
Are you sure this apparent loss of capacity isn't just down to the
Celerra block size? It's usually 8 KB, this can sometimes lead to
apparently 'lost' space. That's my best guess at where your capacity
has gone.
If you really want to know, ask your EMC rep to contact NSG
Engineering for you.
HTH.
HVB.
|
|
|
|
|