[linux-lvm] Beginner Questions

[Joseph L. Casale]

Thank you for the response. The first is insignificant, but there is ½ a terabyte missing on the second which is listed as 8192 EB? It should be ~500 GB free?

Thanks!
jlc

From: linux-lvm-bounces at redhat.com [mailto:linux-lvm-bounces at redhat.com] On Behalf Of pham_cuong at emc.com
Sent: Monday, November 12, 2007 2:56 PM
To: linux-lvm at redhat.com
Subject: RE: [linux-lvm] Beginner Questions

When you format, unless you specify the block size, the default block size is used.
The default block size is defined based on the size of the logical disk (partition) size that you've created.
Any disk space left over from the format is listed as unusable (for the block size that's being used) can not be used because it's not a multiple of the block size used to format that logical drive/partition.

The only way that you can make use of the remaining very small disk space is to use the smaller block size when formatting.   However, unless you know exactly what you're doing, it's not advisable for you to do so since this will more likely impact the performance of your logical drive/partition.  A lot of testing were done to determine the optimal block size based on the size of the logical drive/partition that you've created.

Except for academic reason(s), you should not be concerned with such a small left over.

Regards,


________________________________
From: linux-lvm-bounces at redhat.com [mailto:linux-lvm-bounces at redhat.com] On Behalf Of Joseph L. Casale
Sent: Monday, November 12, 2007 4:34 PM
To: 'linux-lvm at redhat.com'
Subject: [linux-lvm] Beginner Questions
Hi,
I have Fedora Core 7 with  LVM version: 2.02.24 (2007-03-19), Library version: 1.02.17 (2007-01-29) and  Driver version: 4.11.0 setup.

I have two hardware raid cards each with one array partitioned fully at 799.9GB and 1499.9GB. When I try run to pvcreate /dev/sdb1 /dev/sdc1 it creates the pvs and when I run pvdisplay I get this:

  --- Physical volume ---
  PV Name               /dev/sdb1
  VG Name               name
  PV Size               745.00 GB / not usable 3.67 MB
  Allocatable           yes
  PE Size (KByte)       4096
  Total PE              190718
  Free PE               190718
  Allocated PE          0
  PV UUID               yQyVCe-tiS4-Ma1E-hilJ-niuG-KXL9-jkKVIk

  --- Physical volume ---
  PV Name               /dev/sdc1
  VG Name               name
  PV Size               1024.00 GB / not usable 8192.00 EB
  Allocatable           yes
  PE Size (KByte)       4096
  Total PE              357626
  Free PE               357626
  Allocated PE          0
  PV UUID               PURHhY-Lo1T-5bif-HjGP-dP3o-NVTs-71ZKUm

Why is some space "not usable"?

Thanks!
jlc
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://listman.redhat.com/archives/linux-lvm/attachments/20071112/3b346396/attachment.htm>