space available is contiguous or not

[Popy]

I have 8GB space in vg00 and want to create a 6 GB additional swap. How can check if this space is contiguous or not ?

I can't try an lvcreate -L 6000 -c y as I have to wait for the schedule.

Thanks

[Torsten.]

Good question.

Get the disk device file and perform a

pvdisplay -v /dev/dsk/...

and inspect the PEs.

[Popy]

Torsten,

Here is how the PEs are,

The first free PE is 3215 and there are 499 PEs showing free ( 3215 to 3713)

then the next free PE starts 4040 and it goes to 4303


Does this mean I can create a contiguous LV using 499 PEs ( PEs 3215 to 3713) ? My PE size is 16 MB, if I issue lvcreate command will it take this set of PEs ? I don't have any free PEs below 3215.

Appreciate your help.

RV

[Venkatesh BL]

Although I haven't used myself, I see "-C contiguous" in the 'lvcreate' manpage. May be that would cater to your need.

[Popy]

test

[Torsten.]

I think you have enough space to create your 6GB LVOL now.

[Mridul Shrivastava]

16*499=7984MB Hence we have contiguous PEs which can be assigned, hence creating a contiguous volume should not be an issue here.

Try creating lvol with -C y, this will take care of the following:

+ Physical extents are allocated in ascending order,

To limit the allocation to specific physical volumes, specify the physical volume names as pv_path arguments. Otherwise, all of the physical volumes in a volume group are available for allocating new physical extents. LVM always ensures that physical extent allocation can satisfy the current allocation policy or policies. If a physical volume is not suitable for use with a certain allocation policy, it is
not used during physical extent allocation, even it is specified in a pv_path argument.

[Popy]

Thanks Torsten & Mridul. I'll try this next week.

Pops