Linux LVM users
 help / color / mirror / Atom feed
From: "Heinz J . Mauelshagen" <mauelshagen@sistina.com>
To: linux-lvm@sistina.com
Subject: Re: [linux-lvm] Allocation policies
Date: Wed Sep 11 05:53:04 2002	[thread overview]
Message-ID: <20020911122807.C26854@sistina.com> (raw)
In-Reply-To: <3D7E4135.9EE88518@storix.com>; from anthony@storix.com on Tue, Sep 10, 2002 at 12:00:05PM -0700

On Tue, Sep 10, 2002 at 12:00:05PM -0700, Anthony Johnson wrote:
> I know there are 2 allocation policies, contiguous and next free. Is
> there any information that describes in detail how LVM determines the
> extents to assign to a logical volume with it is created or extended?

It goes by the sequence defined by the internal PV number shown by
"vgdisplay -v". Free space on PVs with lower internal is allocated first.

> For example, if the policy is "contiguous", must the LV contain all
> contiguous extents

Yes.

> or does it use a "best-case" scenario,

No.

> and how would
> that work? Likewise, in the "next free" scenario, is there any weight
> given to contiguous space, does it automatically allocate across PVs,
> etc?

No, there's no weight.
In both cases it does allocate accross PVs.
In the contiguous case, it can't allocate on the same PV unless there's free
space after the already allocated extents.
You need to use pvmove if there's not free space following to move extents
allocated to other LVs away.

> 
> Thanks!
> Anthony
> 
> _______________________________________________
> linux-lvm mailing list
> linux-lvm@sistina.com
> http://lists.sistina.com/mailman/listinfo/linux-lvm
> read the LVM HOW-TO at http://www.sistina.com/lvm/Pages/howto.html

-- 

Regards,
Heinz    -- The LVM Guy --

*** Software bugs are stupid.
    Nevertheless it needs not so stupid people to solve them ***

=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-

Heinz Mauelshagen                                 Sistina Software Inc.
Senior Consultant/Developer                       Am Sonnenhang 11
                                                  56242 Marienrachdorf
                                                  Germany
Mauelshagen@Sistina.com                           +49 2626 141200
                                                       FAX 924446
=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-

      reply	other threads:[~2002-09-11  5:53 UTC|newest]

Thread overview: 2+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2002-09-10 14:08 [linux-lvm] Allocation policies Anthony Johnson
2002-09-11  5:53 ` Heinz J . Mauelshagen [this message]

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20020911122807.C26854@sistina.com \
    --to=mauelshagen@sistina.com \
    --cc=linux-lvm@sistina.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body. 
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox