<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
</head>
<body text="#000000" bgcolor="#FFFFFF">
<div class="moz-cite-prefix">On 10/12/18 5:46 PM, Sherpa Sherpa
wrote:<br>
</div>
<blockquote type="cite"
cite="mid:CACkv3pVvLc5L0QgB0j-vog+O_Lt7+GJLH3ZGzyuk1AK2pvmX=g@mail.gmail.com">
<meta http-equiv="content-type" content="text/html; charset=UTF-8">
<div dir="ltr">Thank you for reply i dont mind if fstab sees
partitions. <span class="gmail-im" style="color:rgb(80,0,80)"> I
read this "To avoid striping performance<br>
problems LVM can't tell that two PVs are on the same physical
disk, so if<br>
you create a striped LV then the stripes could be on different
partitions </span> on the same disk resulting in a *decrease*
in performance rather than an<span class="gmail-im"
style="color:rgb(80,0,80)"> increase." in the <a
href="http://tldp.org" moz-do-not-send="true">tldp.org</a>
but does this apply to disks made from RAID backend ?</span></div>
</blockquote>
<p><br>
</p>
<p>If you use partitioning, only create one partition per backing
device and use it as a PV.<br>
This avoids striping across multiple PVs on the same backing
device.</p>
<p>The same config flaw (i.e. use multiple partitions on the same
backing device as PVs thus potentially<br>
stripe across them) may apply to any backing store allowing for
partitioning. So don't do it on SW/HW RAID either.<br>
</p>
<p>Heinz</p>
<p><br>
</p>
<blockquote type="cite"
cite="mid:CACkv3pVvLc5L0QgB0j-vog+O_Lt7+GJLH3ZGzyuk1AK2pvmX=g@mail.gmail.com">
<div dir="ltr">
<div>
<h3 class="gmail-iw"
style="overflow:hidden;white-space:nowrap;max-width:92%;font-size:0.75rem;font-weight:inherit;margin:inherit;font-family:Roboto,RobotoDraft,Helvetica,Arial,sans-serif;letter-spacing:0.3px;color:rgb(95,99,104);line-height:20px"><br>
</h3>
<div>
<div dir="ltr" class="m_-8662274235435088732gmail_signature"
data-smartmail="gmail_signature">
<div dir="ltr">
<div>Warm Regards<br>
</div>
Urgen Sherpa<br>
</div>
</div>
</div>
<br>
</div>
</div>
<br>
<div class="gmail_quote">
<div dir="ltr">On Fri, Oct 12, 2018 at 9:09 PM Heinz Mauelshagen
<<a href="mailto:heinzm@redhat.com" target="_blank"
moz-do-not-send="true">heinzm@redhat.com</a>> wrote:<br>
</div>
<blockquote class="gmail_quote" style="margin:0 0 0
.8ex;border-left:1px #ccc solid;padding-left:1ex">
<div text="#000000" bgcolor="#FFFFFF">
<div
class="m_-8662274235435088732m_-8027134236677368943moz-cite-prefix">On
10/11/18 4:31 PM, Emmanuel Gelati wrote:<br>
</div>
<blockquote type="cite">
<div dir="ltr">If you use sdb only for data, you don't
have need to use partition on the disk.<br>
</div>
</blockquote>
<p>Though that's true, keeping 1 partition per disk for each
LVM PV adds additional<br>
'visibility' by tools like fdisk/[cs]fdisk, parted etc.
showing the partition type to be 'Liinux LVM'.<br>
</p>
<p>Using the whole disk, blkid or lsblk will provide that
information still,<br>
e.g. 'blkid --match-token TYPE=LVM2_member'.</p>
<p>Heinz<br>
</p>
<blockquote type="cite"><br>
<div class="gmail_quote">
<div dir="ltr">Il giorno gio 11 ott 2018 alle ore 16:26
David Teigland <<a
href="mailto:teigland@redhat.com" target="_blank"
moz-do-not-send="true">teigland@redhat.com</a>>
ha scritto:<br>
</div>
<blockquote class="gmail_quote" style="margin:0 0 0
.8ex;border-left:1px #ccc solid;padding-left:1ex">On
Thu, Oct 11, 2018 at 08:53:07AM +0545, Sherpa Sherpa
wrote:<br>
> I have LVM(backed by hardware RAID5) with logical
volume and a volume group<br>
> named "dbstore-lv" and "dbstore-vg" which have
sdb1 sdb2 sdb3 created from<br>
> same sdb disk.<br>
<br>
> sdb 8:16 0
19.7T 0 disk<br>
> ├─sdb1 8:17 0
7.7T 0 part<br>
> │ └─dbstore-lv (dm-1) 252:1 0
9.4T 0 lvm /var/db/st01<br>
> ├─sdb2 8:18 0
1.7T 0 part<br>
> │ └─dbstore-lv (dm-1) 252:1 0
9.4T 0 lvm /var/db/st01<br>
> └─sdb3 8:19 0
10.3T 0 part<br>
> └─archive--archivedbstore--lv (dm-0) 252:0
0 10.3T 0 lvm<br>
<br>
> I am assuming this is due to disk seek problem as
the same disk partitions<br>
> are used for same LVM or may be its due to
saturation of the disks<br>
<br>
You shouldn't add different partitions as different
PVs. If it's too late<br>
to fix, it might help to create new LV that uses only
one of the<br>
partitions, e.g. lvcreate -n lv -L size vg /dev/sdb2,
and then copy your<br>
current LV to the new one.<br>
<br>
_______________________________________________<br>
linux-lvm mailing list<br>
<a href="mailto:linux-lvm@redhat.com" target="_blank"
moz-do-not-send="true">linux-lvm@redhat.com</a><br>
<a
href="https://www.redhat.com/mailman/listinfo/linux-lvm"
rel="noreferrer" target="_blank"
moz-do-not-send="true">https://www.redhat.com/mailman/listinfo/linux-lvm</a><br>
read the LVM HOW-TO at <a
href="http://tldp.org/HOWTO/LVM-HOWTO/"
rel="noreferrer" target="_blank"
moz-do-not-send="true">http://tldp.org/HOWTO/LVM-HOWTO/</a></blockquote>
</div>
<br clear="all">
<br>
-- <br>
<div dir="ltr"
class="m_-8662274235435088732m_-8027134236677368943gmail_signature"
data-smartmail="gmail_signature"> .~.<br>
/V\<br>
// \\<br>
/( )\<br>
^`~'^</div>
<br>
<fieldset
class="m_-8662274235435088732m_-8027134236677368943mimeAttachmentHeader"></fieldset>
<pre class="m_-8662274235435088732m_-8027134236677368943moz-quote-pre">_______________________________________________
linux-lvm mailing list
<a class="m_-8662274235435088732m_-8027134236677368943moz-txt-link-abbreviated" href="mailto:linux-lvm@redhat.com" target="_blank" moz-do-not-send="true">linux-lvm@redhat.com</a>
<a class="m_-8662274235435088732m_-8027134236677368943moz-txt-link-freetext" href="https://www.redhat.com/mailman/listinfo/linux-lvm" target="_blank" moz-do-not-send="true">https://www.redhat.com/mailman/listinfo/linux-lvm</a>
read the LVM HOW-TO at <a class="m_-8662274235435088732m_-8027134236677368943moz-txt-link-freetext" href="http://tldp.org/HOWTO/LVM-HOWTO/" target="_blank" moz-do-not-send="true">http://tldp.org/HOWTO/LVM-HOWTO/</a></pre>
</blockquote>
</div>
_______________________________________________<br>
linux-lvm mailing list<br>
<a href="mailto:linux-lvm@redhat.com" target="_blank"
moz-do-not-send="true">linux-lvm@redhat.com</a><br>
<a href="https://www.redhat.com/mailman/listinfo/linux-lvm"
rel="noreferrer" target="_blank" moz-do-not-send="true">https://www.redhat.com/mailman/listinfo/linux-lvm</a><br>
read the LVM HOW-TO at <a
href="http://tldp.org/HOWTO/LVM-HOWTO/" rel="noreferrer"
target="_blank" moz-do-not-send="true">http://tldp.org/HOWTO/LVM-HOWTO/</a></blockquote>
</div>
</blockquote>
<pre class="moz-signature" cols="72">
</pre>
</body>
</html>