[linux-lvm] Re: [linux-lvm] Verständnis von Stripes bei LVM

[Goetz Bock <bock@blacknet.de>]

[-- Attachment #1: Type: text/plain, Size: 1549 bytes --]


On Fri, Sep 14 '01 at 11:32, Pawlowski Julian wrote:
> ich habe eine Frage zur Funktion von Stripes beim LVM. Wofür genau
> benötigt man diese Funktion? Wird damit das LV auf mehrere der reellen
> Partitionen zwecks Performancegewinn verteilt?
Yes, that's exactly the intended bahaviour. if you have n (e.g. 2 or
more) PV than a striped LV is splitted between this n PV. This can
increase performance (like RIAD0 does) but it may backfire, if your PV
are on the same reald device.
If you want to use striped LVs, only use one PV per real device.

e.g.: 4 HDDs of 40GB each (sda, sdb, sdc, sdd)

you boot from sda and decide to have a 512MB root/boot partition for
this. Than make 3 swap partitiones on sdb, sdc and sdd.

on each device make a seccond partition with the rest of the space.
create a PV out of each of this 4 partitions.

you now have:

sda: sda1    512MB  root/boot
     sda2   39.5GB  PV1
sdb: sdb1    512MB  swap
     sdb2   39.5GB  PV2
sdc: sdc1    512MB  swap
     sdc2   39.5GB  PV3
sdd: sdd1    512MB  swap
     sdd2   39.5GB  PV4

VG1:       118.0GB  PV1 PV2 PV3 PV4

if you now make a striped LV of 20GB it will use 5GB on each PV and the
stripes will be read from PV1 PV2 PV3 PV4 PV1 PV2 PV3 PV4 ...

BTW: if you write your question in english a lot more people will be
     able to send you a reply.

PS: und wenn Du willst kann ich Dir das ganze gerne nochmal auf Deutsch
    schicken.

-- 
Goetz Bock                                              IT Consultant
Dipl.-Inf. Univ.

[-- Attachment #2: Type: application/pgp-signature, Size: 232 bytes --]