1419921 - moonshot lvm volume groups should not span past the nvme0 device

Status: RESOLVED WONTFIX

(Infrastructure & Operations :: RelOps: General, task)

Description

[Jake Watkins [:dividehex]]

It looks like all the zen server local SR groups are comprised of a LVM vg that include an nvme pv device AND partition pv on the boot sda device.  This could cause a file IO performance hit if a VMs lg ends up spilling over to the sda pv.

We should remove the sda as a pv from lg on the existing moonhost xen servers AND make sure this doesn't happen again once we establish the pxe boot installation of xen.

[root@xenserver264 ~]# vgdisplay
  --- Volume group ---
  VG Name               VG_XenStorage-995fc433-af76-5f5b-5d83-3ee81355fbd1
  System ID
  Format                lvm2
  Metadata Areas        2
  Metadata Sequence No  14
  VG Access             read/write
  VG Status             resizable
  MAX LV                0
  Cur LV                10
  Open LV               1
  Max PV                0
  Cur PV                2
  Act PV                2
  VG Size               256.57 GiB
  PE Size               4.00 MiB
  Total PE              65683
  Alloc PE / Size       46215 / 180.53 GiB
  Free  PE / Size       19468 / 76.05 GiB
  VG UUID               sxqBYE-gXUl-lige-AbhA-9XW4-eyEn-pvTbV3

[root@xenserver264 ~]# pvdisplay
  --- Physical volume ---
  PV Name               /dev/nvme0n1
  VG Name               VG_XenStorage-995fc433-af76-5f5b-5d83-3ee81355fbd1
  PV Size               238.47 GiB / not usable 14.34 MiB
  Allocatable           yes
  PE Size               4.00 MiB
  Total PE              61046
  Free PE               14831
  Allocated PE          46215
  PV UUID               CqfpB7-LKKi-cZxA-ZMB0-CKAL-23GJ-iZU0Vl

  --- Physical volume ---
  PV Name               /dev/sda3
  VG Name               VG_XenStorage-995fc433-af76-5f5b-5d83-3ee81355fbd1
  PV Size               18.13 GiB / not usable 12.32 MiB
  Allocatable           yes
  PE Size               4.00 MiB
  Total PE              4637
  Free PE               4637
  Allocated PE          0
  PV UUID               fM8rxU-hKka-NRKh-YY4T-Vjyn-anoi-7GgjK1

Comment 1

[Jake Watkins [:dividehex]]

If we revisit Xen, this can be reopend.  As it is, most of the moonshot nodes have had their gpt/lvm metadata wiped prior to baremetal install.  If we do revisit and start installing Xen, we should make sure not to span the vg across the pvs (sda and nvme)