LVM: how to avoid scanning all devices
When calling LVM commands it seems they all scan all disks for physical volumes. This is annoying because it spins up all disks that are currently idle and causes long delays to wait for these disks to come up. Also, I don't understand why LVM commands scan the disks so often since the information is in /etc/lvm already. For example a command like vgdisplay vg0 where vg0 is actively used and on a disk that is up and running still causes a long delay because it scans all my devices for other volumes although this is completely unneeded. IMO only an explicit call to vgscan should scan for and update all LVM information. Steve
Re: LVM: how to avoid scanning all devices
Hi Steve, On Fri, Dec 15, 2017 at 01:19:46PM +0100, Steve Keller wrote: > When calling LVM commands it seems they all scan all disks for > physical volumes. This is annoying because it spins up all disks that > are currently idle and causes long delays to wait for these disks to > come up. Can you avoid it by using global_filter to restrict LVM's operation to certain devices? Cheers, Andy -- https://bitfolk.com/ -- No-nonsense VPS hosting
Re: LVM: how to avoid scanning all devices
On 15 Dec 2017 11:36 pm, "Steve Keller" wrote: When calling LVM commands it seems they all scan all disks for physical volumes. This is annoying because it spins up all disks that are currently idle and causes long delays to wait for these disks to come up. Also, I don't understand why LVM commands scan the disks so often since the information is in /etc/lvm already. For example a command like vgdisplay vg0 where vg0 is actively used and on a disk that is up and running still causes a long delay because it scans all my devices for other volumes although this is completely unneeded. IMO only an explicit call to vgscan should scan for and update all LVM information. Steve Look at filter examples in /etc/lvm/lvm.conf
Re: LVM: how to avoid scanning all devices
On Wed, Dec 20, 2017 at 02:17:59PM +1100, Igor Cicimov wrote: > Look at filter examples in /etc/lvm/lvm.conf That's not what I'm looking for. I *do* have LVM physical and logical volumes on most of my drives, e.g. a volume group on my backup drive. And I want an explicit call to vgscan to find all these volumes. Therefore a filter excluding these device is not the solution. But I dislike all my drives spinning up and having to wait for that when I simply call vgdisplay vg0 to see how much space is left in my primary volume group with /, /usr, /var and /home file systems, which are active all time. Steve
