[linux-lvm] Discussion: performance issue on event activation mode

[Martin Wilck]

On So, 2021-06-06 at 14:15 +0800, heming.zhao at suse.com wrote:
> 
> 1. During boot phase, lvm2 automatically swithes to direct activation
> mode
> ("event_activation = 0"). After booted, switch back to the event
> activation mode.
> 
> Booting phase is a speical stage. *During boot*, we could "pretend"
> that direct
> activation (event_activation=0) is set, and rely on lvm2-activation-
> *.service
> for PV detection. Once lvm2-activation-net.service has finished, we
> could
> "switch on" event activation.

I like this idea. Alternatively, we could discuss disabling event
activation only in the "coldplug" phase after switching root (i.e.
between start of systemd-udev-trigger.service and lvm2-
activation.service), because that's the critical time span during which
1000s of events can happen simultaneously.

Regards
Martin