From: David Teigland <teigland@redhat.com>
To: Martin Wilck <martin.wilck@suse.com>
Cc: "zkabelac@redhat.com" <zkabelac@redhat.com>,
"linux-lvm@redhat.com" <linux-lvm@redhat.com>,
Heming Zhao <heming.zhao@suse.com>
Subject: Re: [linux-lvm] Discussion: performance issue on event activation mode
Date: Mon, 7 Jun 2021 16:48:35 -0500 [thread overview]
Message-ID: <20210607214835.GB8181@redhat.com> (raw)
In-Reply-To: <d1d35f7dba3d0e887e7eac06a06ff2414a84c924.camel@suse.com>
On Mon, Jun 07, 2021 at 03:48:30PM +0000, Martin Wilck wrote:
> On So, 2021-06-06 at 14:15 +0800, heming.zhao@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.
If there are say 1000 PVs already present on the system, there could be
real savings in having one lvm command process all 1000, and then switch
over to processing uevents for any further devices afterward. The switch
over would be delicate because of the obvious races involved with new devs
appearing, but probably feasible. I'd like to see the scale of
improvement from a proof of concept before we spend too much time on the
details.
Dave
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next prev parent reply other threads:[~2021-06-07 21:48 UTC|newest]
Thread overview: 86+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-06-06 6:15 [linux-lvm] Discussion: performance issue on event activation mode heming.zhao
2021-06-06 16:35 ` Roger Heflin
2021-06-07 10:27 ` Martin Wilck
2021-06-07 15:30 ` heming.zhao
2021-06-07 15:45 ` Martin Wilck
2021-06-07 20:52 ` Roger Heflin
2021-06-07 21:30 ` David Teigland
2021-06-08 8:26 ` Martin Wilck
2021-06-08 15:39 ` David Teigland
2021-06-08 15:47 ` Martin Wilck
2021-06-08 16:02 ` Zdenek Kabelac
2021-06-08 16:05 ` Martin Wilck
2021-06-08 16:03 ` David Teigland
2021-06-08 16:07 ` Martin Wilck
2021-06-15 17:03 ` David Teigland
2021-06-15 18:21 ` Zdenek Kabelac
2021-06-16 16:18 ` heming.zhao
2021-06-16 16:38 ` David Teigland
2021-06-17 3:46 ` heming.zhao
2021-06-17 15:27 ` David Teigland
2021-06-08 16:49 ` heming.zhao
2021-06-08 16:18 ` heming.zhao
2021-06-09 4:01 ` heming.zhao
2021-06-09 5:37 ` Heming Zhao
2021-06-09 18:59 ` David Teigland
2021-06-10 17:23 ` heming.zhao
2021-06-07 15:48 ` Martin Wilck
2021-06-07 16:31 ` Zdenek Kabelac
2021-06-07 21:48 ` David Teigland [this message]
2021-06-08 12:29 ` Peter Rajnoha
2021-06-08 13:23 ` Martin Wilck
2021-06-08 13:41 ` Peter Rajnoha
2021-06-08 13:46 ` Zdenek Kabelac
2021-06-08 13:56 ` Peter Rajnoha
2021-06-08 14:23 ` Zdenek Kabelac
2021-06-08 14:48 ` Martin Wilck
2021-06-08 15:19 ` Peter Rajnoha
2021-06-08 15:39 ` Martin Wilck
2021-09-09 19:44 ` David Teigland
2021-09-10 17:38 ` Martin Wilck
2021-09-12 16:51 ` heming.zhao
2021-09-27 10:00 ` Peter Rajnoha
2021-09-27 15:38 ` David Teigland
2021-09-28 6:34 ` Martin Wilck
2021-09-28 14:42 ` David Teigland
2021-09-28 15:16 ` Martin Wilck
2021-09-28 15:31 ` Martin Wilck
2021-09-28 15:56 ` David Teigland
2021-09-28 18:03 ` Benjamin Marzinski
2021-09-28 17:42 ` Benjamin Marzinski
2021-09-28 19:15 ` Martin Wilck
2021-09-29 22:06 ` Peter Rajnoha
2021-09-30 7:51 ` Martin Wilck
2021-09-30 8:07 ` heming.zhao
2021-09-30 9:31 ` Martin Wilck
2021-09-30 11:41 ` Peter Rajnoha
2021-09-30 15:32 ` heming.zhao
2021-10-01 7:41 ` Martin Wilck
2021-10-01 8:08 ` Peter Rajnoha
2021-09-30 11:29 ` Peter Rajnoha
2021-09-30 16:04 ` David Teigland
2021-09-30 14:41 ` Benjamin Marzinski
2021-10-01 7:42 ` Martin Wilck
2021-09-29 21:53 ` Peter Rajnoha
2021-09-30 7:45 ` Martin Wilck
2021-09-29 21:39 ` Peter Rajnoha
2021-09-30 7:22 ` Martin Wilck
2021-09-30 14:26 ` David Teigland
2021-09-30 15:55 ` David Teigland
2021-10-01 8:00 ` Peter Rajnoha
2021-10-18 6:24 ` Martin Wilck
2021-10-18 15:04 ` David Teigland
2021-10-18 16:56 ` heming.zhao
2021-10-18 21:51 ` Zdenek Kabelac
2021-10-19 17:18 ` David Teigland
2021-10-20 14:40 ` Martin Wilck
2021-10-20 14:50 ` David Teigland
2021-10-20 14:54 ` Martin Wilck
2021-10-20 15:12 ` David Teigland
2021-06-07 16:40 ` David Teigland
2021-07-02 21:09 ` David Teigland
2021-07-02 21:22 ` Martin Wilck
2021-07-02 22:02 ` David Teigland
2021-07-03 11:49 ` heming.zhao
2021-07-08 10:10 ` Tom Yan
2021-07-02 21:31 ` Tom Yan
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