Hi Ulrich,
On Tue, Mar 15, 2016 at 9:00 AM, Ulrich Windl Ulrich.Windl@rz.uni-regensburg.de wrote:
Arto Bendiken arto@bendiken.net schrieb am 14.03.2016 um 17:30 in Nachricht
CAE7aNuS4=5ENrgL7w=zDqUe2dE7WH01nkAkAX76Msuw_uj=xug@mail.gmail.com:
Here's a curious case that I had not encountered with LMDB as yet previously:
- There was a power reset of a virtual machine with an active LMDB
writer process (standalone use, not OpenLDAP) on an LMDB file containing three sub-DBs.
[...]
Hi!
What is a "power reset of a virtual machine"? A virtual power reset (i.e. reset), or a power reset of the host? In the latter case some writes that the VM considers done may not be committed on the host, depending on the exact configuration. You didn't give any details on that, so I can only guess...
The latter, with the VM's virtio disks being LVM volumes assigned and dedicated to it using libvirt--a run-of-the-mill configuration.
Hi,
On Tue, 15 Mar 2016, Arto Bendiken wrote:
What is a "power reset of a virtual machine"? A virtual power reset (i.e. reset), or a power reset of the host? In the latter case some writes that the VM considers done may not be committed on the host, depending on the exact configuration. You didn't give any details on that, so I can only guess...
The latter, with the VM's virtio disks being LVM volumes assigned and dedicated to it using libvirt--a run-of-the-mill configuration.
LVM does an extremely bad job of properly implementing write barriers so you can achieve an inconsitent state that is hard to recover from.
Greetings Christian
openldap-technical@openldap.org
-
Arto Bendiken -
Christian Kratzer