On Mon, 27 Jun 2011, Jan Kara wrote: > On Mon 27-06-11 13:16:50, Lukas Czerner wrote: > > On Fri, 24 Jun 2011, Jan Kara wrote: > > > > > On Fri 24-06-11 11:03:52, Moffett, Kyle D wrote: > > > > On Jun 24, 2011, at 09:46, Jan Kara wrote: > > > > > On Thu 23-06-11 16:19:08, Moffett, Kyle D wrote: > > > > >> Besides which, line 534 in the Debian 2.6.32 kernel I am using is this > > > > >> one: > > > > >> > > > > >> J_ASSERT(commit_transaction->t_nr_buffers <= > > > > >> commit_transaction->t_outstanding_credits); > > > > > > > > > > Hmm, OK, so we've used more metadata buffers than we told JBD2 to > > > > > reserve. I suppose you are not using data=journal mode and the filesystem > > > > > was created as ext4 (i.e. not converted from ext3), right? Are you using > > > > > quotas? > > > > > > > > The filesystem *is* using data=journal mode. If I switch to data=ordered > > > > or data=writeback, the problem goes away. > > > Ah, OK. Then bug https://bugzilla.kernel.org/show_bug.cgi?id=34642 is > > > probably ext3 incarnation of the same problem and it seems it's still > > > present even in the current kernel - that ext3 assertion triggered even > > > with 2.6.39 kernel. Frankly data=journal mode is far less tested than the > > > other two modes especially with ext4, so I'm not sure how good idea is to > > > use it in production. > > Hi Lukas, > > > if it is so (and it probably is, since I am not testing this mode as > > well:), it would be interesting to find out whether there are many users > > of this and if there are not, which is probably the case, deprecate it now, > > so we can remove it later. If we are openly suggesting not to use this, > > then there is probably no point in having this option in the first > > place. > For about one year I'm trying to look for people using data=journal and > I've found some. So although data=journal users are minority, there are > some. That being said I agree with you we should do something about it > - either state that we want to fully support data=journal - and then we > should really do better with testing it or deprecate it and remove it > (which would save us some complications in the code). > > I would be slightly in favor of removing it (code simplicity, less options > to configure for admin, less options to test for us, some users I've come > across actually were not quite sure why they are using it - they just > thought it looks safer). > > Honza > I completely agree with you. Also I find it really dangerous that the option which looks much safer is in fact less safe, because just a minority of people (including developers) are testing it. Thanks! -Lukas -- To unsubscribe from this list: send the line "unsubscribe linux-ext4" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
