[Ocfs2-users] OCFS2 and berkeley database files

[Eckenfels. Bernd]

However, in the specific case it would be enough to allow the shared
write on a single system, which could be easyly allowed. 

-----Original Message-----
From: ocfs2-users-bounces at oss.oracle.com
[mailto:ocfs2-users-bounces at oss.oracle.com] On Behalf Of Alexei_Roudnev
Sent: Thursday, December 07, 2006 2:39 AM
To: Sunil Mushran
Cc: Michael Wood; ocfs2-users at oss.oracle.com
Subject: Re: [Ocfs2-users] OCFS2 and berkeley database files

Many sources are saying, that maintaining syncronzied memory (mmap to
the same area == you must syncronized shared memory between 2 servers)
is not a trivial task. Oracle is doing it inside RAC luster for some
objects only, using CSSD.

shared/writable mmap means that I can run 2 processes, one on host1 and
second on host2, and have shared memory which is exactly the same on
both servers all the time (for the local host, it is implemented by
mapping file to THE SAME physical memory). This task have not a clean
solution in the general case.


----- Original Message -----
From: "Sunil Mushran" <Sunil.Mushran at oracle.com>
To: "Alexei_Roudnev" <Alexei_Roudnev at exigengroup.com>
Cc: <hartmut.woehrle at mail.pcom.de>; "Michael Wood"
<michael.wood at uct.ac.za>; <ocfs2-users at oss.oracle.com>
Sent: Wednesday, December 06, 2006 4:41 PM
Subject: Re: [Ocfs2-users] OCFS2 and berkeley database files


> Who said it was impossible across servers?
>
> Alexei_Roudnev wrote:
> > I can understand BerkleyDB, but why LDAP use shared/writable mmap?
> >
> > PS. How do you manage to implement shared writeble mmap in OCFSv2 if
it's
> > almost impossible between the servers? /Just curious/
> >
> >
> > ----- Original Message ----- 
> > From: "Sunil Mushran" <Sunil.Mushran at oracle.com>
> > To: "Alexei_Roudnev" <Alexei_Roudnev at exigengroup.com>
> > Cc: <hartmut.woehrle at mail.pcom.de>; "Michael Wood"
<michael.wood at uct.ac.za>;
> > <ocfs2-users at oss.oracle.com>
> > Sent: Wednesday, December 06, 2006 1:47 PM
> > Subject: Re: [Ocfs2-users] OCFS2 and berkeley database files
> >
> >
> >
> >> ocfs2 supports private mmap r/w and shared mmap readonly.
> >> Shared mmap writeable is the only piece missing. We should have
that by
> >>
> > 1.4.
> >
> >> Alexei_Roudnev wrote:
> >>
> >>> There was a clear answer, WHY it did not worked on OCFSv2:
> >>>
> >>> - BerkleyDB and LDAP uses mmap to the files;
> >>> - OCFSv2 don't implement it (because it is not possible to do such
> >>>
> > mapping
> >
> >>> in the cluster FS)
> >>> - So they dont work on OCFSv2
> >>>
> >>> Am I correct?
> >>>
> >>> ----- Original Message ----- 
> >>> From: <hartmut.woehrle at mail.pcom.de>
> >>> To: "Michael Wood" <michael.wood at uct.ac.za>
> >>> Cc: <ocfs2-users at oss.oracle.com>
> >>> Sent: Wednesday, December 06, 2006 2:33 AM
> >>> Subject: Re: [Ocfs2-users] OCFS2 and berkeley database files
> >>>
> >>>
> >>> Am Mi, 6.12.2006, 09:35, schrieb Michael Wood:
> >>>
> >>>
> >>>
> >>>> Berkeley DB does have problems with certain filesystems (e.g.
> >>>> NFS) so maybe this is a similar issue.  (Just a wild guess.)
> >>>>
> >>>>
> >>>>
> >>> Yes I found the Orcale FAQ. So it is s structural problem with a
> >>>
> > "simple"
> >
> >>> DB and then trying to open it more than once
> >>>
> >>>
> >>>
> >>>
> >>>> OpenLDAP supports various different backends.  Maybe one of the
> >>>> others will work better?
> >>>>
> >>>>
> >>>>
> >>> Perhaps, but my guess is, that the funktionality of an cluster
> >>>
> > filesystem
> >
> >>> always uses an access to every file, even if it is not connected
to a
> >>> service. So I think it will not work if theses files are not able
to
> >>> handle more than one access at one time.
> >>>
> >>>
> >>>
> >>>> Cyrus also supports various different database types for its
> >>>> databases.  Maybe try one of the others.  I have never used
either
> >>>>
> >>>>
> >>> OpenLDAP
> >>>
> >>>
> >>>> or Cyrus on ocfs2, so I can't guarantee anything :)
> >>>>
> >>>>
> >>> Same as above
> >>>
> >>>
> >>>
> >>>>> Server is a DELL Poweredge with EMC CLARiiON SAN
> >>>>> System SuSE SLES9 SP3+
> >>>>> ->  2.6.5-7.244-smp Kernel with (...> modinfo ocfs2):
> >>>>> license:        GPL
> >>>>> author:         Oracle
> >>>>> version:        1.1.7-SLES 5AF01E6455FC04917FE52FB
> >>>>> description:    OCFS2 1.1.7-SLES Tue Nov  1 14:45:27 PST 2005
(build
> >>>>> sles) depends:        ocfs2_nodemanager,ocfs2_dlm,jbd
> >>>>> supported:      yes
> >>>>> vermagic:       2.6.5-7.244-smp SMP gcc-3.3
> >>>>>
> >>>>>
> >>>>>
> >>>> [snip]
> >>>>
> >>>>
> >>>> 2.6.5-7.244 was released with SLES9 SP3.  You might want to
> >>>> patch your box to 2.6.5-7.282 (which I think is the latest.)
> >>>>
> >>>> The 7.282 version of the SLES9 SP3 kernel comes with ocfs2
> >>>> version 1.2.1-SLES.
> >>>>
> >>>>
> >>> Yes, but this EMC multipath software installs some kernelmodules
> >>> (binaries, no sources) and they only match with the kernels in the
list.
> >>> So I have to wait for the next release :(((
> >>>
> >>>
> >>>
> >>>> On the ocfs2 homepage it says:
> >>>>
> >>>>
> >>>> SuSE Linux Exterprise Server 9: OCFS2 1.2.1 is bundled
> >>>> with the SLES9 SP3 (2.6.5-7.257 and later) release. SLES9 users
must
> >>>> upgrade to the latest SP3 kernel (2.6.5-7.257 or later) and
install
> >>>> ocfs2-tools and ocfs2console packages. For more on OCFS2 bundling
with
> >>>> SLES9, refer to the Novell SLES9 section in the FAQ
> >>>>
> >>>>
> >>>>
> >>> See above
> >>>
> >>>
> >>>
> >>>> --
> >>>> Michael Wood <michael.wood at uct.ac.za>
> >>>>
> >>>>
> >>>>
> >>>>
> >>>
> >>> _______________________________________________
> >>> Ocfs2-users mailing list
> >>> Ocfs2-users at oss.oracle.com
> >>> http://oss.oracle.com/mailman/listinfo/ocfs2-users
> >>>
> >>>
> >>> _______________________________________________
> >>> Ocfs2-users mailing list
> >>> Ocfs2-users at oss.oracle.com
> >>> http://oss.oracle.com/mailman/listinfo/ocfs2-users
> >>>
> >>>
> >
> >
>


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