samba - Jul 2016 - Winbind process stuck at 100% after changing use_mmap to no

On 04/07/16 20:39, Volker Lendecke wrote:
> On Mon, Jul 04, 2016 at 04:58:35PM +0100, Alex Crow wrote:
>> • Add the following lines to the [global] section of your Samba
>> configuration
>> clustering = yes
>> idmap backend = tdb2
>> private dir = /gluster/lock
>>
>> Can you confirm that "private dir" does *not* have to be set
in smb.conf to
>> point to a shared FS? If not, would that solve the original problem?
> No, it does not have to be set. In fact, it is very likely harmful.
> ctdb determines where the clustered dbs are located, not samba.
>
> Volker
HI Volker,

I've set up the "DR" side of my cluster to "use mmap =
no" and with
"private dir" removed from the smb.conf.

However I still have huge CPU utilisation from winbindd and smbd just
fromtrying to long in a single test XP machine.

I have the MooseFS guys on the case as well. Should I put them in touch
with you or vice/versa?

Many thanks for your gracious assistance,

Alex

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On Tue, Jul 05, 2016 at 07:21:16PM +0100, Alex Crow
wrote:
> I've set up the "DR" side of my cluster to "use mmap =
no" and with
> "private dir" removed from the smb.conf.
Why do you set "use mmap = no"?
> I have the MooseFS guys on the case as well. Should I put them in touch
> with you or vice/versa?
MooseFS should not have any business at all in tdb files. If you still
find tdb files used on MooseFS, you should investigate your
configuration and modify it such that tdb files only exist on local
file systems.

Volker

On 05/07/16 19:45, Volker Lendecke wrote:
> On Tue, Jul 05, 2016 at 07:21:16PM +0100, Alex Crow wrote:
>> I've set up the "DR" side of my cluster to "use mmap
= no" and with
>> "private dir" removed from the smb.conf.
> Why do you set "use mmap = no"?
>
>> I have the MooseFS guys on the case as well. Should I put them in touch
>> with you or vice/versa?
> MooseFS should not have any business at all in tdb files. If you still
> find tdb files used on MooseFS, you should investigate your
> configuration and modify it such that tdb files only exist on local
> file systems.
>
> Volker
Hi Volker,

There are *no* more tdb files on MooseFS, that's what I'm trying to
test.

From the ping_pong wiki page it's instructed to use "use_mmap =
no" if
the ping_pong test does not work correctly on "ping_ping -m -rw
test.file", which it did, completely.

Text here:

"


    Testing mmap coherence

If you add the -m switch to ping_pong along with -rw then it will do the
I/O coherence test via mmap. It isn't absolutely essential that a
cluster filesystem supports coherent mmap for CTDB/Samba, but it's nice
for bragging points over other cluster filesystems. If your cluster
filesystem doesn't pass this test then just use the "use mmap =
no"
option in smb.conf. Even if it does pass this test that option may be a
good idea on most cluster filesystems."


So is this documentation wrong as well? It seems to suggest setting it
anyway, which is clearly not working for us (and now for sure there is
no involvement with TDB files as I've deleted the "private dir" in
smb.conf.


The only reason I was asking if you'd like to talk to the MooseFS chaps
is because of the failure of the -rw test, which as far as the
documentation goes, seems to refer to the shared FS rather than any
places where tdb files live.

I hope you can see what I'm getting at here!

Many thanks

Alex




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The information provided is correct to our knowledge & belief and must not
be used as a substitute for obtaining tax, regulatory, investment, legal or
any other appropriate advice.

"Transact" is operated by Integrated Financial Arrangements Ltd.
29 Clement's Lane, London EC4N 7AE. Tel: (020) 7608 4900 Fax: (020) 7608
5300.
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number: 3727592). Authorised and regulated by the Financial Conduct
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