[Lustre-discuss] sync_journal

[Andreas Dilger]

On 2010-05-21, at 12:35, Kit Westneat wrote:
> I'm surprised you can't set this via conf_param. What parameter name did you try? Also, in bugzilla Nathan has patches to change conf_param syntax to match the {get,set,list}_param syntax so that it is easier to set permanent tunables.
> 
>> I'd think (without having tried it) that:
>> 
>> lctl conf_param {fsname}.obdfilter.sync_journal=0
>>   
> 
> That's the first one I tried :-) BTW, conf_param doesn't fail nicely. If you all are revisiting it, it would be nice to get some output on stderr that it's failed.

Yes, that is more tricky than it sounds, because the MGS is doing the conf_param, but it is taking settings for the MDS and OSS and client nodes, and it has no way of knowing whether the parameter is correct or not.

The other good thing about Nathan's patches is the ability to delete conf_param settings.  While not as good as actual feedback in case of error, at least it allows cleaning up mistakes.

> I also tried every other way that I could think of to do it. Are the conf_param patches scheduled to be in 1.8.4? You don't happen to have the ticket # handy do you?

Bug 17471 "set_param and conf_param have different syntaxes" is one of them.  I'm not sure what release they are slated for.

Cheers, Andreas
--
Andreas Dilger
Lustre Technical Lead
Oracle Corporation Canada Inc.