Gluster users - May 2015 - performance tuning - list of available options?

On Tue, 2015-05-05 at 15:08 +0530, Vijay Bellur wrote:
[snip] 
> I have seen this before and it primarily seems to be related to the 
> readdir calls done by git clone.
> 
> Turning on these options might help to some extent:
> 
> gluster volume set <volname> performance.readdir-ahead on
> 
> gluster volume set <volname> cluster.readdir-optimize on
Is there a list of all performance tuning options, and a description of
what they do? Even better if it details pros/cons of using a particular
option, or circumstances in which you might want to use it.

If such a list exists, it would be very useful. I've tried googling but
can only find pages for very old versions (eg gluster 3.2) and only
detailing /some/ options.

Knowing what the value defaults to would also be handy. In a separate
thread, someone advised me to do "gluster volume set <VOLNAME>
performance.flush-behind off", but when I found that didn't help (the
issue turned out to be something I was doing, not a fault in gluster) I
couldn't figure out what the default value was, so I didn't know whether
to leave it off, or whether it had previously been on.

Is there anything available?

-- 
Cheers,
Kingsley.

On 05/05/2015 04:34 PM, Kingsley wrote:
> On Tue, 2015-05-05 at 15:08 +0530, Vijay Bellur wrote:
> [snip]
>> I have seen this before and it primarily seems to be related to the
>> readdir calls done by git clone.
>>
>> Turning on these options might help to some extent:
>>
>> gluster volume set <volname> performance.readdir-ahead on
>>
>> gluster volume set <volname> cluster.readdir-optimize on
>
> Is there a list of all performance tuning options, and a description of
> what they do? Even better if it details pros/cons of using a particular
> option, or circumstances in which you might want to use it.
>
> If such a list exists, it would be very useful. I've tried googling but
> can only find pages for very old versions (eg gluster 3.2) and only
> detailing /some/ options.
>
> Knowing what the value defaults to would also be handy. In a separate
> thread, someone advised me to do "gluster volume set <VOLNAME>
> performance.flush-behind off", but when I found that didn't help
(the
> issue turned out to be something I was doing, not a fault in gluster) I
> couldn't figure out what the default value was, so I didn't know
whether
> to leave it off, or whether it had previously been on.
>
> Is there anything available?

Thanks for this feedback. This is something that I would like to see 
captured too.

Raghavendra, Rafi - would you be able to help create a document on this one?

-Vijay