[Gluster-devel] GF_FOP_IPC changes

[Soumya Koduri]

On 06/29/2015 08:18 PM, Niels de Vos wrote:
> On Wed, Jun 24, 2015 at 07:44:13PM +0530, Soumya Koduri wrote:
>>
>>
>> On 06/24/2015 10:14 AM, Krishnan Parthasarathi wrote:
>>>
>>>
>>> ----- Original Message -----
>>>> I've been looking at the recent patches to redirect GF_FOP_IPC to an active
>>>> subvolume instead of always to the first.  Specifically, these:
>>>>
>>>>     http://review.gluster.org/11346 for DHT
>>>>     http://review.gluster.org/11347 for EC
>>>>     http://review.gluster.org/11348 for AFR
>>>>
>>>> I can't help but wonder if there's a simpler and more generic way to do this,
>>>> instead of having to do this in a translator-specific way each time - then
>>>> again for NSR, or for a separate tiering translator, and so on.  For example
>>>> what if each translator had a first_active_child callback?
>>>>
>>>>     xlator_t * (*first_active_child) (xlator_t *parent);
>>>>
>>>> Then default_ipc could invoke this, if it exists, where it currently invokes
>>>> FIRST_CHILD.  Each translator could implement a bare minimum to select a
>>>> child, then "step out of the way" for a fop it really wasn't all that
>>>> interested in to begin with.  Any thoughts?
>>>
>>> We should do this right away. This change doesn't affect external interfaces.
>>> we should be bold and implement the first solution. Over time we could improve
>>> on this.
>>
>> +1. It would definitely ease the implementation of many such fops which have
>> to default to first active child. We need not keep track of all the fops
>> which may get affected with new clustering xlators being added.
>
> I think it is a great improvement and makes the code much easier to
> understand. Do we have a volunteer that wants to have a go at
> implementing this?
>
I volunteer. Pranith already seem to have some thoughts on it. I shall 
check with him and update the initial findings.

Thanks,
Soumya

> Thanks,
> Niels
>