mogilefs file.devcount

[Brad Fitzpatrick]

Robin H. Johnson wrote:
> Heya,
>
> Reviewing code, is the file.devcount field supposed to be dead or not?
>
> Only the SQLite store documentation makes comments to that effect, but
> the stats command still seems to actively use it, and it's curiously
> missing in other places.
>
>   
It's on its way out.

It's not used for anything nowadays except for "old_repl_compat", where 
you use pre-2.x mogilefsd in conjunction with post-2.x mogilefsd, which 
isn't really recommended anyway.  Plus the old_repl_compat code doesn't 
really work that well, reportedly, wasting a lot of CPU.

Yet the code still tries to maintain it.  Yes, stats also uses it, but 
there's no reason it has to.  The stats code is crap and was a quick 
hack back in the day... it doesn't scale at all, and I think it locks 
the whole database up for a bunch of time too.  I have a plan to redo it.

So basically, for the Postgres stuff, I'd just totally ignore updating 
the devcount stuff.  Given that 1.x can't work with Pg anyway, 
old_repl_compat will never be used, and there's no point to file.devcount.

If you want, I'd even accept a patch to rip out old_repl_compat and 
devcount updating globally, as long as the CHANGES file loudly yells 
that it's no longer supported.

- Brad