[PATCH 4 of 4 V2] chgserver: start background preloading thread

[Yuya Nishihara]

On Wed, 22 Feb 2017 18:16:11 -0800, Jun Wu wrote:
> # HG changeset patch
> # User Jun Wu <quark at fb.com>
> # Date 1487814470 28800
> #      Wed Feb 22 17:47:50 2017 -0800
> # Node ID 5c44925eab9a424369967e852b05f42443eac3a6
> # Parent  28571825744fb4f4b424385f55afa9484532ef43
> # Available At https://bitbucket.org/quark-zju/hg-draft
> #              hg pull https://bitbucket.org/quark-zju/hg-draft -r 5c44925eab9a
> chgserver: start background preloading thread
> 
> A new boolean option chgserver.stateful is added. If set to True, chg master
> will start the background repo preloading thread and becomes stateful.
> 
> diff --git a/mercurial/chgserver.py b/mercurial/chgserver.py
> --- a/mercurial/chgserver.py
> +++ b/mercurial/chgserver.py
> @@ -37,4 +37,7 @@ Config
>    # whether to skip config or env change checks
>    skiphash = False
> +
> +  # whether to be stateful, and preload repo state in background
> +  stateful = False
>  """

Let's keep it undocumented for now.

> @@ -582,4 +585,26 @@ class chgunixservicehandler(object):
>                              self._hashstate, self._baseaddress)
>  
> +class chgunixforkingservice(commandserver.unixforkingservice):
> +    """like unixforkingservice with an optional chgcache.preloader"""
> +
> +    def __init__(self, ui, repo, opts, handler=None):
> +        super(chgunixforkingservice, self).__init__(ui, repo, opts, handler)
> +        if self.ui.configbool('chgserver', 'stateful'):
> +            self._preloader = chgcache.preloader()
> +        else:
> +            self._preloader = None
> +
> +    def init(self):
> +        super(chgunixforkingservice, self).init()
> +        if self._preloader is not None:
> +            self.ui.debug('starting background preloader\n')
> +            self._preloader.start()
> +
> +    def _cleanup(self):
> +        super(chgunixforkingservice, self)._cleanup()
> +        if self._preloader is not None:
> +            self.ui.debug('stopping background preloader\n')
> +            self._preloader.stop()

Can you add a couple of hooks to chgunixservicehandler to isolate chg stuff
from the service class?