From mboxrd@z Thu Jan  1 00:00:00 1970
From: Jeff King <peff@peff.net>
Subject: Re: [PATCH 2/2] pkt-line: show packets in async processes as
 "sideband"
Date: Tue, 1 Sep 2015 18:38:08 -0400
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Cc: Junio C Hamano <gitster@pobox.com>,
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To: Stefan Beller <sbeller@google.com>
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On Tue, Sep 01, 2015 at 03:31:41PM -0700, Stefan Beller wrote:

> > Ah, right, I think I misunderstood Junio's question. Yes, if we start
> > calling cmd_fetch() from inside the threads, things may get confusing.
> >
> > I'll see how painful the thread storage approach would be.
> 
> I think that may be part of the thread pool API eventually.
> 
> I don't plan on relying on thread local storage, which is why I did
> not add it there,
> though I guess it can be added in there quite conveniently.

I think the task_queue and the async code are two separate things,
though. The task_queue, when we do not have threads, falls back to doing
things serially in a single process. Changing "thread local" variables
there is OK, but tasks need to be aware that they might affect
subsequent tasks.

Whereas for async code, we fall back to doing things in a forked
sub-process. And there "thread local" really is local to the async
process, no cleanup required.

-Peff