Re: [PATCH] commit: don't rewrite shared index unnecessarily

From: Duy Nguyen <pclouds@gmail.com>
Date: Aug 31, 2015, 10:02 UTC
Message-ID: <CACsJy8D=KyWBYf1LW=n928rmG=9xavSaR+1G1g+F7mMTKFCpfg@mail.gmail.com>
In-Reply-To: <1440695274-12400-1-git-send-email-dturner@twopensource.com>

On Fri, Aug 28, 2015 at 12:07 AM, David Turner <dturner@twopensource.com> wrote:

Show 14 quoted lines

> Remove a cache invalidation which would cause the shared index to be
> rewritten on as-is commits.
>
> When the cache-tree has changed, we need to update it.  But we don't
> necessarily need to update the shared index.  So setting
> active_cache_changed to SOMETHING_CHANGED is unnecessary.  Instead, we
> let update_main_cache_tree just update the CACHE_TREE_CHANGED bit.
>
> In order to test this, make test-dump-split-index not segfault on
> missing replace_bitmap/delete_bitmap.  This new codepath is not called
> now that the test passes, but is necessary to avoid a segfault when the
> new test is run with the old builtin/commit.c code.
>
> Signed-off-by: David Turner <dturner@twopensource.com>

Ack.

I made SOMETHING_CHANGED "1" for catching these cases (there were a few on-flight topics when this series was being cooked and I was afraid I could not cache all active_cache_changed sites).

Show 5 quoted lines

> ---
>
> I introduced this bug last year while improving the cache-tree code.
> I guess I probably didn't notice that active_cache_changed wasn't a
> boolean.

So.. you did you split-index? Cool. Never heard anyone using it for real. It needs the other part to improve reading/refresh side to get to full potential though..

-- 
Duy