Re: [PATCH v2 2/3] read-cache: load cache extensions on worker thread

From: Duy Nguyen <pclouds@gmail.com>
Date: Sep 3, 2018, 19:27 UTC
Message-ID: <CACsJy8Dm-jRYfp1UVu8O+NiHf61RVY5t1vvsbXan0YrhsDabbA@mail.gmail.com>
In-Reply-To: <CACsJy8AC8VT=DEcmqAtW26pYKRVT1Kz=pVyj-Wnu3uOsKwWGTw@mail.gmail.com>

On Mon, Sep 3, 2018 at 9:21 PM Duy Nguyen <pclouds@gmail.com> wrote:

Show 12 quoted lines

> > I used p0002-read-cache.sh to generate some performance data on the
> > cumulative impact:
> >
> > 100,000 entries
> >
> > Test                                HEAD~3           HEAD~2
> > ---------------------------------------------------------------------------
> > read_cache/discard_cache 1000 times 14.08(0.01+0.10) 9.72(0.03+0.06) -31.0%
>
> This is misleading (if I read it correctly). 1/3 already drops
> execution time down to 9.81, so this patch alone only has about 6%
> saving.

I may have miscalculated that. 1/3 says -30% saving, here it's -31%, so I guess it's 1% extra saving (or ~3% on 1m entries)? That's definitely not worth doing.

-- 
Duy