Re: [PATCH] pack-bitmap: remove trace2 region from hot path

From: Taylor Blau <me@ttaylorr.com>
Date: Sep 23, 2022, 19:17 UTC
Message-ID: <Yy4GVT8VZ4dOyGDy@nand.local>
In-Reply-To: <xmqq7d1uuh5f.fsf@gitster.g>

On Fri, Sep 23, 2022 at 10:36:44AM -0700, Junio C Hamano wrote:

Show 13 quoted lines

> diff --git c/t/t5310-pack-bitmaps.sh w/t/t5310-pack-bitmaps.sh
> index 7e50f8e765..2b1efc923b 100755
> --- c/t/t5310-pack-bitmaps.sh
> +++ w/t/t5310-pack-bitmaps.sh
> @@ -455,7 +455,7 @@ test_expect_success 'verify writing bitmap lookup table when enabled' '
>  	grep "\"label\":\"writing_lookup_table\"" trace2
>  '
>
> -test_expect_success 'lookup table is actually used to traverse objects' '
> +: test_expect_success 'lookup table is actually used to traverse objects' '
>  	git repack -adb &&
>  	GIT_TRACE2_EVENT="$(pwd)/trace3" \
>  		git rev-list --use-bitmap-index --count --all &&

Yeah, I would advocate for dropping this test entirely. That trace2 marker is the only indication that is so obvious that we're using the lookup table to read bitmaps.

Perhaps the pack-bitmap helper could be taught to dump which extensions it sees, and then write a test based on that? Although that isn't really testing anything new, either, since we sometimes *notice* the extension but don't actually read anything based on it (e.g., when disabled).

So I'd be content just dropping this.

Thanks, Taylor