Re: [PATCH] t7900: speed up expensive test

[Derrick Stolee <stolee@gmail.com>]

On 12/1/2020 9:47 PM, Jeff King wrote:
> Subject: [PATCH] t7900: speed up expensive test
> 
> A test marked with EXPENSIVE creates two 2.5GB files and adds them to
> the repository. This takes 194s to run on my machine, versus 2s when the
> EXPENSIVE prereq isn't set. We can trim this down a bit by doing two
> things:
> 
>   - use "git commit --quiet" to avoid spending time generating a diff
>     summary (this actually only helps for the second commit, but I've
>     added it here to both for consistency). This shaves off 8s.
> 
>   - set core.compression to 0. We know these files are full of random
>     bytes, and so won't compress (that's the point of the test!).
>     Spending cycles on zlib is pointless. This shaves off 122s.
> 
> After this, my total time to run the script is 64s. That won't help
> normal runs without GIT_TEST_LONG set, of course, but it's easy enough
> to do.

I'm happy with these easy fixes to make the test faster without
changing any of the important behavior. Thanks!

> Signed-off-by: Jeff King <peff@peff.net>
> ---
>  t/t7900-maintenance.sh | 6 ++++--
>  1 file changed, 4 insertions(+), 2 deletions(-)
> 
> diff --git a/t/t7900-maintenance.sh b/t/t7900-maintenance.sh
> index d9e68bb2bf..d9a02df686 100755
> --- a/t/t7900-maintenance.sh
> +++ b/t/t7900-maintenance.sh
> @@ -239,13 +239,15 @@ test_expect_success 'incremental-repack task' '
>  '
>  
>  test_expect_success EXPENSIVE 'incremental-repack 2g limit' '
> +	test_config core.compression 0 &&
> +
>  	for i in $(test_seq 1 5)
>  	do
>  		test-tool genrandom foo$i $((512 * 1024 * 1024 + 1)) >>big ||
>  		return 1
>  	done &&
>  	git add big &&
> -	git commit -m "Add big file (1)" &&
> +	git commit -qm "Add big file (1)" &&
>  
>  	# ensure any possible loose objects are in a pack-file
>  	git maintenance run --task=loose-objects &&
> @@ -257,7 +259,7 @@ test_expect_success EXPENSIVE 'incremental-repack 2g limit' '
>  		return 1
>  	done &&
>  	git add big &&
> -	git commit -m "Add big file (2)" &&
> +	git commit -qm "Add big file (2)" &&
>  
>  	# ensure any possible loose objects are in a pack-file
>  	git maintenance run --task=loose-objects &&
>