On Thu, Sep 19, 2019 at 10:15 AM Jeff Hostetler via GitGitGadget
<gitgitgadget@xxxxxxxxx> wrote:
>
> From: Jeff Hostetler <jeffhost@xxxxxxxxxxxxx>
>
> When Git updates the working directory with the sparse-checkout
> feature enabled, the unpack_trees() method calls clear_ce_flags()
> to update the skip-wortree bits on the cache entries. This
> check can be expensive, depending on the patterns used.
>
> Add trace2 regions around the method, including some flag
> information, so we can get granular performance data during
> experiments. This data will be used to measure improvements
> to the pattern-matching algorithms for sparse-checkout.
>
> Signed-off-by: Jeff Hostetler <jeffhost@xxxxxxxxxxxxx>
> Signed-off-by: Derrick Stolee <dstolee@xxxxxxxxxxxxx>
> ---
> unpack-trees.c | 10 +++++++++-
> 1 file changed, 9 insertions(+), 1 deletion(-)
>
> diff --git a/unpack-trees.c b/unpack-trees.c
> index cd548f4fa2..26be8f3569 100644
> --- a/unpack-trees.c
> +++ b/unpack-trees.c
> @@ -1404,15 +1404,23 @@ static int clear_ce_flags(struct index_state *istate,
> struct pattern_list *pl)
> {
> static struct strbuf prefix = STRBUF_INIT;
> + char label[100];
> + int rval;
>
> strbuf_reset(&prefix);
>
> - return clear_ce_flags_1(istate,
> + xsnprintf(label, sizeof(label), "clear_ce_flags(0x%08lx,0x%08lx)",
> + (unsigned long)select_mask, (unsigned long)clear_mask);
> + trace2_region_enter("unpack_trees", label, the_repository);
> + rval = clear_ce_flags_1(istate,
> istate->cache,
> istate->cache_nr,
> &prefix,
> select_mask, clear_mask,
> pl, 0);
> + trace2_region_leave("unpack_trees", label, the_repository);
> +
> + return rval;
> }
>
> /*
> --
> gitgitgadget
Thanks for the updates to the commit message, and the tweaks from
"exp" to "unpack_trees" in the patch. I still don't know trace2, but
it's much clearer how this relates to the series now.
