From: Junio C Hamano <gitster@pobox.com>
To: "Anh Le via GitGitGadget" <gitgitgadget@gmail.com>
Cc: git@vger.kernel.org, Timothy Jones <timothy@canva.com>,
Jeff Hostetler <jeffhost@microsoft.com>, Anh Le <anh@canva.com>
Subject: Re: [PATCH] index: add trace2 region for clear skip worktree
Date: Tue, 25 Oct 2022 20:16:45 -0700 [thread overview]
Message-ID: <xmqq35bbmfz6.fsf@gitster.g> (raw)
In-Reply-To: pull.1368.git.git.1666742722502.gitgitgadget@gmail.com
"Anh Le via GitGitGadget" <gitgitgadget@gmail.com> writes:
> From: Anh Le <anh@canva.com>
>
> In a large repository using sparse checkout, checking
> whether a file marked with skip worktree is present
> on disk and its skip worktree bit should be cleared
> can take a considerable amount of time. Add a trace2
> region to surface this information.
>
> Signed-off-by: Anh Le <anh@canva.com>
> ---
> index: add trace2 region for clear skip worktree
>
> In large repository using sparse checkout, checking whether a file
> marked with skip worktree is present on disk and its skip worktree bit
> should be cleared can take a considerable amount of time. Add a trace2
> region to surface this information.
It is easy to see that the change is no-op from functionality's
standpoint. The condition under which ce->ce_flags loses the
CE_SKIP_WORKTREE bit is the same as before, and the only change is
that in the iteration a couple of variables are incremented, which
may (or may not) have performance impact, but shouldn't break
correctness.
I am not sure about the value of these counters, honestly.
If we hit a sparse dir just once, we fully flatten the index and go
back to the restart state, and it would be a bug if we still see a
sparsified directory in the in-core index after that point, so
restart_count would be at most one, wouldn't it? Why do we even
need to count with intmax_t?
Similarly, path_count is bounded by istate->cache_nr. As you know
the approximate size of your project, I am not sure what extra
information you want to get by counting the paths with the skip bit
set before the first sparsified directory in the in-core index
twice, and the other paths with the skip bit set just once, and
adding these numbers together. Also again, I am not quite sure what
the point is to count the paths in intmax_t.
> Published-As: https://github.com/gitgitgadget/git/releases/tag/pr-git-1368%2FHaizzz%2Fmaster-v1
> Fetch-It-Via: git fetch https://github.com/gitgitgadget/git pr-git-1368/Haizzz/master-v1
> Pull-Request: https://github.com/git/git/pull/1368
>
> sparse-index.c | 21 +++++++++++++++------
> 1 file changed, 15 insertions(+), 6 deletions(-)
>
> diff --git a/sparse-index.c b/sparse-index.c
> index e4a54ce1943..d11049c8aeb 100644
> --- a/sparse-index.c
> +++ b/sparse-index.c
> @@ -493,24 +493,33 @@ void clear_skip_worktree_from_present_files(struct index_state *istate)
> int dir_found = 1;
>
> int i;
> + intmax_t path_count = 0;
> + intmax_t restart_count = 0;
>
> if (!core_apply_sparse_checkout ||
> sparse_expect_files_outside_of_patterns)
> return;
>
> + trace2_region_enter("index", "clear_skip_worktree_from_present_files", istate->repo);
> restart:
> for (i = 0; i < istate->cache_nr; i++) {
> struct cache_entry *ce = istate->cache[i];
>
> - if (ce_skip_worktree(ce) &&
> - path_found(ce->name, &last_dirname, &dir_len, &dir_found)) {
> - if (S_ISSPARSEDIR(ce->ce_mode)) {
> - ensure_full_index(istate);
> - goto restart;
> + if (ce_skip_worktree(ce)) {
> + path_count++;
> + if (path_found(ce->name, &last_dirname, &dir_len, &dir_found)) {
> + if (S_ISSPARSEDIR(ce->ce_mode)) {
> + ensure_full_index(istate);
> + restart_count++;
> + goto restart;
> + }
> + ce->ce_flags &= ~CE_SKIP_WORKTREE;
> }
> - ce->ce_flags &= ~CE_SKIP_WORKTREE;
> }
> }
> + trace2_data_intmax("index", istate->repo, "clear_skip_worktree_from_present_files/path_count", path_count);
> + trace2_data_intmax("index", istate->repo, "clear_skip_worktree_from_present_files/restart_count", restart_count);
> + trace2_region_leave("index", "clear_skip_worktree_from_present_files", istate->repo);
> }
>
> /*
>
> base-commit: 1fc3c0ad407008c2f71dd9ae1241d8b75f8ef886
next prev parent reply other threads:[~2022-10-26 3:16 UTC|newest]
Thread overview: 18+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-10-26 0:05 [PATCH] index: add trace2 region for clear skip worktree Anh Le via GitGitGadget
2022-10-26 3:16 ` Junio C Hamano [this message]
2022-10-26 14:13 ` Jeff Hostetler
2022-10-26 16:01 ` Junio C Hamano
2022-10-26 18:29 ` Jeff Hostetler
2022-10-27 0:04 ` Anh Le
2022-10-28 0:46 ` [PATCH v2] " Anh Le via GitGitGadget
2022-10-28 15:49 ` Derrick Stolee
2022-10-28 17:17 ` Junio C Hamano
2022-10-30 23:28 ` Anh Le
2022-10-28 16:50 ` Jeff Hostetler
2022-10-31 0:56 ` [PATCH v3] " Anh Le via GitGitGadget
2022-10-31 22:34 ` Taylor Blau
2022-11-03 23:04 ` [PATCH v4 0/2] " Anh Le via GitGitGadget
2022-11-03 23:05 ` [PATCH v4 1/2] " Anh Le via GitGitGadget
2022-11-03 23:05 ` [PATCH v4 2/2] index: raise a bug if the index is materialised more than once Anh Le via GitGitGadget
2022-11-05 0:29 ` [PATCH v4 0/2] index: add trace2 region for clear skip worktree Taylor Blau
2022-11-07 20:50 ` Derrick Stolee
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=xmqq35bbmfz6.fsf@gitster.g \
--to=gitster@pobox.com \
--cc=anh@canva.com \
--cc=git@vger.kernel.org \
--cc=gitgitgadget@gmail.com \
--cc=jeffhost@microsoft.com \
--cc=timothy@canva.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for read-only IMAP folder(s) and NNTP newsgroup(s).