git@vger.kernel.org list mirror (unofficial, one of many)
 help / color / mirror / code / Atom feed
From: Junio C Hamano <gitster@pobox.com>
To: Phillip Wood <phillip.wood123@gmail.com>
Cc: Srinidhi Kaushik <shrinidhi.kaushik@gmail.com>, git@vger.kernel.org
Subject: Re: [PATCH v4 1/3] push: add reflog check for "--force-if-includes"
Date: Mon, 21 Sep 2020 09:12:58 -0700	[thread overview]
Message-ID: <xmqqv9g7f6r9.fsf@gitster.c.googlers.com> (raw)
In-Reply-To: <f6bb2b1f-0f1b-f196-59f1-893580430cf2@gmail.com> (Phillip Wood's message of "Mon, 21 Sep 2020 14:19:24 +0100")

Phillip Wood <phillip.wood123@gmail.com> writes:

> As I said before[1] I think we should also be checking the reflog
> dates so that we do not look at any local reflog entries that are
> older than the most recent reflog entry for the remote tracking
> branch. This protects against a background fetch when the remote has
> been rewound and it would also reduce the number of calls to
> in_merge_bases().

Meaning we first check the timestamp of the topmost reflog entry of
remote-tracking branch (i.e. the time *we* acquired the tip commit
that we are about to lose), and leverage on the fact that no local
commit older than that timestamp can possibly be written with the
knowledge of that remote work?  Assuming that local timestamp is
monotonically increasing, it is a quite valid optimization (and the
clock skew we often talk about in the context of revision traversal
are often discrepancy between matchines).

Having said that.

The new generation number based on (adjusted) timestamp is being
worked in, and that work is supposed to bring such an optimization
to us automatically (at least on the reachability's side, i.e. logic
that uses get_merge_bases()), I think, so we probably do *not* want
to add such a heuristics specifically for this codepath.

Thanks.

  reply	other threads:[~2020-09-21 16:13 UTC|newest]

Thread overview: 120+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-09-04 18:51 [PATCH] push: make `--force-with-lease[=<ref>]` safer Srinidhi Kaushik
2020-09-07 15:23 ` Phillip Wood
2020-09-08 15:48   ` Srinidhi Kaushik
2020-09-07 16:14 ` Junio C Hamano
2020-09-08 16:00   ` Srinidhi Kaushik
2020-09-08 21:00     ` Junio C Hamano
2020-09-07 19:45 ` Johannes Schindelin
2020-09-08 15:58   ` Junio C Hamano
2020-09-09  3:40     ` Johannes Schindelin
2020-09-08 16:59   ` Srinidhi Kaushik
2020-09-16 11:55     ` Johannes Schindelin
2020-09-08 19:34   ` Junio C Hamano
2020-09-09  3:44     ` Johannes Schindelin
2020-09-10 10:22       ` Johannes Schindelin
2020-09-10 14:44         ` Srinidhi Kaushik
2020-09-11 22:16           ` Johannes Schindelin
2020-09-14 11:06             ` Srinidhi Kaushik
2020-09-14 20:08             ` Junio C Hamano
2020-09-16  5:31               ` Srinidhi Kaushik
2020-09-16 10:20                 ` Johannes Schindelin
2020-09-19 17:48                   ` Junio C Hamano
2020-09-10 14:46         ` Junio C Hamano
2020-09-11 22:17           ` Johannes Schindelin
2020-09-14 20:07             ` Junio C Hamano
2020-09-12 15:04 ` [PATCH v2 0/2] push: make "--force-with-lease" safer Srinidhi Kaushik
2020-09-12 15:04   ` [PATCH v2 1/2] push: add "--[no-]force-if-includes" Srinidhi Kaushik
2020-09-12 18:20     ` Junio C Hamano
2020-09-12 21:25       ` Srinidhi Kaushik
2020-09-12 15:04   ` [PATCH v2 2/2] push: enable "forceIfIncludesWithLease" by default Srinidhi Kaushik
2020-09-12 18:22     ` Junio C Hamano
2020-09-12 18:15   ` [PATCH v2 0/2] push: make "--force-with-lease" safer Junio C Hamano
2020-09-12 21:03     ` Srinidhi Kaushik
2020-09-13 14:54   ` [PATCH v3 0/7] push: add "--[no-]force-if-includes" Srinidhi Kaushik
2020-09-13 14:54     ` [PATCH v3 1/7] remote: add reflog check for "force-if-includes" Srinidhi Kaushik
2020-09-14 20:17       ` Junio C Hamano
2020-09-16 10:51         ` Srinidhi Kaushik
2020-09-14 20:31       ` Junio C Hamano
2020-09-14 21:13       ` Junio C Hamano
2020-09-16 12:35       ` Johannes Schindelin
2020-09-19 17:01         ` Srinidhi Kaushik
2020-09-13 14:54     ` [PATCH v3 2/7] transport: add flag for "--[no-]force-if-includes" Srinidhi Kaushik
2020-09-13 14:54     ` [PATCH v3 3/7] send-pack: check ref status for "force-if-includes" Srinidhi Kaushik
2020-09-13 14:54     ` [PATCH v3 4/7] transport-helper: update " Srinidhi Kaushik
2020-09-13 14:54     ` [PATCH v3 5/7] builtin/push: add option "--[no-]force-if-includes" Srinidhi Kaushik
2020-09-16 12:36       ` Johannes Schindelin
2020-09-13 14:54     ` [PATCH v3 6/7] doc: add reference for "--[no-]force-if-includes" Srinidhi Kaushik
2020-09-14 21:01       ` Junio C Hamano
2020-09-16  5:35         ` Srinidhi Kaushik
2020-09-13 14:54     ` [PATCH v3 7/7] t: add tests for "force-if-includes" Srinidhi Kaushik
2020-09-16 12:47     ` [PATCH v3 0/7] push: add "--[no-]force-if-includes" Johannes Schindelin
2020-09-19 17:03   ` [PATCH v4 0/3] " Srinidhi Kaushik
2020-09-19 17:03     ` [PATCH v4 1/3] push: add reflog check for "--force-if-includes" Srinidhi Kaushik
2020-09-19 20:03       ` Junio C Hamano
2020-09-21  8:42         ` Srinidhi Kaushik
2020-09-21 18:48           ` Junio C Hamano
2020-09-23 10:22             ` Srinidhi Kaushik
2020-09-23 16:47               ` Junio C Hamano
2020-09-21 13:19         ` Phillip Wood
2020-09-21 16:12           ` Junio C Hamano [this message]
2020-09-21 18:11             ` Junio C Hamano
2020-09-23 10:27           ` Srinidhi Kaushik
2020-09-19 17:03     ` [PATCH v4 2/3] push: parse and set flag " Srinidhi Kaushik
2020-09-19 20:26       ` Junio C Hamano
2020-09-19 17:03     ` [PATCH v4 3/3] t, doc: update tests, reference " Srinidhi Kaushik
2020-09-19 20:42       ` Junio C Hamano
2020-09-23  7:30     ` [PATCH v5 0/3] push: add "--[no-]force-if-includes" Srinidhi Kaushik
2020-09-23  7:30       ` [PATCH v5 1/3] push: add reflog check for "--force-if-includes" Srinidhi Kaushik
2020-09-23 10:18         ` Phillip Wood
2020-09-23 11:26           ` Srinidhi Kaushik
2020-09-23 16:24           ` Junio C Hamano
2020-09-23 16:29         ` Junio C Hamano
2020-09-23  7:30       ` [PATCH v5 2/3] push: parse and set flag " Srinidhi Kaushik
2020-09-23  7:30       ` [PATCH v5 3/3] t, doc: update tests, reference " Srinidhi Kaushik
2020-09-23 10:24         ` Phillip Wood
2020-09-26 10:13       ` [PATCH v6 0/3] push: add "--[no-]force-if-includes" Srinidhi Kaushik
2020-09-26 10:13         ` [PATCH v6 1/3] push: add reflog check for "--force-if-includes" Srinidhi Kaushik
2020-09-26 10:13         ` [PATCH v6 2/3] push: parse and set flag " Srinidhi Kaushik
2020-09-26 10:13         ` [PATCH v6 3/3] t, doc: update tests, reference " Srinidhi Kaushik
2020-09-26 10:21         ` [PATCH v6 0/3] push: add "--[no-]force-if-includes" Srinidhi Kaushik
2020-09-26 11:46         ` [PATCH v7 " Srinidhi Kaushik
2020-09-26 11:46           ` [PATCH v7 1/3] push: add reflog check for "--force-if-includes" Srinidhi Kaushik
2020-09-26 23:42             ` Junio C Hamano
2020-09-27 12:27               ` Srinidhi Kaushik
2020-09-26 11:46           ` [PATCH v7 2/3] push: parse and set flag " Srinidhi Kaushik
2020-09-26 11:46           ` [PATCH v7 3/3] t, doc: update tests, reference " Srinidhi Kaushik
2020-09-27 14:17           ` [PATCH v8 0/3] push: add "--[no-]force-if-includes" Srinidhi Kaushik
2020-09-27 14:17             ` [PATCH v8 1/3] push: add reflog check for "--force-if-includes" Srinidhi Kaushik
2020-09-27 14:17             ` [PATCH v8 2/3] push: parse and set flag " Srinidhi Kaushik
2020-09-27 14:17             ` [PATCH v8 3/3] t, doc: update tests, reference " Srinidhi Kaushik
2020-09-30 12:54               ` Philip Oakley
2020-09-30 14:27                 ` Srinidhi Kaushik
2020-09-28 17:31             ` [PATCH v8 0/3] push: add "--[no-]force-if-includes" Junio C Hamano
2020-09-28 17:46               ` SZEDER Gábor
2020-09-28 19:34                 ` Srinidhi Kaushik
2020-09-28 19:51                   ` Junio C Hamano
2020-09-28 20:00                 ` Junio C Hamano
2020-10-01  8:21             ` [PATCH v9 " Srinidhi Kaushik
2020-10-01  8:21               ` [PATCH v9 1/3] push: add reflog check for "--force-if-includes" Srinidhi Kaushik
2020-10-02 13:52                 ` Johannes Schindelin
2020-10-02 14:50                   ` Johannes Schindelin
2020-10-02 16:22                     ` Junio C Hamano
2020-10-02 15:07                   ` Srinidhi Kaushik
2020-10-02 16:41                     ` Junio C Hamano
2020-10-02 19:39                       ` Srinidhi Kaushik
2020-10-02 20:14                         ` Junio C Hamano
2020-10-02 20:58                           ` Srinidhi Kaushik
2020-10-02 21:36                             ` Junio C Hamano
2020-10-02 16:26                   ` Junio C Hamano
2020-10-01  8:21               ` [PATCH v9 2/3] push: parse and set flag " Srinidhi Kaushik
2020-10-01  8:21               ` [PATCH v9 3/3] t, doc: update tests, reference " Srinidhi Kaushik
2020-10-01 15:46               ` [PATCH v9 0/3] push: add "--[no-]force-if-includes" Junio C Hamano
2020-10-01 17:12                 ` Junio C Hamano
2020-10-01 17:54                   ` Srinidhi Kaushik
2020-10-01 18:32                     ` Junio C Hamano
2020-10-02 16:50                     ` Junio C Hamano
2020-10-02 19:42                       ` Srinidhi Kaushik
2020-10-03 12:10               ` [PATCH v10 " Srinidhi Kaushik
2020-10-03 12:10                 ` [PATCH v10 1/3] push: add reflog check for "--force-if-includes" Srinidhi Kaushik
2020-10-03 12:10                 ` [PATCH v10 2/3] push: parse and set flag " Srinidhi Kaushik
2020-10-03 12:10                 ` [PATCH v10 3/3] t, doc: update tests, reference " Srinidhi Kaushik

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

  List information: http://vger.kernel.org/majordomo-info.html

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=xmqqv9g7f6r9.fsf@gitster.c.googlers.com \
    --to=gitster@pobox.com \
    --cc=git@vger.kernel.org \
    --cc=phillip.wood123@gmail.com \
    --cc=shrinidhi.kaushik@gmail.com \
    --subject='Re: [PATCH v4 1/3] push: add reflog check for "--force-if-includes"' \
    /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

Code repositories for project(s) associated with this inbox:

	https://80x24.org/mirrors/git.git

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).