From: Junio C Hamano <gitster@pobox.com>
To: Patrick Steinhardt <ps@pks.im>
Cc: git@vger.kernel.org
Subject: Re: [PATCH 2/2] fetch: implement support for atomic reference updates
Date: Thu, 07 Jan 2021 16:19:37 -0800 [thread overview]
Message-ID: <xmqqeeiwjn52.fsf@gitster.c.googlers.com> (raw)
In-Reply-To: <4807344e92bedbac37243434850da1f0787ad496.1610027375.git.ps@pks.im> (Patrick Steinhardt's message of "Thu, 7 Jan 2021 14:51:44 +0100")
Patrick Steinhardt <ps@pks.im> writes:
> Similar to `git push --atomic`, this commit thus introduces atomic
> fetches. Instead of allocating one reference transaction per updated
> reference, it causes us to only allocate a single transaction and commit
> it as soon as all updates were received. If locking of any reference
> fails, then we abort the complete transaction and don't update any
> reference, which gives us an all-or-nothing fetch.
>
> Note that this may not completely fix the first of above downsides, as
> the consistent view also depends on the server-side. If the server
> doesn't have a consistent view of its own references during the
> reference negotiation phase, then the client would get the same
> inconsistent view the server has. This is a separate problem though and,
> if it actually exists, can be fixed at a later point.
With the help of the previous step, it is trivial to see that the
single transaction around store_updated_refs() would be sufficient
to achieve the atomicity.
But what about FETCH_HEAD? Do we refrain from writing and/or appending
to it when there is any failure?
Thanks.
next prev parent reply other threads:[~2021-01-08 0:21 UTC|newest]
Thread overview: 41+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-01-07 13:51 [PATCH 0/2] fetch: implement support for atomic reference updates Patrick Steinhardt
2021-01-07 13:51 ` [PATCH 1/2] fetch: allow passing a transaction to `s_update_ref()` Patrick Steinhardt
2021-01-07 22:59 ` Junio C Hamano
2021-01-08 0:45 ` Christian Couder
2021-01-08 7:18 ` Junio C Hamano
2021-01-07 13:51 ` [PATCH 2/2] fetch: implement support for atomic reference updates Patrick Steinhardt
2021-01-08 0:19 ` Junio C Hamano [this message]
2021-01-08 12:11 ` [PATCH v2 0/4] " Patrick Steinhardt
2021-01-08 12:11 ` [PATCH v2 1/4] fetch: extract writing to FETCH_HEAD Patrick Steinhardt
2021-01-08 23:40 ` Junio C Hamano
2021-01-11 10:26 ` Patrick Steinhardt
2021-01-11 19:24 ` Junio C Hamano
2021-01-08 12:11 ` [PATCH v2 2/4] fetch: refactor `s_update_ref` to use common exit path Patrick Steinhardt
2021-01-08 23:50 ` Junio C Hamano
2021-01-11 10:28 ` Patrick Steinhardt
2021-01-08 12:11 ` [PATCH v2 3/4] fetch: allow passing a transaction to `s_update_ref()` Patrick Steinhardt
2021-01-08 23:53 ` Junio C Hamano
2021-01-08 12:11 ` [PATCH v2 4/4] fetch: implement support for atomic reference updates Patrick Steinhardt
2021-01-09 0:05 ` Junio C Hamano
2021-01-11 10:42 ` Patrick Steinhardt
2021-01-11 19:47 ` Junio C Hamano
2021-01-12 12:22 ` Patrick Steinhardt
2021-01-12 12:29 ` Patrick Steinhardt
2021-01-12 19:19 ` Junio C Hamano
2021-01-11 11:05 ` [PATCH v3 0/5] " Patrick Steinhardt
2021-01-11 11:05 ` [PATCH v3 1/5] fetch: extract writing to FETCH_HEAD Patrick Steinhardt
2021-01-11 23:16 ` Junio C Hamano
2021-01-11 11:05 ` [PATCH v3 2/5] fetch: use strbuf to format FETCH_HEAD updates Patrick Steinhardt
2021-01-11 11:10 ` Patrick Steinhardt
2021-01-11 11:17 ` Christian Couder
2021-01-11 23:21 ` Junio C Hamano
2021-01-11 11:05 ` [PATCH v3 3/5] fetch: refactor `s_update_ref` to use common exit path Patrick Steinhardt
2021-01-11 11:05 ` [PATCH v3 4/5] fetch: allow passing a transaction to `s_update_ref()` Patrick Steinhardt
2021-01-11 11:05 ` [PATCH v3 5/5] fetch: implement support for atomic reference updates Patrick Steinhardt
2021-01-12 0:04 ` [PATCH v3 0/5] " Junio C Hamano
2021-01-12 12:27 ` [PATCH v4 " Patrick Steinhardt
2021-01-12 12:27 ` [PATCH v4 1/5] fetch: extract writing to FETCH_HEAD Patrick Steinhardt
2021-01-12 12:27 ` [PATCH v4 2/5] fetch: use strbuf to format FETCH_HEAD updates Patrick Steinhardt
2021-01-12 12:27 ` [PATCH v4 3/5] fetch: refactor `s_update_ref` to use common exit path Patrick Steinhardt
2021-01-12 12:27 ` [PATCH v4 4/5] fetch: allow passing a transaction to `s_update_ref()` Patrick Steinhardt
2021-01-12 12:27 ` [PATCH v4 5/5] fetch: implement support for atomic reference updates Patrick Steinhardt
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