From: Cyrill Gorcunov <gorcunov@gmail.com>
To: Vladislav Shpilevoy <v.shpilevoy@tarantool.org>
Cc: tarantool-patches@dev.tarantool.org
Subject: Re: [Tarantool-patches] [PATCH v2 1/1] memtx: force async snapshot transactions
Date: Mon, 14 Sep 2020 11:12:02 +0300 [thread overview]
Message-ID: <20200914081202.GD269870@grain> (raw)
In-Reply-To: <5a6c33ec7bfffd3d0dd201a1b38cc5205f0f0ea4.1600025872.git.v.shpilevoy@tarantool.org>
On Sun, Sep 13, 2020 at 09:39:26PM +0200, Vladislav Shpilevoy wrote:
> Snapshot rows contain not real LSNs. Instead their LSNs are
> signatures, ordinal numbers. Rows in the snap have LSNs from 1 to
> the number of rows. This is because LSNs are not stored with every
> tuple in the storages, and there is no way to store real LSNs in
> the snapshot.
>
> These artificial LSNs broke the synchronous replication limbo.
> After snap recovery is done, limbo vclock was broken - it
> contained numbers not related to reality, and affected by rows
> from local spaces.
>
> Also the recovery could stuck because ACKs in the limbo stopped
> working after a first row - the vclock was set to the final
> signature right away.
>
> This patch makes all snapshot recovered rows async. Because they
> are confirmed by definition. So now the limbo is not involved into
> the snapshot recovery.
>
> Closes #5298
Reviewed-by: Cyrill Gorcunov <gorcunov@gmail.com>
next prev parent reply other threads:[~2020-09-14 8:12 UTC|newest]
Thread overview: 4+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-09-13 19:39 Vladislav Shpilevoy
2020-09-14 8:12 ` Cyrill Gorcunov [this message]
2020-09-14 9:15 ` Serge Petrenko
2020-09-14 20:01 ` Vladislav Shpilevoy
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=20200914081202.GD269870@grain \
--to=gorcunov@gmail.com \
--cc=tarantool-patches@dev.tarantool.org \
--cc=v.shpilevoy@tarantool.org \
--subject='Re: [Tarantool-patches] [PATCH v2 1/1] memtx: force async snapshot transactions' \
/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
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox