Tarantool development patches archive
 help / color / mirror / Atom feed
From: Konstantin Osipov <kostja.osipov@gmail.com>
To: Serge Petrenko <sergepetrenko@tarantool.org>
Cc: tarantool-patches@dev.tarantool.org, v.shpilevoy@tarantool.org
Subject: Re: [Tarantool-patches] [PATCH v4 4/4] box: start counting local space requests separately
Date: Sat, 28 Mar 2020 19:23:28 +0300	[thread overview]
Message-ID: <20200328162328.GC20621@atlas> (raw)
In-Reply-To: <b8c746f9595ca0d8141df7cd0d27102406ac258e.1585303629.git.sergepetrenko@tarantool.org>

* Serge Petrenko <sergepetrenko@tarantool.org> [20/03/27 18:08]:
> Moreover, it fixes the following bug with local spaces and replication.
> In a situation when there are a master and a replica set up, replica may
> still write to local spaces even if it's read-only. Local space
> operations used to promote instance's lsn before this patch. Eventually,
> master would have vclock {1:x} and replica'd have vclock {1:x, 2:y},
> where y > 0, due to local space requests performed by the replica.
> If a snapshot happens on replica side, replica will delete it's .xlog
> files prior to the snapshot, since no one replicates from it and thus it
> doesn't have any registered GC consumers.
> From this point, every attempt to configure replication from replica to
> master will fail, since master will try to fetch records which account
> for the difference in master's and replica's vclocks: {1:x} vs {1:x,2:y},
> even though master will never need the rows in range {2:1} - {2:y},
> since they'll be turned to NOPs during replication.

OK, got it.

Makes sense.

Then, I'm afraid, relay has to be using lexicographical vclock as
well.

Waiting a fix or clarification here.


-- 
Konstantin Osipov, Moscow, Russia

      parent reply	other threads:[~2020-03-28 16:23 UTC|newest]

Thread overview: 14+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-03-27 10:20 [Tarantool-patches] [PATCH v4 0/4] replication: fix local space tracking Serge Petrenko
2020-03-27 10:20 ` [Tarantool-patches] [PATCH v4 1/4] vclock: add an ability to reset individual clock components Serge Petrenko
2020-03-27 10:20 ` [Tarantool-patches] [PATCH v4 2/4] replication: hide 0-th vclock components in replication responses Serge Petrenko
2020-03-28  5:57   ` Konstantin Osipov
2020-03-30 11:02     ` Serge Petrenko
2020-03-30 12:52       ` Konstantin Osipov
2020-03-27 10:20 ` [Tarantool-patches] [PATCH v4 3/4] gc: rely on minimal vclock components instead of signatures Serge Petrenko
2020-03-28  6:03   ` Konstantin Osipov
2020-03-30 11:02     ` Serge Petrenko
2020-03-30 12:54       ` Konstantin Osipov
2020-03-27 10:20 ` [Tarantool-patches] [PATCH v4 4/4] box: start counting local space requests separately Serge Petrenko
2020-03-28  6:17   ` Konstantin Osipov
2020-03-30 11:02     ` Serge Petrenko
2020-03-28 16:23   ` Konstantin Osipov [this message]

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=20200328162328.GC20621@atlas \
    --to=kostja.osipov@gmail.com \
    --cc=sergepetrenko@tarantool.org \
    --cc=tarantool-patches@dev.tarantool.org \
    --cc=v.shpilevoy@tarantool.org \
    --subject='Re: [Tarantool-patches] [PATCH v4 4/4] box: start counting local space requests separately' \
    /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