Tarantool development patches archive
 help / color / mirror / Atom feed
From: Cyrill Gorcunov via Tarantool-patches <tarantool-patches@dev.tarantool.org>
To: Vladislav Shpilevoy <v.shpilevoy@tarantool.org>
Cc: tml <tarantool-patches@dev.tarantool.org>
Subject: Re: [Tarantool-patches] [PATCH v8 0/2] relay: provide downstream lag information
Date: Mon, 7 Jun 2021 23:00:29 +0300
Message-ID: <YL563WfTfvQKMSwl@grain> (raw)
In-Reply-To: <fdaaf89e-1bfd-dc01-d719-d274292f2486@tarantool.org>

On Mon, Jun 07, 2021 at 09:20:50PM +0200, Vladislav Shpilevoy wrote:
> Hi! Thanks for the patchset!
> 
> Please, provide branch and issue links next time.
> https://github.com/tarantool/tarantool/wiki/Code-review-procedure#sending-the-patch
> 
> I assume your branch is gorcunov/gh-5447-relay-lag-8.

It was there, letme quote it for you, I think you might simply
miss it from a glance

 > branch gorcunov/gh-5447-relay-lag-8
 > issue https://github.com/tarantool/tarantool/issues/5447


> It seems after your changes some tests start failing. Looks
> like you didn't clear artifacts of your new test.
> https://github.com/tarantool/tarantool/runs/2765786321

I'll take a look, thanks!

> On 07.06.2021 17:55, Cyrill Gorcunov wrote:
> > Guys, take a look once time permit. Previous version is here
> > 
> > https://lists.tarantool.org/tarantool-patches/20210506214132.533913-1-gorcunov@gmail.com/
> > 
> > I still think we might need some general statistics engine because this
> > lag rather common data and we could move other "last" things like last_row_time
> > there but since I didn't get approve on the idea I keep the timestamp
> > in replica structure.
> 
> If you are talking about your perf metrics engine which we tried to
> design for replication, it was approved. The problem is that there was
> no a really good design on how should it look and work.

Not perf metrics (as we were discussed time back then seems plain perf is
more than enough for most of developers if I'm not mistaken). I rather though
of my previous RFC where I proposed to have some common and shared "stat" engine
with rw operations:

 > Not for merging yet! I think instead of applier_wal_stat structure we might need some
 > _commonly shared_ statistics structure, probably bound to WAL code and all other
 > threads will update it in a lockless way, because we might need to collect more
 > detais on WAL processing in future. I though of something like
 > 
 > 	enum {
 > 		WAL_ICNT__APPLIER_TXN_START_TM,
 > 
 > 		WAL_ICNT__MAX,
 > 	};
 > 
 > 	struct wal_stat {
 > 		int64_t	icnt[WAL_ICNT__MAX];
 > 	} wal_st[VCLOCK_MAX];
 > 
 > and introduce
 > 
 > 	wal_st__icnt_read(unsigned id);
 > 	wal_st__icnt_write(unsigned id);
 > 
 > then applier will simply push last timestamp to WAL_ICNT__APPLIER_TXN_START_TM
 > counter, and later when we need to send ACK we use wal_st__icnt_read() to
 > fetch it back. We won't need to allocate some dynamic memory for it but
 > rather use statically preallocated shared between threads.

      reply	other threads:[~2021-06-07 20:00 UTC|newest]

Thread overview: 17+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-06-07 15:55 Cyrill Gorcunov via Tarantool-patches
2021-06-07 15:55 ` [Tarantool-patches] [PATCH v8 1/2] applier: send transaction's first row WAL time in the applier_writer_f Cyrill Gorcunov via Tarantool-patches
2021-06-07 19:20   ` Vladislav Shpilevoy via Tarantool-patches
2021-06-15  9:36   ` Serge Petrenko via Tarantool-patches
2021-06-16 13:32     ` Cyrill Gorcunov via Tarantool-patches
2021-06-17  9:16       ` Serge Petrenko via Tarantool-patches
2021-06-07 15:55 ` [Tarantool-patches] [PATCH v8 2/2] relay: provide information about downstream lag Cyrill Gorcunov via Tarantool-patches
2021-06-07 19:21   ` Vladislav Shpilevoy via Tarantool-patches
2021-06-08  8:40     ` Cyrill Gorcunov via Tarantool-patches
2021-06-08  9:58       ` Cyrill Gorcunov via Tarantool-patches
2021-06-08 18:15       ` Vladislav Shpilevoy via Tarantool-patches
2021-06-15 10:03   ` Serge Petrenko via Tarantool-patches
2021-06-17  6:55     ` Cyrill Gorcunov via Tarantool-patches
2021-06-17  9:01       ` Serge Petrenko via Tarantool-patches
2021-06-17  9:58         ` Cyrill Gorcunov via Tarantool-patches
2021-06-07 19:20 ` [Tarantool-patches] [PATCH v8 0/2] relay: provide downstream lag information Vladislav Shpilevoy via Tarantool-patches
2021-06-07 20:00   ` Cyrill Gorcunov via Tarantool-patches [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=YL563WfTfvQKMSwl@grain \
    --to=tarantool-patches@dev.tarantool.org \
    --cc=gorcunov@gmail.com \
    --cc=v.shpilevoy@tarantool.org \
    /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

Tarantool development patches archive

This inbox may be cloned and mirrored by anyone:

	git clone --mirror https://lists.tarantool.org/tarantool-patches/0 tarantool-patches/git/0.git

	# If you have public-inbox 1.1+ installed, you may
	# initialize and index your mirror using the following commands:
	public-inbox-init -V2 tarantool-patches tarantool-patches/ https://lists.tarantool.org/tarantool-patches \
		tarantool-patches@dev.tarantool.org.
	public-inbox-index tarantool-patches

Example config snippet for mirrors.


AGPL code for this site: git clone https://public-inbox.org/public-inbox.git