Is is possible that user data sending will block heartbeat package

[赵琦]

Hi Bela,

Is is possible that user data sending will block heartbeat package. When I test jgroups-raft on 4 node cluster, I find that some times heartbeat will delay and cause election timeout.

Thanks,

Qi

[Bela Ban]

Are you referring to FD_ALL? A heartbeat sent by this protocol should
never block anything...

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[赵琦]

Hi Bela,

I means the Heartbeat of raft protocol. I observed that the heartbeat of raft protocol some times was not send to follower in time an case election.

Thanks,

Qi 

在 2017年4月13日星期四 UTC+8下午3:21:08，Bela Ban写道：

Are you referring to FD_ALL? A heartbeat sent by this protocol should
never block anything...

On 13/04/17 03:26, 赵琦 wrote:
> Hi Bela,
>
> Is is possible that user data sending will block heartbeat package. When
> I test jgroups-raft on 4 node cluster, I find that some times heartbeat
> will delay and cause election timeout.
>
> Thanks,
> Qi
>
> --
> You received this message because you are subscribed to the Google
> Groups "jgroups-raft" group.
> To unsubscribe from this group and stop receiving emails from it, send
> an email to jgroups-raft...@googlegroups.com

> <mailto:jgroups-raft+unsub...@googlegroups.com>.

[Bela Ban]

You need to be a bit more specific, what exactly happened and what
symptoms did it cause?

The leader sends a periodic heartbeat to prevent followers from trying
to become leaders.

These heartbeat messages are sent _unreliably_, ie. they may get dropped
and there is no retransmission performed by JGroups.

In case a follower doesn't receive a couple of heartbeats, it may select
to become leader by starting an election. However, to actually become
leader, it requires a majority of votes, and that's unlikely unless a
majority of members didn't receive their heartbeats, either.

In the unlikely case the new would-be leader does indeed get a majority
of votes (and has the longest log), it would become the new leader, but
this is fine, and entirely within the scope of the Raft protocol.

On 14/04/17 14:10, 赵琦 wrote:
> Hi Bela,
>
> I means the Heartbeat of raft protocol. I observed that the heartbeat of
> raft protocol some times was not send to follower in time an case election.
>
> Thanks,
> Qi
>
> 在 2017年4月13日星期四 UTC+8下午3:21:08，Bela Ban写道：
>
> Are you referring to FD_ALL? A heartbeat sent by this protocol should
> never block anything...
>
> On 13/04/17 03:26, 赵琦 wrote:
> > Hi Bela,
> >
> > Is is possible that user data sending will block heartbeat
> package. When
> > I test jgroups-raft on 4 node cluster, I find that some times
> heartbeat
> > will delay and cause election timeout.
> >
> > Thanks,
> > Qi
> >
> > --
> > You received this message because you are subscribed to the Google
> > Groups "jgroups-raft" group.
> > To unsubscribe from this group and stop receiving emails from it,
> send

> > an email to jgroups-raft...@googlegroups.com <javascript:>
> > <mailto:jgroups-raft...@googlegroups.com <javascript:>>.

> > To post to this group, send email to jgroup...@googlegroups.com

> <javascript:>
> > <mailto:jgroup...@googlegroups.com <javascript:>>.

> > To view this discussion on the web visit
> >
> https://groups.google.com/d/msgid/jgroups-raft/dbe18210-582e-4995-ad10-22414e023ee3%40googlegroups.com
> <https://groups.google.com/d/msgid/jgroups-raft/dbe18210-582e-4995-ad10-22414e023ee3%40googlegroups.com>
>
> >

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>
> > For more options, visit https://groups.google.com/d/optout

> <https://groups.google.com/d/optout>.