Re: [controller-dev] [documentation] Questions about ODL clustering

2016-09-14 Thread Muthukumaran K 
Hi Srini,

We have tried the approach what Moiz had mentioned – using CDTCN and caching 
data, and it was quite performant in one of our reference application. You may 
want to look - https://git.opendaylight.org/gerrit/#/c/45131/

Regards
Muthu



From: controller-dev-boun...@lists.opendaylight.org 
[mailto:controller-dev-boun...@lists.opendaylight.org] On Behalf Of Moiz Raja 
(moraja)
Sent: Thursday, September 15, 2016 3:06 AM
To: Tom Pantelis; Srini Seetharaman
Cc: controller-dev
Subject: Re: [controller-dev] [documentation] Questions about ODL clustering

The single use ClusteredDataChange/ClusteredDataTreeChange listeners are fine 
and may perform better than the remote read but if you really have a lot of 
reads even this mechanism is expensive as there is quite a bit of overhead 
associated with setting up a listener.

I would recommend that you setup a ClusteredDataTreeChangeListener (for long 
term use) for the data that you want to constantly read and cache the data in 
that listener. Then provide a way to read from that cache.

-Moiz

From: Tom Pantelis >
Date: Wednesday, September 14, 2016 at 2:26 PM
To: Srini Seetharaman 
>
Cc: Moiz Raja >, controller-dev 
>
Subject: Re: [controller-dev] [documentation] Questions about ODL clustering

All reads still go to the leader.  There has been an enhancement 
https://bugs.opendaylight.org/show_bug.cgi?id=2504 open for this but hasn't 
been implemented. There is an alternative way using a DataTreeChangeListener as 
Moiz mentioned in the bug.

On Wed, Sep 14, 2016 at 4:57 PM, Srini Seetharaman 
> wrote:
With Beryllium-SR3, I just verified using tcpdump on port 2550 that the data 
for the read operation at the follower came over the network from the shard 
leader.

Is there any plan with Boron to make it a local read from the replica?

On Wed, Sep 14, 2016 at 1:43 PM, Srini Seetharaman 
> wrote:
Hi Tom and Moiz
Is it still the case with Beryllium and Boron that the read transactions from a 
follower are forwarded to the leader?

Thanks
Srini.

On Sat, Feb 28, 2015 at 8:26 AM, Tom Pantelis 
> wrote:
Colin, Tianzhu

Reads are also forwarded to the leader so, yes, remote reads would take longer. 
With IMDS, reads are actually synchronous so the returned Future is immediate 
but with CDS, the read is async, whether it's local or not. So it's best to not 
block on the Future as there will be some latency with CDS, but rather use a 
Future callback if possible.

Tom

On Sat, Feb 28, 2015 at 10:42 AM, Colin Dixon 
> wrote:
I'm cc'ing controller-dev since they will have the authoritative answer.
I *think* the answer is that all data is replicated to all nodes in the cluster 
and so all reads can be local. Only writes have to go to the shard leader, but 
I could be wrong.
Moiz and Tom Pantelis would know more.

--Colin

On Sat, Feb 28, 2015 at 4:55 AM, 我心永恒 
> wrote:
Dear all, I am studying ODL and have one question:

When a consumer launches a read transaction, if I'm not wrong, it has to be 
forwarded to the primary shard controller. So if this case is possible that the 
transaction is remote and the consumer has to wait longer since the transaction 
is not local?

  Thanks & regards
  Tianzhu


___
documentation mailing list
documentat...@lists.opendaylight.org
https://lists.opendaylight.org/mailman/listinfo/documentation


___
controller-dev mailing list
controller-dev@lists.opendaylight.org
https://lists.opendaylight.org/mailman/listinfo/controller-dev


___
controller-dev mailing list
controller-dev@lists.opendaylight.org
https://lists.opendaylight.org/mailman/listinfo/controller-dev



___
controller-dev mailing list
controller-dev@lists.opendaylight.org
https://lists.opendaylight.org/mailman/listinfo/controller-dev

Re: [controller-dev] [documentation] Questions about ODL clustering

2016-09-14 Thread Moiz Raja (moraja) 
The single use ClusteredDataChange/ClusteredDataTreeChange listeners are fine 
and may perform better than the remote read but if you really have a lot of 
reads even this mechanism is expensive as there is quite a bit of overhead 
associated with setting up a listener.

I would recommend that you setup a ClusteredDataTreeChangeListener (for long 
term use) for the data that you want to constantly read and cache the data in 
that listener. Then provide a way to read from that cache.

-Moiz

From: Tom Pantelis >
Date: Wednesday, September 14, 2016 at 2:26 PM
To: Srini Seetharaman 
>
Cc: Moiz Raja >, controller-dev 
>
Subject: Re: [controller-dev] [documentation] Questions about ODL clustering

All reads still go to the leader.  There has been an enhancement 
https://bugs.opendaylight.org/show_bug.cgi?id=2504 open for this but hasn't 
been implemented. There is an alternative way using a DataTreeChangeListener as 
Moiz mentioned in the bug.

On Wed, Sep 14, 2016 at 4:57 PM, Srini Seetharaman 
> wrote:
With Beryllium-SR3, I just verified using tcpdump on port 2550 that the data 
for the read operation at the follower came over the network from the shard 
leader.

Is there any plan with Boron to make it a local read from the replica?

On Wed, Sep 14, 2016 at 1:43 PM, Srini Seetharaman 
> wrote:
Hi Tom and Moiz
Is it still the case with Beryllium and Boron that the read transactions from a 
follower are forwarded to the leader?

Thanks
Srini.

On Sat, Feb 28, 2015 at 8:26 AM, Tom Pantelis 
> wrote:
Colin, Tianzhu

Reads are also forwarded to the leader so, yes, remote reads would take longer. 
With IMDS, reads are actually synchronous so the returned Future is immediate 
but with CDS, the read is async, whether it's local or not. So it's best to not 
block on the Future as there will be some latency with CDS, but rather use a 
Future callback if possible.

Tom

On Sat, Feb 28, 2015 at 10:42 AM, Colin Dixon 
> wrote:
I'm cc'ing controller-dev since they will have the authoritative answer.

I *think* the answer is that all data is replicated to all nodes in the cluster 
and so all reads can be local. Only writes have to go to the shard leader, but 
I could be wrong.

Moiz and Tom Pantelis would know more.

--Colin


On Sat, Feb 28, 2015 at 4:55 AM, 我心永恒 
> wrote:
Dear all, I am studying ODL and have one question:

When a consumer launches a read transaction, if I'm not wrong, it has to be 
forwarded to the primary shard controller. So if this case is possible that the 
transaction is remote and the consumer has to wait longer since the transaction 
is not local?

  Thanks & regards
  Tianzhu


___
documentation mailing list
documentat...@lists.opendaylight.org
https://lists.opendaylight.org/mailman/listinfo/documentation



___
controller-dev mailing list
controller-dev@lists.opendaylight.org
https://lists.opendaylight.org/mailman/listinfo/controller-dev



___
controller-dev mailing list
controller-dev@lists.opendaylight.org
https://lists.opendaylight.org/mailman/listinfo/controller-dev




___
controller-dev mailing list
controller-dev@lists.opendaylight.org
https://lists.opendaylight.org/mailman/listinfo/controller-dev