Thanks for explaining.  Your explanation for filtered replications was my 
guess, but I thought I would mention it anyway.

-- Andreas


________________________________
 From: Filipe David Manana <[email protected]>
To: [email protected]; Andreas Kemkes <[email protected]> 
Sent: Thursday, June 21, 2012 12:40 PM
Subject: Re: Replication and checkpoints - what to expect?
 
On Thu, Jun 21, 2012 at 8:28 PM, Andreas Kemkes <[email protected]> wrote:
> The bump was by mistake, I wanted to add to it (i.e., stalling replication - 
> see other reply).  Thanks for answering.
>
> It should report 100% in my opinion if it has caught up with the current 
> source sequence, even though in the future there might be more.

That is the case for continuous replications. When target has caught
up with the source, it goes to 100%. When source gets new stuff,
target will report a progress < 100% for some time, and then
eventually back to 100%.

>
> The same should be true for filtered replications if there is no applicable 
> document between the current source sequence and the last checkpoint.  
> Otherwise you would be always wondering if it has been replicated entirely.

That's harder. With filtered replication, we only know about sequence
numbers of changes that pass the filter.

>
> -- Andreas
>
>
> ________________________________
>  From: Robert Newson <[email protected]>
> To: [email protected]; Andreas Kemkes <[email protected]>
> Sent: Thursday, June 21, 2012 10:40 AM
> Subject: Re: Replication and checkpoints - what to expect?
>
>
> If you're running continuous replication, then the process isn't going to 
> reach 100% (since that would imply all future changes have been replicated, 
> which is clearly impossible). I suspect it's just a reporting anomaly. I 
> didn't reply earlier because I hadn't had time to verify the code but since 
> you bumped the thread, I thought I'd best say something.
>
> B.
>
>
> On 21 Jun 2012, at 17:50, Andreas Kemkes wrote:
>
>> Reply to [email protected]
>>
>>
>> ________________________________
>> From: Andreas Kemkes <[email protected]>
>> To: "[email protected]" <[email protected]>
>> Sent: Tuesday, June 19, 2012 5:36 PM
>> Subject: Replication and checkpoints - what to expect?
>>
>> Upgrading to 1.2 on the target system allowed me to setup an unfiltered 
>> continuous replication between a couchdb 1.1.1 instance and a couchdb 1.2 
>> and then use the latter as the source for several filtered continuous 
>> replications to shard a monolithic couchdb database.
>>
>> The unfiltered replication was started from the futon replicator api, all 
>> the others from the command line using the ../_replicate call.  All 
>> replications are pull.
>>
>> The all work nicely, except that the replication between couchdb 1.1.1 and 
>> couchdb 1.2 seems to not write any checkpoints after a while:
>>
>> Checkpointed source sequence 911275, current source sequence 918089, 
>> progress 99%
>>
>> Is this to be expected?  Would an upgrade to couchdb 1.2 on the source 
>> system correct the issue?
>>
>>
>> I also think that the filtered replications, which don't involve couchdb 
>> 1.1.1, only checkpoint to the latest sequence that involves a document that 
>> passes the filter.  Even if new documents are added at the source and 
>> replicated to the target, a new checkpoint is not always written.
>>
>> Is this a known issue?
>>
>> How can I further narrow down the issue?
>>
>> Any documentation on the interplay of replication and checkpoints would 
>> helpful as well.  Thanks for your help.
>>
>> -- Andreas



-- 
Filipe David Manana,

"Reasonable men adapt themselves to the world.
 Unreasonable men adapt the world to themselves.
 That's why all progress depends on unreasonable men."

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