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From Antony Blakey <antony.bla...@gmail.com>
Subject Re: Attachment Replication Problem - Bug Found
Date Sun, 17 May 2009 00:53:51 GMT

On 17/05/2009, at 12:09 AM, Adam Kocoloski wrote:

> So, I think there's still some confusion here.  By "open  
> connections" do you mean TCP connections to the source?  That number  
> is never higher than 10.  ibrowse does pipeline requests on those 10  
> connections, so there could be as many as 1000 simultaneous HTTP  
> requests.  However, those requests complete as soon as the data  
> reaches the ibrowse client process, so in fact the number of  
> outstanding request during replication is usually very small.  We're  
> not doing flow control at the TCP socket layer.

IIUC, given that no attachments bodies are consumed by the replicator  
until the documents are checkpointed, it's possible for the replicator  
to block if the number of pending attachments in a checkpoint buffer  
is greater than the ibrowse concurrent request limit. In a case like  
mine, with many attachments on very small documents, this is very  
likely. Or am I still confused? :/

Antony Blakey
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