Mailing-List: contact user-help@accumulo.apache.org; run by ezmlm
Precedence: bulk
Reply-To: user@accumulo.apache.org
Received-SPF: pass (athena.apache.org: domain of josh.elser@gmail.com
 designates 209.85.216.41 as permitted sender)
Message-ID: <52FA84BC.1040902@gmail.com>
Date: Tue, 11 Feb 2014 15:14:52 -0500
From: Josh Elser <josh.elser@gmail.com>
User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.9;
 rv:24.0) Gecko/20100101 Thunderbird/24.2.0
MIME-Version: 1.0
To: user@accumulo.apache.org
Subject: Re: Number of running scans seems limited
References: 
 <CA+zmODj5sqVp6NTkYhtvOHYFEUYBO0K6SYn9LQPG4Csx9pbp_A@mail.gmail.com>
In-Reply-To: 
 <CA+zmODj5sqVp6NTkYhtvOHYFEUYBO0K6SYn9LQPG4Csx9pbp_A@mail.gmail.com>
Content-Type: text/plain; charset=ISO-8859-1; format=flowed
Content-Transfer-Encoding: 7bit

It depends. First off, there's the number of scanners and threads given 
to batchscanners which control how many client "scan sessions" are 
incoming to the cluster.

Some discussion on an earlier thread might help: 
http://mail-archives.apache.org/mod_mbox/accumulo-user/201402.mbox/%3C52F542E5.90002%40gmail.com%3E

If you have "dense" tablets where you're scanning for multiple Ranges 
which are all co-located on the same tablet, I believe that those 
multiple Ranges that lie on a single tablet (within one ScanSession) 
will be binned together and then run sequentially, so you wouldn't see 
server-side concurrency there.

On 2/11/14, 2:59 PM, Roshan Punnoose wrote:
>  From the monitor, it seems like only N "Running Scans" are allowed at a
> time, and the rest are queued. Is this something that is configurable?
>
> Roshan