Hi,<div><br></div><div>(Running rabbit 2.8.0)</div><div><br></div><div>We're experiencing weird behavior from the statistics/management module.</div><div>Every x seconds, we take a snapshot of the statistics and send this to a Graphite server, giving us the following data:</div>
<div><br></div><div><img src="cid:ii_13ad4dd4953b2bc3" alt="Inline image 2" width="780" height="204"><br></div><div><br></div><div>As you can see, the delivery (no-ack) rate drops to 0 every hour for a couple of minutes. Other statistics on message processing indicate that actual delivery/consuming is continuing, so it looks like it's really only the statistics that are wrong.</div>
<div><br></div><div>If I look at the json output during such a 'downtime' I can see that the publish rate is always available, but the rest of the rates (acknowledge, delivery, etc) are mostly 0. </div><div>I understand a bit from the sources that in this /api/overview call from the management api, these statistics are gathered from different places, both memory and database (with additional calculations executed on them while fetching), correct?</div>
<div>Could it be that some of these values are 0 because of certain time-outs while getting the data? In other words: do I have to start searching for the problem at the database disk/IO level?</div><div><br></div><div>I couldn't see any IO waits on the machine indicating something else is happening at the time. Also CPU load is normal. </div>
<div>Still the weird thing is that this also happens on a test machine at roughly the same times. </div><div>Since both machines are VM's, this might indicate that it could be an infrastructural problem, but I'd like to be sure before accusing 'others'.</div>
<div><br></div><div>Thanks for the analysis help.</div><div><br></div><div>- Irmo</div>