Couchbase http://www.couchbase.com/issues This file is an XML representation of an issue en-us 5.2.4 845 26-12-2012 [MB-4418] Allow disk write queue cap to be modified at runtime http://www.couchbase.com/issues/browse/MB-4418 Couchbase Server MB-4418 Allow disk write queue cap to be modified at runtime Improvement Major Resolved Fixed Public Mike Wiederhold Perry Krug Thu, 10 Nov 2011 22:42:21 -0600 Wed, 16 May 2012 18:16:19 -0500 Thu, 10 May 2012 18:31:08 -0500 1.8.0 1.8.1 couchbase-bucket 0 4 Integrated in github-ep-engine-2-0 #131 (See [<a href="http://qa.hq.northscale.net/job/github-ep-engine-2-0/131/">http://qa.hq.northscale.net/job/github-ep-engine-2-0/131/</a>])<br/> &nbsp;&nbsp;&nbsp;&nbsp; This behavior needs to be changed.<br/> <br/> The current method is to use &#39;-1&#39; to disable the cap completely, but there are a variety of problems with that including the fact that cbflushctl can&#39;t be used to actually set a -1:<br/> [<a href='mailto:perry@Membase1'>perry@Membase1</a> ~]$ /opt/couchbase/bin/cbflushctl localhost:11210 set tap_throttle_queue_cap &quot;-1&quot;<br/> usage: cbflushctl [options]<br/> <br/> cbflushctl: error: no such option: -1<br/> <br/> Please change it so that a value of &#39;0&#39; disables the cap We would rather fix cbflushctl in this case since it should be able to accept negative numbers. Setting the tap_throttle_queue_cap to -1 works in ep-engine. I also tried to set it at the Erlang level with: <br/> wget -O- --user=&lt;user&gt; --password=&lt;pass&gt; --post-data=&#39;ns_bucket:update_bucket_props(&quot;default&quot;, [{extra_config_string, &quot;tap_throttle_queue_cap=-1&quot;}]).&#39; <a href="http://localhost:8091/diag/eval">http://localhost:8091/diag/eval</a> <br/> <br/> And the memcached process failed to start with this message in the logs; <br/> <br/> [user:info] [2012-01-17 13:53:41] [<a href='mailto:ns_1@127.0.0.1'>ns_1@127.0.0.1</a>:&lt;0.8646.1&gt;:ns_port_server:handle_info:96] Port server memcached on node &#39;<a href='mailto:ns_1@127.0.0.1'>ns_1@127.0.0.1</a>&#39; exited with status 139. Restarting. Messages: Invalid entry, Key: &lt;tap_throttle_queue_cap&gt; Value: &lt;-1&gt; <br/> <br/> Since this works fine with a value other than -1, I assumed the problem was not just with cbflushctl... Reassigning to Jin, regarding the -1. we should also add this to documentation. <br/> adding MC to the ticket Integrated in github-ep-engine-2-0 #282 (See [<a href="http://qa.hq.northscale.net/job/github-ep-engine-2-0/282/">http://qa.hq.northscale.net/job/github-ep-engine-2-0/282/</a>])<br/> &nbsp;&nbsp;&nbsp;&nbsp;<a href="http://www.couchbase.com/issues/browse/MB-4418" title="Allow disk write queue cap to be modified at runtime"><strike>MB-4418</strike></a>: tap_throttle_queue_cap in cbflushctl takes &#39;infinite&#39; argument (Revision 7c4203378ab21f598247b88eefddf7d55e0bf124)<br/> <br/> &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Result = SUCCESS<br/> Mike Wiederhold : <br/> Files : <br/> * management/cbflushctl<br/> Date of First Response Fri, 11 Nov 2011 00:37:12 -0600 Rank 6025 Time In Status