<html dir="ltr"><head></head><body style="text-align:left; direction:ltr;"><div>If I'm not wrong, the "syncer" section has been deprecated somewhere around 8.4.0 drbd version. Based on the logs you provided the version you use is 8.4.10, so I don't think that should have any speed impact. But I'm glad you've got it resolved. </div><div><br></div><div>//OE</div><div><br></div><div>-----Original Message-----</div><div><b>From</b>: Adam Weremczuk <<a href="mailto:Adam%20Weremczuk%20%3cadamw@matrixscience.com%3e">adamw@matrixscience.com</a>></div><div><b>To</b>: Robert Altnoeder <<a href="mailto:Robert%20Altnoeder%20%3crobert.altnoeder@linbit.com%3e">robert.altnoeder@linbit.com</a>></div><div><b>Cc</b>: <a href="mailto:drbd-user@lists.linbit.com">drbd-user@lists.linbit.com</a></div><div><b>Subject</b>: Re: [DRBD-user] slow sync speed</div><div><b>Date</b>: Wed, 17 Oct 2018 10:05:10 +0100</div><div><br></div><pre>"Max-buffers 8k" appear to be the sweet spot for me.</pre><pre>I'm now getting 145-150 MB/s transfer rates between nodes which I'm </pre><pre>happy with.</pre><pre>The biggest problem was I didn't have "syncer" section defined at all.</pre><pre><br></pre><pre>Currently my fully working and behaving config looks like below:</pre><pre><br></pre><pre>global { usage-count no; }</pre><pre>common { protocol C; }</pre><pre>resource r0 {</pre><pre> disk {</pre><pre> on-io-error detach;</pre><pre> no-disk-flushes;</pre><pre> no-disk-barrier;</pre><pre> c-plan-ahead 0;</pre><pre> }</pre><pre> net {</pre><pre> max-buffers 8k;</pre><pre> }</pre><pre> syncer {</pre><pre> rate 150M;</pre><pre> al-extents 6400;</pre><pre> }</pre><pre> on lion {</pre><pre> device /dev/drbd0;</pre><pre> disk /dev/sdb1;</pre><pre> address 192.168.200.1:7788;</pre><pre> meta-disk internal;</pre><pre> }</pre><pre> on tiger {</pre><pre> device /dev/drbd0;</pre><pre> disk /dev/sdb1;</pre><pre> address 192.168.200.2:7788;</pre><pre> meta-disk internal;</pre><pre> }</pre><pre>}</pre><pre><br></pre><pre>On 11/10/18 15:06, Robert Altnoeder wrote:</pre><pre></pre><pre>On 10/11/2018 03:56 PM, Oleksiy Evin wrote:</pre><pre></pre><pre>Try to remove the following:</pre><pre><br></pre><pre>c-fill-target 24M;</pre><pre>c-min-rate 80M;</pre><pre>c-max-rate 720M;</pre><pre><br></pre><pre>sndbuf-size 1024k;</pre><pre>rcvbuf-size 2048k;</pre><pre><br></pre><pre>Then gradually increase max-buffers from 4K to 12K checking its impact</pre><pre>to the sync speed. Make sure you have the same config on both nodes</pre><pre>and apply the changes with "drbdadm adjust all" on both nodes too.</pre><pre><br></pre><pre><br></pre><pre></pre><pre></pre><pre><br></pre><pre>_______________________________________________</pre><pre>drbd-user mailing list</pre><pre><a href="mailto:drbd-user@lists.linbit.com">drbd-user@lists.linbit.com</a></pre><pre><a href="http://lists.linbit.com/mailman/listinfo/drbd-user">http://lists.linbit.com/mailman/listinfo/drbd-user</a></pre><pre><br></pre></body></html>