[DRBD-user] slow sync speed

[Adam Weremczuk]

"Max-buffers 8k" appear to be the sweet spot for me.
I'm now getting 145-150 MB/s transfer rates between nodes which I'm 
happy with.
The biggest problem was I didn't have "syncer" section defined at all.

Currently my fully working and behaving config looks like below:

global { usage-count no; }
common { protocol C; }
resource r0 {
   disk {
     on-io-error detach;
     no-disk-flushes;
     no-disk-barrier;
     c-plan-ahead 0;
   }
   net {
     max-buffers 8k;
   }
   syncer {
     rate 150M;
     al-extents 6400;
   }
   on lion {
     device /dev/drbd0;
     disk /dev/sdb1;
     address 192.168.200.1:7788;
     meta-disk internal;
   }
   on tiger {
     device /dev/drbd0;
     disk /dev/sdb1;
     address 192.168.200.2:7788;
     meta-disk internal;
   }
}

On 11/10/18 15:06, Robert Altnoeder wrote:
> On 10/11/2018 03:56 PM, Oleksiy Evin wrote:
>> Try to remove the following:
>>
>> c-fill-target 24M;
>> c-min-rate 80M;
>> c-max-rate 720M;
>>
>> sndbuf-size 1024k;
>> rcvbuf-size 2048k;
>>
>> Then gradually increase max-buffers from 4K to 12K checking its impact
>> to the sync speed. Make sure you have the same config on both nodes
>> and apply the changes with "drbdadm adjust all" on both nodes too.
>>
>>