[DRBD-user] Performance Issues on version 8.3.13

[GG-Net Mailing]

Hello,

i'm running drbd on two Debian Wheezy x64 servers.

I'm using protocol A for asynchronous sync, since one of the machines has a hybrid RAID10 on an adaptec 71605Q. Build of 2x 3TB Seagate Constellation CS SED and 2x Samsung 840 500GB. And the other only has a plain 1TB HDD.

If I run a simple dd test on the node with the RAID copying from /dev/zero to a file on the device with drbd disabled, I get results around 400mb/s.

The moment I start drbd with the node as primary and run the test again, my results are roughly 110mb/s.

Are there any known issues regarding this?

My configuration file for DRBD:

global { usage-count no; } 
common {

  startup {
    wfc-timeout 0;
    degr-wfc-timeout 120;
    }
  disk {
    on-io-error detach;
        no-disk-flushes;
        no-md-flushes;
        no-disk-barrier;
    }
}
resource r0 {     protocol A;
  syncer {
    rate 60M;  }
  net {
   after-sb-0pri disconnect;
   after-sb-1pri disconnect; 
   after-sb-2pri disconnect; 
   }
  startup {
  }

  on jetfire { 
    device /dev/drbd0; 
    disk /dev/sda3; 
    address 192.168.253.1:7788
    flexible-meta-disk internal; 
  }

  on jetstorm {
    device /dev/drbd0;
    disk /dev/sda3;
    address 192.168.253.2:7788;
    flexible-meta-disk internal;
  }
}

Thanks in advance

kind regards

Tim Rohwedder