New MyBook Duo 4Tb astonishingly slow... I mean, really soul-numbingly slow

Legacy Products My Book Live
14

Sebi,

Something is wrong with your setup. Are you willing to “tune” your AFP client settings on your iMac to improve performance? I am getting an average of 30Mbps via AFP for Time Machine and 40Mbps+ via Samba.

My setup as follow:

  • MacBook Pro 2.4Ghz Intel Core i5, 4GB RAM 1067MHz DDR3 on Mac OS X 10.7.4
  • TP-Link TL-WR1043ND Wireless Gigabit router
  • Gigabit Ethernet connection from MacBook Pro to LAN

APF client on MacBook Pro tuned due to the “delay” caused by a little-known interaction between Nagle’s Algorithm and Delayed ACK. For a detailed description of the problem please read this article.

To fix it, do the following:

  1. Open a terminal window o your Mac OS X and type:

    su -

    (to switch to user root

   

    password: ******** (whatever your password is)

   

    vi /etc/sysctl.conf

OR use whatever editor you feel most comfortable with to create or modify: /etc/sysctl.conf

  1. Enter the following lines in the config file /etc/sysctl.conf;

net.tcp.delayed_ack=2
net.inet.tcp.sendspace=2097152
net.inet.tcp.recvspace=2097152
net.inet.tcp.maxseg_unacked=32

Now, reboot your iMac and test the data throughput and share your outcome. If this solves your challenge, please click “Problem Solved”. 

Regards,

Moonshi

2 Likes