Register for the iXsystems Community to get an ad-free experience and exclusive discounts in our eBay Store.

8.0.4: Optimizing buffer settings

bal0an

Newbie
Joined
Mar 2, 2012
Messages
30
When googling FreeBSD for advice on improving network performance I found the following:

kern.ipc.maxsockbuf=4000000
net.inet.tcp.sendbuf_max=16777216
net.inet.tcp.recvbuf_max=16777216
net.inet.tcp.sendspace=65536
net.inet.tcp.recvspace=65536
net.inet.udp.recvspace=65536

Any assessment or experience with changing those settings to improve network throughput?

Unfortunately I didn't document the improvements when making those adjustments half a year ago. If I remember correctly there was a few percent increase with throughput.

Regards, Andreas

Hostname freenas.local
FreeNAS Build FreeNAS-8.0.4-RELEASE-x64 (10351)
Platform Intel(R) Core(TM) i3-2100T CPU @ 2.50GHz
Memory 7899MB
System Time Sat Mar 3 21:22:43 2012
Uptime 9:22PM up 9:24, 0 users
Load Average 0.99, 0.34, 0.22
OS Version FreeBSD 8.2-RELEASE-p6
 

gcooper

FreeNAS Experienced
Joined
Sep 23, 2011
Messages
416
net.inet.tcp.sendspace=65536
net.inet.tcp.recvspace=65536
net.inet.udp.recvspace=65536
You don't want to mess with these because it screws up the algorithm used by the network stack for determining how large or small your send/receive buffers should be (this is according to a discussion I've had with other iX devs).

I'd have to look at these settings in the kernel before giving an official recommendation on what to do in a more generic manner (I have a general idea, but not something that can be properly articulated).
 
Top