Promise SanLink2

[Eric Notarnicola]

I just ordered a few of these from Small-Tree and they are FANTASTIC. Not only the smallest and lowest priced 10gbe t-bolt adapters, they are also hands down the QUIETEST. Nearly silent and perfect for use in an edit bay. Knowing they use a licensed rock solid Small-Tree driver is also reassuring.

[John Davidson]

Great because nothing sucks worse than having a room full of quiet SSD computers and then plugging in one of those old jet engines. Can’t wait for ours to get here.

John Davidson | President / Creative Director | Magic Feather Inc.

[Simon Blackledge]

Any speed test results anyone ?

[John Davidson]

So far we’re only getting about 167Mb read and about 200Mb read with a few peaks to 300 but it’s not as consistent or as fast as our ATTO TB1 boxes. The ATTO’s get about 800 Mb r/w. Granted, I haven’t had much time to work on them yet so perhaps Promise has more information.

John Davidson | President / Creative Director | Magic Feather Inc.

[Steve Modica]

A couple comments here:

1. A normal mac doesn’t have its tuning setup to deal with 10Gb very well. The window sizes are too small. (How it’s tuned can also depend on your destination. BSD doesn’t like to let a lot of packets go unacked, but linux seems to do much better with unacked packets)

I personally use these settings:

net.inet.tcp.doautorcvbuf=0
net.inet.tcp.doautosndbuf=0
kern.ipc.maxsockbuf=8388608
net.inet.tcp.sendspace=4000000
net.inet.tcp.recvspace=4000000
net.inet.tcp.maxseg_unacked=8
net.inet.tcp.delayed_ack=0
net.inet.tcp.win_scale_factor=7

2. Flow control has to be on everywhere. (802.3x). It has to be enabled everywhere and hopefully, everything negotiated to have it on. Systems have to both heed and send xon/xoff packets. Some switches (Cisco Catalyst) won’t send xoff. This is bad since any one element in the chain not pushing back will cause that element to drop packets when congestion occurs. That’s bad and leads to some really bad performance (similar to what you’re seeing).

Steve

Steve Modica
CTO, Small Tree Communications

[John Davidson]

Sorry it took me so long to respond Steve. We put that in and I had to clean up the coffee I spewed everywhere when the first test came back.

895 Mb Read and Write. And that’s with other people also accessing the server.

Anybody wanna buy some ATTO 10 Gbe TB1 boxes? I have two for sale.

John Davidson | President / Creative Director | Magic Feather Inc.

[John Davidson]

Kaboom. This is awesome.

John Davidson | President / Creative Director | Magic Feather Inc.

[Chris Duffy]

Bob, you need to get out of Florida and get up here to
visit us at Small Tree if you want to see more WOW stuff
you can use 🙂 Besides it will be getting too hot down
there soon….I’ll take you fishing up here and make some great
margaritas for you.

[Simon Blackledge]

Good to know.

Is that info just for NAS or is that something you can tweak in diver? Or OSX ?

Cheers

Si

[Steve Modica]

The sysctl settings are OSX.
The flow control settings are hardware level, so they get set in the driver. Unfortunately, every piece of gear and OS is a little different, so how you set flow control sometimes requires a look at the manual. We enabled it by default, but it can be set manually in the Network->Advanced->Hardware tab (it goes with “full duplex”)

Steve Modica
CTO, Small Tree Communications