Wireless performance

[lovegnome]

Has anyone actually taken a good look at why extraction via wireless is so slow?

Here's what I know. I've got two friends with tivos connected via wet11s and they each get less than 500kb/s doing extraction with tytool v6.

I've confirmed this on my network. My tivo is hardwired via a turbonet card and I'm getting around 1.5Mb/s to my wired computers, under 500kp/s to my laptop via wireless. Confirmed same/worse performance with mfsstream.

So what's the deal? Has anyone actually put a packet sniffer on the job yet?

Note: Now that tytool6 multiplexes output, I can watch shows directly off the tivo onto my wired machines using VideoLan to open the files as soon as they start extracting. It would be nice to enjoy some television on my porch using my laptop, but perfomance is not fast enough.

Also, a 'View' button in tytool that piped the output straight to Videolan would be awfully cool!!!!

[BubbleLamp]

Originally posted by lovegnome
Has anyone actually taken a good look at why extraction via wireless is so slow?

Here's what I know. I've got two friends with tivos connected via wet11s and they each get less than 500kb/s doing extraction with tytool v6.

I've confirmed this on my network. My tivo is hardwired via a turbonet card and I'm getting around 1.5Mb/s to my wired computers, under 500kp/s to my laptop via wireless. Confirmed same/worse performance with mfsstream.

So what's the deal? Has anyone actually put a packet sniffer on the job yet?

Note: Now that tytool6 multiplexes output, I can watch shows directly off the tivo onto my wired machines using VideoLan to open the files as soon as they start extracting. It would be nice to enjoy some television on my porch using my laptop, but perfomance is not fast enough.

Also, a 'View' button in tytool that piped the output straight to Videolan would be awfully cool!!!!

Because wireless sucks and the "11Mbps" it's rated for is a pipe dream.

[lovegnome]

Ah yes.

And before we have a spat of more "wireless sucks" posts, let's be clear that I can download to my laptop from other sources at much better than the 1.5Mb/s rate the tivo is capable of.

So while wireless may actually suck, it doesn't suck 500kb/s worth. Looking for another problem.

[BubbleLamp]

Originally posted by lovegnome
Ah yes.

And before we have a spat of more "wireless sucks" posts, let's be clear that I can download to my laptop from other sources at much better than the 1.5Mb/s rate the tivo is capable of.

So while wireless may actually suck, it doesn't suck 500kb/s worth. Looking for another problem.

Then you might be suffering from the bug in Tytools. Try an ftp from the Tivo and see what kind of throughput you get.

[lovegnome]

Nope.

Both tyhttp (mfsstream) and tivoftpd give 1.2Mb/s or better via wired, under 500kb/s via wireless.

Also, just for kicks, I booted my laptop over to debian to make sure it wasn't a Windows XP networking oddity. Same performance w/ tyhttp and ftp.

Unless all three pieces of software suffer from the same networking bug (which is a remote possibility) I would guess it's either an oddity with the tivo's networking code, or maybe (far less likely) that it's a flaw in the turbonet driver?

I should mention, I'm using Tivo's 3.0 turbonet driver.

My main point, is that a lot of people have been assuming their poor performance is due to wireless connectivity (low signal, etc). This is not true in my case.

So back to my original question...has anyone sniffed any packets looking for excessive retries or something else the tivo networking code may not be handling correctly?

[neuroman]

Originally posted by lovegnome
Nope.

My main point, is that a lot of people have been assuming their poor performance is due to wireless connectivity (low signal, etc). This is not true in my case.

So back to my original question...has anyone sniffed any packets looking for excessive retries or something else the tivo networking code may not be handling correctly?

I'm running WinXP Pro and WinXP Home on to separate laptops wirelessly. Performance is actually pretty good with my D-Link Wireless Access Point. One of my wireless NICs is a Compaq WL110 and the other is a WL100. Both have configurable paramters to adjust for low speed (2Mbit) or high speed (11Mbit) transmission speeds.

On my Tivo I am using a Zoom Air 4105 Wireless NIC with Externa antenna and I'm getting extremely slow throughput. My guess is the network stack on the Tivo version of Linux is not set for peak wireless performance. It may be tuneable or not. I'm not experienced with Linux networking so I don't have a clue. Maybe someone who is can hazard a guess or suggestion?

[ronnythunder]

lovegnome, do a search here for "jafa"; he's the guy that created turbonet, and he's mentioned some issues with the tivo tcp stack and there's also a relatively recent turbonet driver update that sounds like it may be part of your problem. specifically, the update fixes a problem that can cause excessive retransmissions.

ronny

[lovegnome]

Originally posted by ronnythunder
lovegnome, do a search here for "jafa"; he's the guy that created turbonet, and he's mentioned some issues with the tivo tcp stack and there's also a relatively recent turbonet driver update that sounds like it may be part of your problem. specifically, the update fixes a problem that can cause excessive retransmissions.

ronny

No joy.

1. Interesting enough, search for user name "jafa" only turns up one post for me. I know he's posted more...I've been lurking around for a while.

2. I've replaced the stock driver with the latest turbonet driver with no improvement in performance.

[BubbleLamp]

Originally posted by lovegnome
No joy.

1. Interesting enough, search for user name "jafa" only turns up one post for me. I know he's posted more...I've been lurking around for a while.

2. I've replaced the stock driver with the latest turbonet driver with no improvement in performance.

jafa hangs out on the avs forums.

I have explained what the packet problem was, (and still is for some) in this thread. Basically on a ~10Mb/s connection, the small packet size swamps the available bandwidth.

[Stephen]

Heck 500k is pretty good.. I can just get that ftping from one machine to another on my wireless network... (40 ft away from each other)

[Schnitty]

bubblelamp -- i read your other thread and found it very informative. however, you asked jdiner to do some investigation for you and you even mentioned doing more yourself. any update on those efforts? was there any relatively obvious settings that could be changed to fix this?

[BubbleLamp]

Originally posted by Schnitty
bubblelamp -- i read your other thread and found it very informative. however, you asked jdiner to do some investigation for you and you even mentioned doing more yourself. any update on those efforts? was there any relatively obvious settings that could be changed to fix this?

The change jdiner made was to add the double-socket option. That seemed to work for some number of folks. I don't know where the SACK issue fits in all of this, but I suspect it's another "to be resolved" issue. He'd be the one to ask.

[AlphaWolf]

If you realy wanted wireless, wouldn't it be both cheaper and faster to just install a regular turbonet and then bridge it to wifi?

/me shrugs

My tivo is turbonet wired to a 54mbit (802.11g) wireless switch. Turbonet cost $69, switch cost $112, but I use it for other things as well. You could just get a regular bridge for ~$69...

Btw, my stream download speeds are in the ~1400k/sec over wifi...laptop is on a linksys 54mbit card I got for $50 opened box at best buy.

<brag> as I type this I am sitting in my school cafeteria with no wires </brag>

[lovegnome]

Originally posted by AlphaWolf
If you realy wanted wireless, wouldn't it be both cheaper and faster to just install a regular turbonet and then bridge it to wifi?

/me shrugs

My tivo is turbonet wired to a 54mbit (802.11g) wireless switch. Turbonet cost $69, switch cost $112, but I use it for other things as well. You could just get a regular bridge for ~$69...

Btw, my stream download speeds are in the ~1400k/sec over wifi...laptop is on a linksys 54mbit card I got for $50 opened box at best buy.

<brag> as I type this I am sitting in my school cafeteria with no wires </brag>

That's interesting information.

Most of the people I know _are_ using turbonet cards and wireless bridges. I , myself, have my tivo hardwired to the network, but only experience slow performance when pulling video via the wireless laptop. Similiar results with my friends' WET11 wireless bridge.

Your experience makes t looks like the higher bandwidth allowed by 801.11g will handle the saturation problem seen by Bubblelamp. That's useful information.

[Schnitty]

Originally posted by AlphaWolf
If you realy wanted wireless, wouldn't it be both cheaper and faster to just install a regular turbonet and then bridge it to wifi?

/me shrugs

My tivo is turbonet wired to a 54mbit (802.11g) wireless switch. Turbonet cost $69, switch cost $112, but I use it for other things as well. You could just get a regular bridge for ~$69...

Btw, my stream download speeds are in the ~1400k/sec over wifi...laptop is on a linksys 54mbit card I got for $50 opened box at best buy.

<brag> as I type this I am sitting in my school cafeteria with no wires </brag>

alphawolf -- very good info. i'm actually thinking of upgrading my 802.11b to a "g" network. what switch did you get for $112? i have an ok 802.11b to ethernet bridge (dlink) -- which companies are making "g" bridges?