Buffering - Slow LAN speed - Half duplex ?

[jecepede]

Aloha !


Right of the bat I wanna thank the creators for the XBMC4Xbox version I'm running now.
It is the aweseome version : XBMC4Xbox 3.5-DEV-r32663 (Compiled: Jan 4 2014)
Already clicked the little thumbsup but an extra thanks can never hurt right....

Anyway I have a small question about the speed of the LAN on the Xbox.

I have been using XBMC for as long as I can remember and it has always worked fine but lately
it started pausing the video with the message "Buffering". It usually does it with more "complex"
vid-containers like the example below :

Code: Select all

The Hobbit An Unexpected Journey - Extended Version - HDRIP AC3.avi
===

Video
---
Length          : 03:02:27
Framewidth      : 1280
Framehight      : 528
Bitrate         : 3164 kbps
Totale bitrate  : 3548 kbps
Framespeed      : 23 frames per seconde

Audio
---
Bitrate             : 384 kbps
Channels            : 6
Audiosampelspeed    : 64 kHz

What I found out is that the NIC is only running on 100Mb half duplex. Since I also found out there
was a new build, made in jan 4th, I descided to start from scratch.
I Erased my entire XBOX. All partitions were formatted (with the exception of C:)
Then I installed XBMC4Xbox 3.5-DEV-r32663 and added the win32 drivers.
As epected, it works like a charm.

To be on the safe side;
In "System" -> "settings" -> "System" I have doubled ALL the cache setting in the
the menu's "DvDPlayer cache"en "MPlayer cache".
(With the exception of the "Audio cache" & "Audio cache - max time"...)


-> Now here is the thing. My Xbox still runs at 100Mb, half duplex and if I get the information
about CPU and such I get the following values :

Code: Select all

FreeMem   : Between 10.000 KB and 11.000 Kb
FPS       : About 24.0 fsp
CPU       : Between 54% and 92%
Cache     : Between 11% and 100%

For now, I didn't see it buffering again. But since the cache falls back to 11% it will
only be a matter of time before it probably will start buffering and take the joy
out of "enjoying a movie"...


---
On a side note, copying anything to my Xbox takes for ever.
I time about 19 minutes for 5.3 Gb of data via SMB
and a staggering 20 minutes for only 1.1 gb of data via FTP !
---


Am I missing something here ??? What did I do worng ????




Cheeeeeeeeers everybody



Jecepede

[AZImmortal]

But since the cache falls back to 11%

Are you referring to the stat line that starts with "CPU"? If you are, then that's for CPU usage (as the name should imply, heh), not for how much cache is remaining. You want the CPU usage to be as low as possible, but an upper rate of 100% is normal and expected. As for your network problems, it's likely not a problem with XBMC or your Xbox unless you're saying that you used to run at full duplex with the exact same setup that you're using now. How exactly is your network set up?

[jecepede]

Aloha AZImmortal,

Oops, my bad...
I should of have typed :

Code: Select all

FreeMem   : Between 10.000 KB and 11.000 Kb
FPS       : About 24.0 fsp
CPU       : Between 54% and 92%
Cache     : Between 11% and 100%

Now the numbers suddenly make more sence. (I changed the original post as well.

---

As for my network.

I am not sure I understand the question. What would you like to know ?
It is a fairly standard setup. Below is a simplyfied schematic :

Code: Select all

                    ------------            ------------
                    |FileServer|            |Work PC   |
                    ------------            ------------
                         |                       |
------------        ------------            ------------
| Firewall |--------|Switch1   |---/wall/---|Switch2   |
------------        ------------            ------------
                                                 |
                                            ------------
                                            | XBOX     |
                                            ------------

The switches are (to my knowledge) real switches, not HUB's, and have a speed of 10/100 Mb






Cheeeeeeeeeeeers mate !


Jecepede

[Heimdall]

How do you know it's running at half duplex?

[jecepede]

How do you know it's running at half duplex?

Hi Heimdal,

You can check the settings in XBMC4Xbox.

Just go to "Settings" -> "System info" and then choose "Network information".
Here I read the following info on my Xbox :

Type : DHCP
Link: 100mbps Half duplex
Mac address: 11 22 33 44 55 66
IP address: 10.0.1.81
Subnetmast: 255.255.25..0
Gateway: 10.0.1.1
Primary DNS: 10.0.1.1
Secondary DNS: 8.8.8.8
Internet: Connected


I also tried a static setting. But that didn't chanhe anything, except the value : type



Cheeeeeeeeeeeeeeer


Jecepede

[AZImmortal]

That schematic is exactly what I was looking for. I also asked if you used to run at full duplex in the past (I didn't actually phrase it in the form of a question though so you might have overlooked it). Is the answer yes?

[Heimdall]

Hi Jecepede

I wasn't asking how to do it, I was asking how you had done it! You'd be surprised how many people manage to make 2+2=5, and create imaginary "reasons" as to why something isn't working. It's good to know you aren't one of them!

The real question now is: why are your switch and Xbox only negotiating half duplex instead of full duplex? I doubt that it's causing the problem you are seeing, but it might point us in the right direction.

Can you try a different port on the switch, or maybe plug the Xbox directly into a laptop Ethernet port, and see if the Xbox negotiates a full duplex link?

[Dan Dar3]

Aside from the half-duplex issue, I notice your DNS servers - the primary one is your gateway and the second one is Google's. You might want to maybe change that in your router and only send the first one, and let the router cache DNS entries and all that, maybe you can configure that your router uses internally the Google DNS server(s) for external addresses.

This might be nothing as the primary will probably answer happily all DNS queries coming from Xbox, and never ask the secondary for anything - but if it does, and it asks it for internal names, that'll incur an unnecessary delay with no useful response.

[jecepede]

Ho ho ho Everyone,

Sorry for the late reply, I have been out of town for the weekend...


@AZImmortal

Actually I have no idea if it has ever run in full duplex.
I just noticed it was running in half duplex with the XBMC4Xbox version I have installed now.


=== === ===


@Heimdall

"I was asking how you had done it!"

I am very sorry about that. Being a former sysop/administrator/moderator it is just force of habit
typing an answer like that. Please do not be mad... it will not happen again


Anyway, I have been searching for network- and disc problems as well and I found the
following two programs to test the HDD speed and the connection between "FileServer" and "WorkPC".

http://www.hdtune.com/
http://www.totusoft.com/lanspeed1.html

First I checked the speed of my HDD from "FileServer". Since this HDD is a spanned
volume (120 Gb + 40 Gb + 40 Gb) it makes sense to assume it will be as fast as the slowest disc.

In my case it is a WD 40 Gb disc. It is an IDE and should have a theoretical
speed of about 66 Mb/sec (according to the manufacturer).

It was 65 Mb/s (Wow ?!?).

---

Then I tested my network performance using Lan Speed.
I used a file size of 1 Gb (1024 Mb). This size is 100% sure not to sneak into
a buffer somewhere and for good measures I did the test three times.

I found an average of :

Read : 64 Mb/s
Write : 62 Mb/s

This should be about : (62 /8) * 1024 = 7936 MB in XBMC4Xbox's filemanager.

For real however, when I copy from "FileServer" to "XBMC4Xox" I only
get speeds of +/- 4400.00 KB/s (min 3700 KB/s, max 5100 KB/s)


As for trying a different port. I will try this later. Thanx for the suggestion.
Why did I not think of that **bangs forehead against wall**


=== === ===


And last but not least @Dan Dar3

Hi and thanks for pointing that our for me. The 8.8.8.8 was still from a previous
setup I used to had. My primary DNS was from my provider.
I ereased from the firewall-config. Now the XBMC4Xbox says :

Secondary DNS: 0.0.0.0



Ok cheeeeeeeeeeeers everyone and thank you for trying to help....


Jecepede

[jecepede]

Ho ho ho everyone...

I have just tried the suggestion made by Heimdall by trying a different port on "Switch2"

Thus there I sat under my desk and pulled the cable from one port into another port.
The little 100Mb light came up again so I started to climb out of the tiny space under my desk.
While climbing my eye glanced over the name of the Switch :

SuperStack II Baseline Dual Speed Hub 24-Port TP (3C16593A)


-----> Ehhr... hang on, a HUB, not a switch ???


Then I remembered my boyscout-motto : "If everything else fails, Read The eFfing Manual"
It clearly stated the following :

All ports on the Baseline Dual Speed Hub are half duplex,
autosensing 10 Mbps and 100 Mbps.

Well at least THAT explains why my Xbmc4Xbox only connects with half duplex.
Should be ok thow co'z file transfer from "FileServer" to "WorkPc" is generally round 64 Mb/s
and the network path includes the switch AND the hub.


Unless............ the Xbox's HDD is really really slow ????



Can anyone tell me about access speeds of the HDD of the Xbox ?
I can imagine that the HDD can't keep up with caching the video's while playing.




Cheeeeeeeeeeeeeeeeeers


Jecepede

[AZImmortal]

I'm sure that the problem isn't with the hard drive speed. It's possible that the problem is that the Xbox is somehow sending data back over the network during playback, and since the link is half duplex, then it interrupts streaming to the Xbox. If you have another switch (or a router that can act as a switch), then I'd suggest trying that.

[jecepede]

Aloha AZImmortal,


Thanx for you reply.

Your answer does seem to make a lot of sence. Afterall, streaming data uses bi-directional network traffic.
If the stream gets interrupted long enough, cache will be empty in just a short period of time.

It does however raise the question why I can stream from my "FileServer" to my "WorkPC" using XBMC for Windows
without ever noticing a hich in the video... That connection is half duplex as well...

If you have another switch (or a router that can act as a switch), then I'd suggest trying that.

I will most certainly do that but, how to put it mildly, my current financial status prohibits me from purchasing any peripheral hardware.
In other words : Ain't Got No Dough


In my first post I wrote :

For now, I didn't see it buffering again. But since the cache falls back to 11% it will
only be a matter of time before it probably will start buffering and take the joy
out of "enjoying a movie"...

So before I get another switch, a REAL switch, I'll end up with trippleling the cache.
I have no idea if it will help, but at least I have the idea that I tried something



Cheeeeeeeeeeeers Mate !



Jecepede

[AZImmortal]

I'm not sure why your other machines don't exhibit this problem. Maybe the Xbox handles streaming traffic differently? I'm not sure. I guess it's possible that the Xbox's resources are too limited compared to a full computer to handle half duplex limitations well.

I'm viewing this on my phone right now and your schematic doesn't seem to be formatting correctly in mobile browsers (not your fault), but if it's possible, you can take your existing router and temporarily put it in place of your hub if you'll still be able to route correctly between the Xbox and file server. This way we can at least confirm whether or not things work correctly on full duplex.

[jecepede]

Hi AZImmortal,


I am not sure I understand what you mean with "take your existing router and temporarily put it in place of your hub" ?
Did you mean switch the switch with the hub ? I could try that.

If it works I could buy a new switch and put the old HUB in the mothballs...
It's also a plus for the rest of my network


Cheeeeeeeeeeers mate !

Jecepede

[AZImmortal]

What I meant was to take what you labeled as "Firewall" in your schematic (I'm assuming that this is a router?) and temporarily using it in place of your hub (Switch2) so that you only have proper switches between your Xbox and your file server. Alternatively, you can temporarily put your file server where your work PC is and switch your hub and your switch so that once again you only have a switch (and not a hub) between your file server and Xbox.

[jecepede]

Aloha AZImmortal,

Ohhh that is what you meant.
Both would be nice idea's to try however, I don't think the mrs would like me "destroying" the home network for a simple test.


Btw, I found some new info on the web. The HD-Tune graph of the HDD in my particular XBOX :
Here you can see the max data troughput of the disk, 29.2 Mb
This is about 3737.6 MB/s (29.2 /8 * 1024 ) and is smack-bang in the middle of the XBMC-filemanager tests.

ST310014A - Speedtest

So my careful conclusion :
---
HD-like video + Half duplex connection + Slow Xbox HDD (no internal memory caching) = Buffering



Since I wanna buy a new computer anyway (saving up money for that)
I think I'll go the extra mile and buy a real switch to go with it.
This will take a number of weeks but I'll promise I'll get back to you with the result..



For now, thanks everybody for supporting me with idea's



Cheeeeeeeeeeeeeer

Jecepede

[BuZz]

the HD speed is in megabytes/second. you don't need to convert it. your problem is unlikely related to the hd. it is more likely related to networking issues. I suggest plugging the xbox directly into the switch with the fileserver and testing from there.

[AZImmortal]

Yeah, it's extremely unlikely that the problems you're experiencing have anything to do with the Xbox's hard drive. Also, it shouldn't take much effort to temporarily relocate your router to where your hub is.

[jecepede]

Ho ho ho !

the HD speed is in megabytes/second. you don't need to convert it.

You are correct however, I try to get everything as clear as I can get it for myself so I stick to one unit.
In that way I can't get confused and accidentally compare apples and oranges

Yeah, it's extremely unlikely that the problems you're experiencing have anything to do with the Xbox's hard drive. Also, it shouldn't take much effort to temporarily relocate your router to where your hub is.

This morning I got a Eureka-moment.
I did an incredibly simple test. I hung my laptop directly on the cable where normally my Xbox is connected.
So I measured to-and-fro my "FileServer" <-> "Switch1" <-> "Hub" <-> "XboxCable" <-> "Laptop, instead of Xbox"

Here are the speed results :
---
Writing to "FileServer" : 57.6 Mpbs (In XboxFilmanager terms : 7202 MB/s)
Reading from "FileServer" : 64.5 Mbps (In XboxFilmanager terms : 8069 MB/s)

Then I streamed "The Hobbit An Unexpected Journey - Extended Version - HDRIP AC3.avi"
via XBMC 12 Eden for Windows. Not a single glitch.... Not sure this is an honest comparison but still.... no buffering....



Anyway: Seeing these results, my previous humble cautious preliminary conclusion still stands.
---
HD-like video + Half duplex connection + Slow Xbox HDD (no internal memory caching) = Buffering, sometimes.



But there is still a lot of things running in my mind :
- Can anyone do a XboxFilemanager copy from a SMB share and post the speed ?
- What will happen when I exit the HUB and enter the Switch ?
- Can't I buffer to internal memory instead of HD ? cachemembuffersize ?
- Why have I never seen it buffer a DVD, DVD players are slower then HDD's ? Lower bitrate perhaps ?



Ok that is it for now....

I'll keep you posted, how I'll try to get the slowness out of my network (if there is any)


Cheeeeeeeeeeeeeeeeeeers


Jecepede

[BuZz]

Ho ho ho !
You are correct however, I try to get everything as clear as I can get it for myself so I stick to one unit.
In that way I can't get confused and accidentally compare apples and oranges

This morning I got a Eureka-moment.
I did an incredibly simple test. I hung my laptop directly on the cable where normally my Xbox is connected.
So I measured to-and-fro my "FileServer" <-> "Switch1" <-> "Hub" <-> "XboxCable" <-> "Laptop, instead of Xbox"

Here are the speed results :
---
Writing to "FileServer" : 57.6 Mpbs (In XboxFilmanager terms : 7202 MB/s)
Reading from "FileServer" : 64.5 Mbps (In XboxFilmanager terms : 8069 MB/s)

you mean KB/second for the filemanager.. 7202 MB/s would be some sort of record
Those speeds are easily fast enough for anything the xbox can stream.

By default xbmc4xbox uses only ram for cache btw. not HD.