Sage client network routing

[etk29321]

I've noticed some interesting behavior, and I'm wondering of others are seeing the same thing. The majority of my archived shows reside on a linux raid, and are shared via samba. When I watch an archived show using sage client, I notice that the network path seems to be routing the file from the fileserver, through the sage server, to the client. This means with an HD file I see 20% util on the fileserver and client links, but 40% util on the server link. Is it a bug or a feature that sage client isnt smart enough to leave the server out of the file streaming if the file resides elsewhere? (note, I tried adding my samba share dirs as both mapped drives, and using the UNC paths. Both ways showed the same network traffic.)

I would prefer to record everything to the network fileserver, but I've discovered that watching a HD show live, while recording to a network file server, causes enough network load on the adapter in the sage server to cause jittery file playback. (60+% util). As such, I've had to stick more drive space in my sage server locally, which limits the size of my sage recording drive.

[dagar]

Sounds normal. If your getting that level of utilization, segmentation would be good; 40% utilization on a 100bT segment is very close to the 60% max threshold you want to stay under; normal as in network engineering best practices normal. Back in the 'old days' an Ethernet bus running > than 65-70 could result in a node crash

You could run a seperate NIC from server to server as the simplest cure; or upgrade to GbE -- just avoid running baby giant or jumbo frames because they crap on smaller datagrams (telnet, games, etc). If you do go GbE make sure the switch supports 802.1p (frame pausing; referred to as QoS -- lol) which gives you more tuning options and may make the larger frames doable.

One last thing; you're not running on a hub are you? Hubs are 'of the devil'.

[gplasky]

The server does all the streaming to the client. So if you have your files stored on another box it will always go thru the server.

Gerry

[etk29321]

Ha, nope, switched, full duplex (explicitly set, no auto-neg) 100baseT. I actually think its partially that the cheap NIC that can't cope with 60% util.
Using two NICs is an option, but it would require me to use fancy static routes as I don't want to segment the network. Also, it would increase traffic over the PCI bus. (not that a singe NIC isnt already doing that I'm sure)

But the more basic question is, wouldn't it be much more efficent not to stream everything through the server?

[dagar]

From years of bad experiences I stick with Intel NICs. Anything with 3com on it should be $h*t canned.

What's the datarate on the HD streams? I don't remember off hand. Remember that 100bT Ethernet bus maxes at ~80%. There is 20% or more frame overhead on Ethernet. A 40% load is really a 50% load, etc. That's why the marketing choice was made for GbE to market it as 1000mbs. It's really ~1200mbs per direction (half duplex) but equates to a theoretical maximum goodput (meaning above Layer 1,2 & 3 overhead) is 1000mbs.

If you don't want to segment and/or worry about PCI bus saturation, you should look at GbE. That is if a NIC change doesn't fix it.