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What's the point of Gigabit without Jumbo Frames?

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UnclScott

Technical User
Jan 22, 2013
24
US
Let me preface this, as i'm thinking more of the SOHO market. Also, i'm not exactly sure which forum to post this into ~ so if it needs to be moved, please do.

It seems that a vast majority, if not all, Gigabit devices claim, 10 times faster than 100 ~ duh * drools * These include routers, switches, adapters, and hubs. However, the IEEE spec doesn't include jumbo frames.

On nearly every device i can think of, in a Windows environment, when you send or receive, you max out at 100Mbs ~ 10% usage. By design in Windows, the native WHQL drivers ( or those on a Disc ) do not support jumbo frames. You have to tweak settings, which may or may not get you to the 100Mbs limit ( typically you'll be going at 5% ). Moreover, a switch or router usually has gigabit across 4-5 ports, or 200-250 Mbs per slot.

Honestly, my home network is nutz trying to achieve max rates between devices. The Internet isn't much an issue, as it's controlled and limited by my ISP. Here or there a download to a common location, but usually less than 20MB, and then used by multiple systems; DLNA is a great thing.

So i have a modem, to a router, to switches for wi-fi ( cell phone, printer, friends tablet's and laptops ), Fast ( VOIP, Blu-Ray, my non-jumbo frame devices, Xbox ), and Jumbo ( NAS, a few pcs ). I've spent a fair amount of time trying to optimize my home network for speed. I deal with a lot of video files and editing. The files are on my network ( as are backups ), so my network speed is really critical.

I guess what i'm asking is, is it really fair to claim 10 times faster than Fast, if you really are only getting Fast speeds? It's like buying a car that has a Speedometer that goes to 100mph, but only lets you drive at 10 mph, after you tweak things, but 5mph normally. Just how are people supposed to get to even 50% usage? How does the common Gigabit device really improve performance without Jumbo Frames?
 
i guess with 1000Mbit on my home network (little HP 1410 - 16G) I get around 20MB/Sec transfer to my NAS and I on 100Mbit I would get around 10MB/Sec copying to my NAS.

If it doubles my speed at home, Im happy. If at a customers site on £2000 switches it did that, I would be pissed!

see where I am going with this?

ACSS - SME
General Geek

 
Still that's only twice as fast. To test things out, i'm using Lan Speed Test by Totu Soft.
[URL unfurl="true"]http://www.totusoft.com/lanspeed.html[/url]

I enter in a location on my NAS, set the test size to 1250 MB - This is what i get:
Version 1.3.0
OS Version: Windows 8
Date: 07/21/2013
Time: 15:30:57
Program Parameters: 0
High Performance Timer: 0.0000005133

Test File: \\<server>\<fldr>\lanspeedtest\NW_SpeedTest.dat
Write Time = 134.8583536 Seconds
Write Speed = 74.1518800 Mbps
Write Bytes per second: 9,268,985
Read Time = 124.9791423 Seconds
Read Speed = 80.0133520 Mbps
Read Bytes per second: 10,001,669

No where close to the the 119 MB/s Max.
 
Well, perhaps a poor example as writing to my NAS in RAID 5 might not give a particularly great amount of performance.

ACSS - SME
General Geek

 
It seems that a vast majority, if not all, Gigabit devices claim, 10 times faster than 100 ~ duh * drools * These include routers, switches, adapters
Welcome to the world of ignorant marketing people aka liars.
There are loads of things affecting the perfomace.
1. The hardware it's attached to. If your NAS was rammed full of SSD's, you'd see a huge leap (and in cost as well). Also some NIC's are much better that others, the one bundled with your PC is most likely to be pretty basic and have anverage drivers. Search for Gamer network cards.
2. Cabling. Cat5e is good enough, Cat6 better. Shorter the cable, the better.
3. Backplane, the massivly overlooked one. If you have 10xGb ports, what's the backplane, i.e. the glue that sticks it together? Very often this is nowwhere good enough (even on a certain well know pro brand). It's all well having 10x1gb but if the backplane is 5gb, that's you limit across the lot. Some have mulitpl backplanes, but the limits still apply.
4. Traffic management. This is when the above issues cause issue on the network and retransmits are required. The faster the speed, and the more congestion, the more retransmits.

Robert Wilensky:
We've all heard that a million monkeys banging on a million typewriters will eventually reproduce the entire works of Shakespeare. Now, thanks to the Internet, we know this is not true.

 
I put some HP Procurve switches into a site not too long ago connecting 2 x HP DL360 Gen8 with 10Gbit SPF+ copper, with a Synology RS3412XS-10G (10Gbit SPF+ interconnect) and 10x 1TB WD 10K Raptor SATA drives bound with an HP 2910-24G with 10Gbit SPF+ modules. This was for ESXi - and it works superbly.

Not bad switches for the price. 128Gbit switch capacity.

Doesn't really compare to home networking, but this is still only mid range kit, and the switch alone with the SPF+ modules cost £2200

ACSS - SME
General Geek

 
Sorry for the delay, work came up and all :s My NAS is 4 SATA RAID5. Not the fastest thing around, but at least i can go as fast as external USB 2.0 drives; if i do a bunch of smaller files ( less than 500 MB ) i go a lot faster. I should note, in the Lan Speed Test, i'm pretty sure it doesn't count the overhead for frames and such, but even adding in the extra MB's, it isn't close. i digress...

I do feel this is more of a marketing lie. The standard is Gigabit, but it doesn't really mean 10 times the performance for most people/businesses. Somewhere, i'm wondering, what is the cheapest possible set up to get close to the 10 times performance? Or even, let's say at least, in real world situations, say 30 MB/s.

Maybe there should be a note stating, typical performance increase of 1.25 - 1.5, maybe 2. Or some better instructions/drivers/installers that would actually tune performance based on CPUs and their Cores, Windows/Linux/Samba installations. Perhaps even a note stating, contract your local IT professional to tune your network performance.

Yes i've got a 7.1 Onkyo Surround Sound system, but oh, it's connected to a dial tuning, solid state, AM radio.
 
@strongm - I figured Lan Speed Test ( LST ) was free and people could post their results if they were interested in checking their networks. It's ball park, and the full version costs $6 USD.

I think somewhere i saw a 50 MB/s a few times, but i can't remember my file size :\ The 1250 MB came about because LST uses 10^6 for M, and i can never remember 1343 ( about 1.25 GB ).

Oh ya, and ty for the link :)
 
So one of the problems with jumbo frames is that you might increase latency depending on how much traffic you're actually pushing through. For instance, if your frames are less than 9000 it is possible for your network to build your frames to 9000 before releasing them. Where if they were 1500 you could get a faster frame rate. Honestly I don't think this is much of an issue with gigabit networks as opposed to 10 gig networks but it could still be an issue.

If you're not slamming your network, you could just be increasing your latency by adding jumbo frames.

The answer is always "PEBKAC!
 
I can appreciate that ~ and i do hear you. However, i think most transfers, home, home office, small biz, ( workgroups + a few ) would benefit from Frames. We're moving towards NAS and cloud storage. Cell phones take pics the size of mp3s, DLNA is becoming more and more integrated, backups of system images, and WordPress websites... I think most people don't give their back end a second thought.

But still, shouldn't the transfer of a GigE network be on par with a Class 10 SD card? What about USB 2.0? I think what is getting to me is all the claims of 10 times faster, of a speed increase. There is something wrong out there
 
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