The Old Joel on Software Forum: Part 4 (of 5)

Gigabit Ethernet?

I have a home network with about half a dozen machines, networked with 10/100 Ethernet. I'm thinking about Gigabit Ethernet, and wondering:

1. Is it worth it to spend a few hundred bucks and upgrade? Will I see a dramatic speed increase, or just a modest one? I stream MP3s and video, I don't just surf the Web.

2. Do people have specific manufacturer recommendations? I run primarily Linux with a few Windows machines.

Thanks in advance.

Sharkbait
Tuesday, February 3, 2004

Yes.

That is all.

.
Tuesday, February 3, 2004

You will see very little benefit from gigabit ethernet. If you're downloading data from the internet (web pages, streaming media, etc) your choke point is your broadband connection. E.g., a typical DSL or cable modem connection has a download speed of around 1 or 2 Mbps. Even a 10 Mbps ethernet connection can handle this easily -- getting a faster ethernet connection won't offer any improvement.

The only benefit you'd see with gigabit ethernet is when transferring large files between computers in your house. If you do that a lot and you have money to burn, go for it -- but generally, gigabit ethernet is overkill for home networks.

Robert Jacobson
Tuesday, February 3, 2004

Unless you've got a *really* fat pipe, it's not going to help you one bit with anything that must go over the uplink from your house.

If both endpoints on your streams, etc, are within your house, then it might matter.... you should be able to calculate roughly how much bandwidth you're using and how much you need.

Do you currently notice that you don't have enough bandwidth? More than likely 100baseT is plenty...

Michael Kale
Tuesday, February 3, 2004

if somebody has 6 computers at home in a network, well, he probably do not use a 14.4Kbits modem for downloading, so i assume the speed is for his inter-computer connection.

first, check if your network is 100% loaded when you play a streaming video.

maybe it's only 50% because you network card, operating system or hardware is not speedy enough.

Tuesday, February 3, 2004

When I transfer files between my computers on my regular connection it goes faster than creating a copy on my own hard drive - the drive's speed seems to be the limitation.

Unless you're talking about dozens of computers sending lots of data across only your network, I don't see the benefit.

www.MarkTAW.com
Tuesday, February 3, 2004

At full utilization, you're talking about approximately 100 Megabytes a second. Short of a RAID array, you'll never get data off the disk fast enough to make good use of that.

Also most consumer-grade operating systems and computers won't be able to make full use of the Gigabit ethernet bandwidth. You'll probably be lucky to see twice the throughput you get on 100 Mbit ethernet.

Speaking of which, you might want to do a little benchmarking of your actual point-to-point throughput on your network. Efficient network drivers and boards will make a big impact. Make sure your switch supports full-duplex mode (assuming you've got 100BaseT now).

-Mark

Mark Bessey
Tuesday, February 3, 2004

Let's also not forget that the PCI bus is nowhere near 1 gigabit in bandwidth (and it's shared), so this is not really an "upgrade" friendly item (unless what you're upgrading is your motherboards, to one of the ones that has a new, ultra-fast bus dedicated to the gigabit ethernet).

And, oh yeah, if you're pulling data from disk, as others have noted, forget about it. You'll never saturate it with disks that are lucky to burst around 100Mbit until the cache is depleted, and then buzz along at 30-50Mbit. If you're lucky.

Brad Wilson (dotnetguy.techieswithcats.com)
Tuesday, February 3, 2004

> The only benefit you'd see with gigabit ethernet is when transferring large files between computers in your house.

Yep, that's my situation exactly.

> You'll probably be lucky to see twice the throughput you get on 100 Mbit ethernet.

That doesn't sound so bad.

The prices I'm seeing for the equipment are about $120 to $150 for the Gigabit hub, and roughly $40 per network card. Does that sound about right?

> Speaking of which, you might want to do a little benchmarking of your actual point-to-point throughput on your network.

Any references to point me to?

Thanks again everyone.

Sharkbait
Tuesday, February 3, 2004

PCI? Why would you pick machines from a vendor that'd put the Gig-E in a legacy PCI backwater? Yuck.

Gig-E is mainstream today. Go for it, and post back to gloat.

veal
Wednesday, February 4, 2004

> The prices I'm seeing for the equipment are about $120 to
> $150 for the Gigabit hub, and roughly $40 per network
> card. Does that sound about right?

Reasonable for a low-end card, I guess. I wouldn't bet on getting anything like the rated output on those cards, though. I can't find any good benchmarks of different cards with a quick google search, maybe someone else knows of a good comparison online.

If it's possible for you to do so, check into 64-bit PCI cards. They *should* have better throughput.

>> you might want to do a little benchmarking of your actual
>> point-to-point throughput on your network.
>
> Any references to point me to?

I've used netperf for this sort of thing before ( http://www.netperf.org ). But really, any protocol with low overhead can be used for a simple stopwatch test.

Copy a 1GB file between any two nodes on the network, and time it. Should take about 2 minutes with 100BaseT, and much less time with Gig-E.

This is where network driver performance and OS tuning come in, though. Some systems just can't push packets faster than a certain rate.

-Mark

Mark Bessey
Wednesday, February 4, 2004

I don't really have anything to add. I think now days at least 70% of the power users with 2+ computers at home should seriously consider gigabit frameworks in their apartment or homes. Upgrade for all the patch panels (USD$40-100), wiring and jacks (USD$4-15 per line) doesn't have to be unreasonable (as long as you say away from Home Depot and friends, where they overcharge for these bits of hardware)

I am not much of a power user and already in my house we do the following:

* Burning CDs on the wrong computer (ex: you rip it on a machine without CDR drives, so you have to transfer all the files to the other machine).

* Record TV, play back streamable TV and MPEG4 files.

* Play games.

* Check email.

Most the time if our machine acts unresponsive it's due to large file transfers. Although bottleneck is mostly hard drives, it doesn't mean you shouldn't upgrade the network. You still want to upgrade the network if you can shave off hours of file transfer time between machines (between the DVD backups and the jukebox for example). Most of us don't have all evening to wait for such a process when there's better things to do and with time this will only get worst.

Li-fan Chen
Wednesday, February 4, 2004

Six machines? Why?

I can see one as router etc., one as local mail server perhaps, and one as client machine, but... SIX?!?

Wednesday, February 4, 2004

> Six machines? Why?

Windows desktop, Linux desktop, my laptop, wife's laptop, network server, file server, backup server and a Windows machine for the kids.

Q about 64-bit cards: would I need a 64-bit CPU and 64-bit OS to take advantage of the 64 bit card?

Sharkbait
Wednesday, February 4, 2004

64bit PCI devices doesn't necessarily means computational instructions from your software.

The elemental computational instructions your MS Word uses are commands like ADD DELETE MODULUS, etc, the word width of the chip that crunches this thing (AMD Intel) is the width of the number you can deal with. So on Pentinum4 and older you'll be able to deal with any number smaller than 2^32. The bus and bits on PCI are exclusively the domains of the PCI controller, who translates driver instructions to paint on a printer or read from a network card to PCI instructions going to the PCI card. These words can be a set width, like 8 bytes, and multiple blocks of 8 bytes may be shuttled in one cycle if you can take that efficiency route by expanding the bus.

Li-fan Chen
Wednesday, February 4, 2004

I meant 8 bits

Li-fan Chen
Wednesday, February 4, 2004

From experience: Windows 95/98/Me will be a bigger bottleneck than any network connection upgrade. If you're running any of the above, you'll have performance problems with streaming video if either the source or target machine is running the above OS's. I had, at one point, a dual-boot 98/2000 machine, so this is not just idle speculation--I tested this at one point.

pds
Wednesday, February 4, 2004

How are you sharing these files? If you are using Windows file share, you will see a huge improvement just by switching to different software. In my experience, copying between two windows shares is horrendously slow and comes nowhere near saturating 100baseT

MikeMcNertney
Wednesday, February 4, 2004

Dear Mike,
In my experience it depends what you are copying. If it's just one large file, then you will get near maximum speed. It gets slow when you are transferring lots of small files.

Stephen Jones
Friday, February 6, 2004