gigabit ethernet

[adoo42]

hi guys, need some advice about gigabit switches, probably a vrey simple answer but havent found it yet.

I intend to use a gigabit switch to connect my main pc, my server and the router that connects to other wireless computers and my cable modem. the question is, are gigabit switches capable of running two different speeds as i need to transfer between the main pc and server at gigabit speeds however the wireless router is not capable of gigabit speed. i just need to know that the presence of a 100Mbps device will not bring the speed of all connections down to the same speed.

Any help is appreciated.

[Singh400]

No it shouldn't do at all. I run most of my ports on my GS608UK at gigabit, but one does run at 100Mbps (FastEthernet I think it's called).

[adoo42]

thats great news, thanks!

[Blastuk]

Hang the gigabit switch off your router and then all the devices you require to run at gigabit speeds off that switch (obviously)

If your switch happens to refuse to sync computers at gigabit speeds then disconnect all the connections at the switch then power cycle the switch ..Reconnect all the gigabit capable devices to the switch then connect the router to the switch last(I think that's the order ).. I think this has happened to a few of us on here so just throwing that one out

[Funkstar]

A switch will manage the bandwidth differences between connected clients no problem, that is one of their main functions.

[shaithis]

It is the main thing that differentiates a hub from a switch...and basically why it's called a switch.

The older types (hubs) just broadcast everything they received on one port to all the other ports....thus it forced them all to the same speed (the slowest connection).

Switches intellegently send the data only to the required port, allowing them to negotiate at the highest common speed those 2 ports will allow.

[adoo42]

thanks for your comments guys, have now got it set up and have achieved some much improved speeds however im still falling short of gigabit speeds.

file transfers begin at around 80MBps but quickly fall to around 40MBps within a second or two. if my maths is right "fast ethernet" (100Mbps) would transfer at about 12MBps which was what i used to achieve and gigabit (1000Mbps) should transfer at around 125MBps.

The networking tab correctly indicates that the connection is running at about 30%.

I have set the network controller on both devices to run at 1Gb full duplex and experimented with various jumbo frame sizes. i have also installed the latest drivers for both devices.

anyone any ideas? not really sure what else to try...


thanks

[BUFF]

how fast are your HDDs?

[Agent]

Also is it one large file, or lots of smaller ones?
I find that transferring lots of small files takes significantly longer. It's normally much quicker to rar them up (even with zero compression) transfer that, then decompress.

[Dogers]

Also is it one large file, or lots of smaller ones?
I find that transferring lots of small files takes significantly longer. It's normally much quicker to rar them up (even with zero compression) transfer that, then decompress.

That's due to the filesystem and its overheads of closing, opening and logging all the file changes. One massive archive is always the best way to transfer lots of little files

[Agent]

That's due to the filesystem and its overheads of closing, opening and logging all the file changes. One massive archive is always the best way to transfer lots of little files

It is indeed.

We we're messing about with RAMDrives at work not too long back, and they seem to remove the bottleneck nicely
Not much use for persistent storage though

[adoo42]

thanks for the responses, i never considered that it might be the disk drives but it proably is now iv thought about it. one of the computers has a pair or 10k drives in a raid 0 but the other is an old 2.5" ATA drive. im not really sure what kind of write speeds those drives are capable of...anyone shed a little light on IDE performance?

I was testing with a single 500MB file but thanks for the suggestion.

[xPETEZx]

If the drive is IDE and 2.5", Im guessing its probably a 5400RPM drive. Thats gonna be the killer more than the IDE part.

A 7200RPM IDE drive should provide good performance still.

[stevie lee]

anyone shed a little light on IDE performance?

120GB Hitachi IDE in HD Tach - quick test.



for 5400rpm I would imagine the red line on the graph to be a bit lower down.

[Apex]

I've toped out at 50mb/s over gig and very much doubt i can get anymore out of this rig i have unless i was to raid the lot.....

Other issue is the recieve end able to take in at the speed you dish out....

[Singh400]

I've toped out at 50mb/s over gig and very much doubt i can get anymore out of this rig i have unless i was to raid the lot.....

Other issue is the recieve end able to take in at the speed you dish out....

Think it entirely depends on your setup. When copying stuff across to my WHS box, I reguarly peak at 70ish MB/s, and it's even better with Windows 7 doing the copying now.

Also, depends on how fast your HDDs are on both ends.