Took 15 minutes to copy 25GB over the network

Is this normal, or is my network slow? Any recommendations would be very much appreciated. Thanks in advance.

Our network/shared folders are on 2 separate Windows 2008 servers.
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Ken ButtersConnect With a Mentor Commented:
seems like you are hitting some pretty decent speeds.

see this:

You are faster than LAN 100Mbits/s which would have taken approx 36 Mins.
bobox00Author Commented:
Just to be clear, I am talking about my LAN. The computers are all on the same LAN, in the same building.
Darr247Connect With a Mentor Commented:
25GB = 26,843,545,600 bytes

x 8 = 214,748,364,800 bits / 900 seconds
That works out to about 238.6Mbps, which is decent for normal (1500 byte) frames.

You could probably hit 400-500Mbps with jumbo frames (9000 bytes) instead... i.e. if all the hardware in the path supports jumbo frames; many consumer-grade gigabit switches *don't* support jumbo frames.
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Lee W, MVPConnect With a Mentor Technology and Business Process AdvisorCommented:
To account for overhead, I would recommend thinking of 100 Mbit LAN as 10 MB (8 b(its) = 1 B(yte) but for protocol overhead and other potential issues, best to just divide by 10, not 8).

So 10 MB/sec = 600 MB/minute.
That's 1.2 GB every 2 minutes.
that's about 21 minutes for 15 GB.

And if your disk is fragmented on EITHER side of the copy (and especially both) and if you're copying smaller files or have bad drivers installed on either server OR others are using the server at the same time forcing the disk and network to be split amongst multiple requests, then your SPEEDS ARE FINE - for a 100 Mbit network.  Now a 100 Mbit network is SLOW these days.  Gigabit networks are 10x faster (potentially - still face some of the issues above).  And the Gigabit hardware is pretty cheap.  You DO have to make sure your wiring is AT LEAST Category 5e THROUGHOUT the building (or at least to any device you expect to run at gigabit speeds).
bobox00Author Commented:
When I right-click on my LAN adapter the property page says I'm connected to the LAN at 1GBps. I'm not sure whether most of our wiring is Cat5 or Cat5e (in the walls and such) but I do know that they're not Cat6. I will talk to other people that should have more information about the cabling and report back to you guys. Thanks for all comments so far.
bobox00Author Commented:
At this point, I need to explain to my users that 25GB in 20 minutes is ok for a LAN. If you have any links that I can use to prove my point here, please send them. I greatly appreciate.
Fred MarshallPrincipalCommented:
What that means is that the NIC on your computer is running at 1GBps.  That doesn't mean that links further on in the chain are doing the same.  You need to check them all - at least in the sense of knowing how they are spec'd.  So, if there's a Fast Ethernet (100Mbps) switch somewhere in there - that's the chokepoint from one end to the other (unless there's other traffic being aggregated, etc.).
Gary CaseConnect With a Mentor RetiredCommented:
"... Is this normal, or is my network slow? "  ==>  The answer to this is "It depends" :-)

As already discussed, this works out to ~ 240Mb/s, which is less than half of what you should see on a good Gb network.   but there are several other factors ...

(a)  As already noted, if your infrastructure isn't Cat-5e, that alone explains your speed.   In fact, if you are using Cat-5, that's a very good speed.

(b)  You said "Took 15 minutes to copy 25GB" ==> is that a few large files; or many smaller ones?    You'll get much better speeds with large files, as there's less file system overhead in between the files.   This can make a HUGE difference.    You got a pretty good transfer rate, so I'd assume it was a small number of large files, but just wanted to confirm.

(c)  The total network distance impacts the speed as well.   If your topology involves fairly long runs; intervening switches; etc. that will have a bit of an impact as well.

Bottom line:   While not in the range of a good, all-Cat-6 Gb network;  your speed is actually pretty good.    With some "tweaking" (in both the physical topology and perhaps with the frame sizes) you could probably get a bit more ... but you're doing quite well already.
bobox00Author Commented:
Just trying to be thorough, for the sake of my job and responsibilities. Bear with me. I used LAN Speed Test to check my network speed. Please see attached image and let me know your thoughts. Thanks again.
Lee W, MVPTechnology and Business Process AdvisorCommented:
Perhaps you didn't see my comment?

Factors that impact performance (in no particular order despite numbering):

1. File Size being transferred
2. Network Adapter Drivers (could be an issue on one or both)
3. Disk Fragmentation (could be an issue on one or both)
4. Network utilization at the time of transfer
5. What OTHER services use the same spindles your data is being transferred to/from
6. Packet Size (as others have pointed out)
7. Hard disk type and configuration on EACH server (SSDs?  RAID 10 15K RPM drives?  Single 7200 RPM hard drive?)

There are many factors and if you want to improve performance you need to look at them all.
bobox00Author Commented:
Thanks for your help
bobox00Author Commented:
My apologies for misleading information earlier. I have checked and found that the network cables that run out of our main switches (in the server room) are CAT5e (not Cat5). Our 2 switches are gigabit switches and they are daisy chained.
bobox00Author Commented:
There's a couple patch cables that I see, are Cat 5 (I don't know how many more cables are CAT5 or where they are). If there's a Cat5 cable anywhere in someone's connection path, to a network share, would they be able to download 25GB in 20 minutes?
Gary CaseRetiredCommented:
If there's a Cat-5 cable anywhere in the path, that will be the limiting factor.   25GB in 20 minutes would probably still be possible,  depending on the length of the Cat-5 cable.

As a simple experiment, get a pair of Cat-6 patch cables, and connect a couple PC's to the same Gb switch .... then do your 25GB copy and time it.
bobox00Author Commented:
Yes! Thanks, will try that and let you know
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