Networking speed at work?

[Shaolin_K]

Hi

I'm hoping I can call on experts' help here.

I'm using a decent laptop at work connected to the network by a gigabit ethernet adaptor via USB 3, but when I say copy a file of ~ 500mb from my desktop to a a couple of the network drives, I only achieve a rate of about 40mb / s - is this normal? Are there any settings to speed things up?

There's a program I run which points to the server which can get quite slow, so had it moved to a newer server with updated hardware and runs from SSD, but the performance still isn't great when compared with running it locally.

What are the obvious network bandwidth / throughput settings which might be able to help?

Thanks.

[kalniel]

Each stage will add its overheads - going via a USB adaptor will not be as quick as having a native Ethernet adaptor for example. But otherwise talk to your network/IT guys, there might be other limits in the pathway to ensure that other people on the network aren't affected, firewalls etc. Or they might not be providing you with a gigabit connection! Also it depends what kind of data you're transferring - a single big file might be quicker than smaller chunks. But too large and it may be quicker to chunk.

[DanceswithUnix]

I presume you mean 40 megabyte/sec there, which is 400 megabit/sec so a bit on the low side but not unreasonable.

What sort of program are you running? Some loads need throughput, MB/sec, in which case jumbo frames should help *if* every part of the network you use is configured to allow it.

If you are running something that acts more like a database, then IO per second is your problem, and that is harder (or at least more expensive) to cure.

[malfunction]

Depends on the speed of the drive you're copying from (an SSD in the laptop?) and to (shared infrastructure - actively used by other people at the same time as your file copy?) and what's in the middle (switches, firewalls, etc).

You could try to copy the same data from your internal drive to an external USB3 hard drive or stick to compare, though if there's a mechanical drive involved anywhere (in the local copy) you'll be lucky to get more than 60MB/sec sustained speed.

Also, the theoretical max of gig E is 119.2MB/sec - network speeds are measured in bits (megabits, gigabits per second) using base 10 and the file transfer is probably giving you a transfer speed using MB (megabytes) per second in base 2 - so 40 MB/sec isn't that bad depending upon what you're doing and how often you need to do it.

[shaithis]

As others have said, there are so many variables that the speed your getting is quite reasonable and well within the realm the normal for a gigabit network that is "in use".

The maximum I have ever seen, on a completely quiet segment was 113MB/s which I believe is pretty much the top end once protocol overheads are included (this was with an MTU of 1500, jumbo frames should increase that value)

[abaxas]

Any network manager worth employing would have either QOS or natural contention in place to make it fair for everyone.

[Shaolin_K]

Thanks for the info guys.

Thinking back, I did acheive just under 100 MB/s on a few tests, but maybe that was because the servers weren't accessed by X amount of users?

Will have to mess about with the tcp and adaptor settings.

[DanceswithUnix]

If you got 100MB/sec on a few tests, then there is nothing wrong with your tcp/ip settings.

If the server you are talking to has one or two 1Gb ethernet connection then that is likely the bottleneck as it won't support multiple users.

[Splash]

My gut feeling here is that if your application needs that kind of bandwidth between client and server then it's not a good fit for use across a network - is it something that you could use as a published app instead, reducing the network traffic by keeping the client and server on the same host (or possibly on a network where you could apply QoS between the 2 in order to guarantee the required bandwidth, rather than sending it across a network populated by numerous client OS, and potentially having to negotiate numerous firewalls and routers).

Obviously without more information it's difficult to give any further advice, but my experience is generally the above.

[bledd]

SSD or HDD in your machine?

Don't mess with network settings.