# Reasonable wired transfer speeds

## machinelou

I'm trying to transfer large files from a linux box running gentoo to a windows machine over ssh.  The machines are connected across a Linksys wrt running open wrt.  Using WinSCP, I see max transfer rates of about "CPS: 1,900 KB/s".   It seems kinda slow for a wired connection, or does it?  If it is low, what can I do to troubleshoot the problem?

ethtool on the gentoo machine:

 *Quote:*   

> Settings for eth0:
> 
>         Supported ports: [ TP MII ]
> 
>         Supported link modes:   10baseT/Half 10baseT/Full
> ...

 

If I'm reading this right, the disk on the sending machine doesn't appear to be the bottleneck.

 *Quote:*   

> hdparm -t /dev/sda1
> 
> /dev/sda1:
> 
>  Timing buffered disk reads:   90 MB in  3.03 seconds =  29.75 MB/sec
> ...

 

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## barophobia

TCP overhead, delay in acking packets, processing data.  All this adds up.  Plus winscp needs to decrypt and write to disk.

1.9MB/s seems to be a good number for winscp if I remember correctly.

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## bunder

does winscp have a speed limiter?  perhaps its set low by default...

cheers

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## syscrash

For some reason transfers involving windows machines have always been slow for me, but using good old scp on the same connection gives me

```
% ls -alh gt-hd_paris.wmv 

-rw-r--r-- 1 syscrash syscrash 54M 2006-09-28 17:57 gt-hd_paris.wmv

% time scp gt-hd_paris.wmv sigma:/tmp/ 

gt-hd_paris.wmv                                   100%   53MB  10.7MB/s   00:05    

scp gt-hd_paris.wmv sigma:/tmp/  0.86s user 0.41s system 23% cpu 5.297 total
```

That somehow amounts to an average of 10.19MB/s. This is a 100mbit connection using CAT6.

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## Cyker

 *syscrash wrote:*   

> For some reason transfers involving windows machines have always been slow for me, but using good old scp on the same connection gives me
> 
> ```
> % ls -alh gt-hd_paris.wmv 
> 
> ...

 

Impressive - That's roughly the theoretical maximum for a 100BaseTX!  :Mr. Green: 

I get about 15MB/s sustained and 40MB/s burst on my GigE line  :Sad: 

Although this is with CAT5e... Although now I wonder if CAT6 makes much difference...?

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## sf_alpha

Nothing with CAT6. CAT5e is enough for most LAN even Gigabit if distance is less than 30Metre.

Windows machine may be the problems especially if you have some antivirus or firewall software.

If your machine is old, may be you have problems with CPU overhead for encryption.

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## machinelou

CAT6, CAT5e? Is that just the specification for the cable?  Or, do you need special hardware?

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## barophobia

Using winscp 2500 KB/s ish.  computers separated by one switch.

Same setup using linux. 11 MB/s

Conclusion: windows is just slow.

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## Monkeh

 *barophobia wrote:*   

> Using winscp 2500 KB/s ish.  computers separated by one switch.
> 
> Same setup using linux. 11 MB/s
> 
> Conclusion: windows is just slow.

 

Correction: WinSCP is not efficient.

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## machinelou

I just tried putty's release of scp and got max speeds of 2500 KB/s, so maybe it is windows... Just another data point.

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## Monkeh

 *machinelou wrote:*   

> I just tried putty's release of scp and got max speeds of 2500 KB/s, so maybe it is windows... Just another data point.

 

No, it's WinSCP.

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