# Slow upload speed



## libro22 (Sep 21, 2013)

I got a dedi box in LA a few weeks ago and I notice that it has slow upload speed. 

From an Orlando VPS, it can only seldom hit 1Mb/s. I'm trying to upload from another LA VPS (different datacenter) and highest I can get is 0.7Mb/s. 

Btw, I have 100mbps port. Any tips on diagnosing this issue? 

Thank you.


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## HalfEatenPie (Sep 21, 2013)

First try a traceroute (mtr) to each VPS?


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## wlanboy (Sep 21, 2013)

I use iperf for this type of testing:


+------------------+ +------------------+ 
| Server A +---------------------- + Server B +
+------------------+ +------------------+ 
IP:192.1.1.1 IP:192.2.2.2
iperf server iperf client

And running:


iperf -s -B 192.1.1.1


```
iperf -c 192.2.2.2 -d -t 60 -i 10
```
Parameters:


```
-s : Run in server mode
-B IP : Bind to IP
-c IP : Run in client mode, connecting to IP
-d : Test bidirectional test at the same time
-t 60 : Time in seconds to transmit for (default 10)
-i 10 : Pause n seconds between periodic bandwidth reports
```


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## zim (Sep 21, 2013)

+1 for iperf

As an added note, try playing with you TCP window size. When you are dealing with a long RTT adjusting your window size appropriatly can greatly improve throughput.

http://en.wikipedia.org/wiki/TCP_window_scale_option  -  Explination

http://fasterdata.es.net/host-tuning/linux/  - Tunning

_caveate - _TCP window adjustment will not work with OpenVZ.


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## drmike (Sep 21, 2013)

Typically, I place a file on such a server, behind say Nginx or your favorite web server.  A true random data "speedtest" file.  A 1GB file usually is big enough unless we are testing a very fast upstream.

Testing occurs with wget mainly. 

If single threaded wget doesn't seem speedy enough.   I move over to axel for a multithreaded download instead and compare.

While wonky speeds like this are too common, it is somewhat rare to see in same city/region.  I do traceroutes between the two end points to see which upstreams are involved.

After doing all that, for sanity sake, I compare by testing a speed test file on the same network as my dedicated server.


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## libro22 (Sep 23, 2013)

Traceroutes are normal as verified with provider. We both tried speedtest files, seems to be okay. <= 1Mbps from Orlando and Texas to LA, others go beyond 5Mbps.

Will try iperf and check.


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