Network performance issue

I've downloaded the latest version and my transfert speed from my pc to my network is limited to roughly 70MB/s. Using internet explorer, I can go up to 110MB/s (Basically saturing my 1Gb nic card).

Both pc are running fast SSD drive and I'm used to 110MB/s transfert speed.

Any reason why this slower transfert compared to the explorer one?


How are you measuring the speeds?

Are you copying the same files, and doing multiple runs to account for caching etc.?

Are they a few large files, or hundreds of small files?

I've look at the speed on what's dopus tellement me (in the dialog), as well checking in my windows network ressource and I can see the corelation. Only 70% of my network card is being used.

I'm trying to copy a large file (10GB) file. Caching is not an issue here as both drive are well capable of handling more than what my network switch can handle.

Is SMB 3.X being used behind the scene?

I've also tried the Version 12.0.9 Beta with the same issue. I'm running windows 8.1 x64.

Forgot to mention as well that I've used RAMdisk on both end (both my pc and my nas) to discard any hard drive related issues to to hard drive latency/performance and I could see the same limitation. It seems that I can't go over ~70%. My nas server using windows 2012 R2. If you have two machine running windows, might worth giving it try, considering you have at least a gigabit connection available. I would think it's easily reproducible.

Try changing the copy_buffer_size setting in Preferences / Miscellaneous / Advanced - you might be able to get better results with a larger buffer.

Hey guys,

I tried to play with the buffer size and it did improve, however, I'm still not able to get as good as what my setup is capable. By cranking the buffer size to 100MB, I was able to get roughly 90MB/s (or around 88-92% network utilization), which is a lot better than before but still not getting the full 100%. I'm a bit worry that using a such a high buffer size will have impact on smaller files?

I'm wondering how the windows explorer transfer works behind the scene, what's their logic to determine the buffer size. Which API are you guys using for the file transfer? I'm assuming you need to specify a buffer size in there?

Hey guys,

If you can provide more info on how the transfer gets done behind the scene (ie: which api you guys are using), I can maybe try to do research on my end to see if there are any improvement to make on this one.

In an ideal world, it would be nice to not specified the buffer size and let the algo do it's magic to find the best and fastest way to transfer files. I would be curious to see the performance on a 10GB network link.

let me know if I can provide any help here, I really really like the app but since I'm doing quite a lot of big transfer, performance is quite important for me.

friendly reminder about this one, let me know if I can provide any help.


Is it safe to say that you will not do anything about this issue?

For someone who transfer file regularly, having a 30% drop in performance is not acceptable.

Anywho, I'm sure you guys are swamped with other issues.

Like i said, if I can provide any help to find a solution/test different things, let me know.