• 0

FTP speed limites for single file transfer


Question

simple problem, please assume both parties have sufficient network bandwidth and there is no obvious interference from other applications.

Server is using filezilla server to host a large 17gb file. Client, running filezilla, can only download this file at maximum 50% of their true download bandwidth. Nothing we tried helped this speed.

I split the file into 2 and let the client download both files simultaneously, each file downloads at about 50% max bandwidth which totals to the maximum and everything is peachy...

What's going on here? Why can't the 1 file download as fast as 2 files combined? Server and client have allowed unlimited transfer speeds.

8 answers to this question

Recommended Posts

  • 0

Off the top of my head, there's a setting in either the server configuration or the client configuration setting a maximum speed of 50% of the total bandwidth. Barring that, it's the ISP most likely.

  • 0

I know it's not the server and i doubt it's the clients. They are using default chrome, IE, and even filezilla. I assume the defaults don't have speed maximums per file.

You think it's the client ISPs? anyone aware of comcast or verizon fios limiting per file download limitations on ftp file transfers? <-- seems very unlikely.

  • 0

its not "per file" but per session would be where you would see limits.

Also you sure your tcpwindowsize is correct for your available bandwidth and RTT between this host your downloading from. This would also limit what you could download per session. Creating more sessions would allow for more bandwidth to be seen on your pipe if available.

What OS is your client?

We an get into the math if you want? But lets get some numbers to work with, what is the bandwidth provided by your ISP both up and down? Also what is the ping time to this ftp server?

  • 0

Server is a 100/100 connection. clients are on various connection speeds. 15/5 being the most popular. I am looking for the per session speed limitation options but haven't found it.

Also you sure your tcpwindowsize is correct for your available bandwidth and RTT between this host your downloading from. This would also limit what you could download per session. Creating more sessions would allow for more bandwidth to be seen on your pipe if available.

This makes sense, but I don't know how to adjust the tcpwindowsize. All machines are running windows 7.

Thanks for the tip about the interface speed displays. I think the server shows real time speeds by default so the problem still exists.

  • 0

If you give me the details in a PM, I will see what I can download at.. I have my settings correct - and once can ping server can work out what they should be for max throughput, etc.

PM the details and be happy to test for you.

This topic is now closed to further replies.
  • Posts

    • Password Safe 3.72.0 by Razvan Serea Password Safe is a password database utility. Like many other such products, commercial and otherwise, it stores your passwords in an encrypted file, allowing you to remember only one password (the "safe combination"), instead of all the username/password combinations that you use. Once stored, your user names and passwords are just a few clicks away. Using Password Safe you can organize your passwords using your own customizable references—for example, by user ID, category, web site, or location. You can choose to store all your passwords in a single encrypted master password list (an encrypted password database), or use multiple databases to further organize your passwords (work and home, for example). And with its intuitive interface you will be up and running in minutes. PasswordSafe was originally designed by the renowned security technologist Bruce Schneier and released as a free utility application. Password Safe 3.72.0 changelog: Fixed bugs Improved font scale handling - should resolve font size issues on high resolution displays. GH1749 In the Master Password Setup window, "Show Master Password" is no longer truncated on some displays. GH1092, SF1595 Size and position of main window is now correctly restored on scaled displays. SF1630 Keep password expiry date when both password and password expiry are changed; don't clear a non-recurring expiry when the password's changed. SF1628 Custom values can now be copied to the clipboard in read-only mode via Ctrl-C and right-click->Copy Value. New features GH1196 Dark display mode support: Password Safe now supports the system display mode, as well as setting the mode directly via Manage->Options->Display->Display Mode. This change also updates the general "look & feel" of the app to the current Windows theme. Known limitations: The Date picker and keyboard shortcut controls do not switch to dark theme The Customize Toolbar dialog does not switch to dark theme Custom Field support has been added to the more advanced features: Filters XML and Text import and export Comparison, Sync and Merge databases SF938 Custom field values may now be selected by name and copied via a "Copy Custom Field Value..." submenu in the entry context popup menu. SF936 Notes and Custom fields layout now overlap, selectable by tabs, resulting in a more compact and less cluttered layout. SF935 Autotype: Specifying '\v{name}' in the autotype text will cause the corresponding value to be autotyped. Download: PasswordSafe 64-bit | Portable 64-bit | ~20.0 MB (Open Source) Download: PasswordSafe 32-bit | Portable 32-bit View: PasswordSafe Website | Quickstart Guide | Screenshot Get alerted to all of our Software updates on Twitter at @NeowinSoftware
    • Google DeepMind published a document on June 18, 2026, that may be the most consequential admission yet from a frontier AI lab: alignment training alone cannot guarantee that AI agents will remain under human control, so structural containment must be built before more capable models arrive.............. https://www.techtimes.com/articles/318758/20260620/google-deepmind-ai-control-roadmap-when-alignment-fails-defense-depth-takes-over.htm  
    • I've got a SoundBlasterX G6 that I use in my streaming setup. Sounds great to me and I've had zero issues with the ancient software package so far in Win11. That G6 has 7.1, Dolby, fully working SPDIF and since it's a USB device it's outside of my rig so I don't have to worry about EMF distortion. Looks like for now this is a pass for me as I think I have better hardware....
    • How do you connect 5.1 Speakers to this thing?
    • I agree with both of you... It's absolutely imperative that science is completely based on actual proven facts and hard evidence and is not considered dogmatic in any way. Science is not a religion and it will never be, and that's exactly how it's supposed to be.
  • Recent Achievements

    • Dedicated
      JuvenileDelinquent earned a badge
      Dedicated
    • First Post
      DrWankel earned a badge
      First Post
    • Reacting Well
      DrWankel earned a badge
      Reacting Well
    • Week One Done
      Supreme Spray LV earned a badge
      Week One Done
    • Week One Done
      Genuinetonerink- Dubai earned a badge
      Week One Done
  • Popular Contributors

    1. 1
      +primortal
      502
    2. 2
      +Edouard
      170
    3. 3
      PsYcHoKiLLa
      88
    4. 4
      Steven P.
      75
    5. 5
      Michael Scrip
      73
  • Tell a friend

    Love Neowin? Tell a friend!