Is there a bandwidth cap on SmartFTP worker threads?

I have access to 15mbps of downstream bandwidth. If I download lots of files simultaneously from the same site, and increase the number of available worker threads in the download queue, I can make use of the full 15mbps. Good. But the bandwidth available for an **individual** queued item seems to top out at around 200Kb/sec. In other words, even if I'm downloading a single file from that server and nothing else is queued, the download speed caps at 200kB/sec. Now, in the midst of that download, I can start a new download of a different file from that SAME server, and that download will run in parallel with the first. Both downloads will operate at 200kB/sec. Any idea why this would be the case? Is there some internal "per thread" bandwidth cap that maxes out at 200? There's a "KBps/Worker" setting which I've tried setting to 0 (default) and also to very high values but it doesn't seem to make a difference.

What's up with that?

There is no transfer limit in SmartFTP but some servers have a per connection limit. That's why using multiple threads/works can improve the overall transfer performance.
You can play around with the performance settings in SmartFTP as described in the article below. But this usually only effective for connection speeds higher than 100mbit/s.
https://www.smartftp.com/support/kb/how- ... f2558.html

Regards,
Mat

Sometimes the limit is caused by the network components and not by the server itself.

Multi Part Downloads are already implemented in the latest version of SmartFTP.

Regards,
Mat

Sometimes the limit is caused by the network components and not by the server itself.

Multi Part Downloads are already implemented in the latest version of SmartFTP.

Regards,
Mat

Thanks. I just discovered the multi-part downloads. By increasing the "Number of Workers/Parts" to a higher number I can download my file at 12mbps -- much better than the 1.6mbps I was getting before. I'm still not sure why this is necessary to spread the download out over so many connections but it works so we'll leave it at that.

Helo,

I'm interested in the same issue Jules pointed out, I searched the options and found the worker/part option in
queued file properties dialog. However, i still need to edit properties of each file i add to queue to increase number
of parts so that my download stream bandwidth is fully utilized. The question is how to set the default threads number
for all future file downloads without having to edit properties each time a file is queued?

Thank you!

I'm having this same issue and came here specifically to see if anyone else was. I have used SmartFTP for years now and with previous versions I was always able to download at the full speed of my Internet connection. Since upgrading to the latest SmartFTP with the worker threads and multiple connections, I'm getting about 1/2 speed when downloading a single file.

My connection is Comcast cable which does around 7mbit, or 900KB/s. When downloading a single file, I'm getting around 450KB/s, about half the speed of my connection. If I download multiple files and set it to 2 threads, I will get about 450KB/s per thread, using my full connection. If I set it to 3 threads, they will go at around 300KB/s, again using my full connection.

I administer the FTP server so I know there are no connection speed limits set and I've looked through the SmartFTP settings to make sure no speed limits were set. I'm pretty sure there is a problem in the SmartFTP download thread code that is causing this. Hopefully you guys will look into this.

Did you do the same transfer tests with another FTP client?

Just downloaded the same file with WS_FTP and I got just under 900KB/s transfer speed, full speed of my connection.

Did you try to change the performance settings as described in this article:
https://www.smartftp.com/support/kb/how- ... f2558.html

Increase the buffer sizes.

BTW: How can you get 900 KBytes/s on a 7 mbit/s connection when the theoretical maximum is 7*1024=700 KBytes/s?

Regards,
Mat

I am experiencing the same problem - i have tried these steps with no solution. I have a 15mbps connection however each single file will download at a maximum ~300kbps. If i download multiple files simultaneously, each additional file will also continue to max at 300 kbps each until all the files have a combined speed of ~15mbps at which they are then running at peak performance. I cannot get any single file to utilize my connections capabilities, this can only be done by downloading multiple files at a max rate of ~300 kbps each

I should mention that i have tried a different FTP program (****Zilla) and it worked at 15 mbps per single file if this may help in determining a problem. seems like a common problem, should this even be a problem to begin with?

still a limit to my dl speed... humm wonder why?

Please post the system information from the menu: Help->About "System Information"

Try to disable [x] Auto Tune Send Buffer Size in the Performance dialog and set the Receive Buffer to 512KB

Regards,
Mat

I'm seeing the same thing. I was downloading prior to installing Smart FTP with FileZilla and I was getting ~315KB/s consistently. Filezilla screwed up the download at the end causing me to lose 1.5 hours of time. So I decided to install SmartFTP, which I use on my laptop and now it only maxs out around 200KB/s.

I currently have two files now downloading and I'm seeing ~300KB/s combined. So there definitely seems to be some issue here.