In Virtualmin-Backing up Virtual Server via browser limited to 488 KB/s

Hello,

When I back up the virtual server via the browser, it seems the bandwidth only go up to 488 KB/s. I have tested this both via local network and remote location. Same result.

Is Virtualmin restricting/limiting the download bandwidth? If so, how do I lift this limit?

Thanks in advance for your help.

Status: 
Closed (fixed)

Comments

Howdy -- nope! There isn't any form of rate limiting done within Webmin/Virtualmin.

You can see the code for that in "/usr/share/webmin/virtual-server/backup.cgi" beginning on line 151.

Virtualmin creates a temp file containing the backup -- and then begins sending that to the browser as fast as it can.

It's possible that you're just seeing a limitation with files being dynamically sent to a browser, as using tools that do FTP or SCP would be more efficient.

That said -- we can try an experiment.

See line 157 that reads:

while(read(TEMP, $buf, 1024) > 0) {

Try changing that "1024" to instead be, say, "4096", or even "8192".

That will cause it to act in bigger chunks, which could potentially offer a speed difference.

If you make that change, restart Webmin afterwards with "/etc/init.d/webmin restart".

Let us know if you see a difference after making that change.

Per your recommendation, I am using FTP instead. Thanks for your support.

Cool .. closing this ticket then.

Automatically closed -- issue fixed for 2 weeks with no activity.