Network speed limit to 200 Mbits/s for backup ?

[simssototo]

Hi Support,

I'am using Backup4all Professional V.6.1 build 188 on Windows 10, and it's a great product, but I experience a problem when I backup to a NAS.

I noticed that all my backups to a NAS are quite slow, and never exceded 200 Mbits/s. My network is full Gigabit.

I did some tests to isolate the problem.

1/
I transfer a 4,5 GB file using Windows Explorer to the NAS and the transfer speed is about 950 Mbits/s (110 MB/s). So the network speed and the disks array speed in the NAS can't be the source of the problem.

2/
I create a new backup job (full backup) for this only file, without compression or encryption to try to maximize speed.
The result are in the following screenshots.

Task Manager when backuping to NAS ("Envoyer" means upload) : http://img4.hostingpics.net/pics/382424Capture.png

Task Manager when testing backup ("Recevoir" means download : http://img4.hostingpics.net/pics/286236Capture3.png

The upload speed never exceed 200 Mbits/s. Moreover, when Backup4all test the file once copied, the network read speed is a slitly over 200 Mbits/s.

3/
To verify that the source hard drive was not the problem, I repeat the same procedure with a RamDisk indead of my data hard drive.
The result is the same than the test 2/.


I contact you because I can't go any further to resolve this issue.
Can I send the logs of those backups directly by email (support[at]backup4all[dot]com), or need I a ticket number ?

Best regards
Jonathan

[Adrian (Softland)]

Hi,

Please send us the logs to support[at]backup4all[dot]com. Also specify about the forum post to know about it.

[Xyzzy]

Fast forward 4 years and I have an identical issue.
I've already sent a message to support.

[Adrian (Softland)]

Hi,

We will investigate the situation.

[Xyzzy]

So eventually I investigated the problem (as it appears B4a is NOT tested with such exotic servers as Samba - so buyers beware) and so far discovered, that it uses varying send buffer size 1 or 4 MB, with Windows default being 512 kB - improper buffer size is often reason for such problems.
I've requested some modified version to test it (building from a release branch with one constant inserted should be simple in well maintained code, right?) and waiting...

By the way, 200 Mb/s was the best case, with smaller files the transfer is well below 100 Mb/s.

[Xyzzy]

Unfortunately just the buffer size is not the cause for the issue. I got a test version from support and tried values ranging from 32 kB to 128 MB. The most I could get was about 230 Mb/s.
I also tried to use a third-party file manager in addition to Windows Explorer, and it reached the same speed as Windows Explorer - over 900 Mb/s.

[Xyzzy]

The speed is fixed in v8.9 - now it's roughly the same as when using other software.