Problems with Background Transfer Manager

[MichelPy]

Since version 6.0x the Background transfer manager can control speed of copied/moved files (thanks to my blind obstination and the coding merit of Mr. Ghisler) !

I use it extensively and I love it ! Thanks A LOT !

I have found two frequent Problems/Bugs with the current implementation :

1. When I activate/deactivate more than 2 times the speed limit checkbox, the background transfer manager often aborts the current transfer from itself some times later (at the end of the currently copied file I think) !

2. Only on some Win2000 PCs (but not all), the speed limiter does not limit speed at all. The speed limit value I set is totaly ignored and the full bandwidth is used. Even the speed display is correct (limit = 100k, speed = 997k for example). On the WindowsXP PCs I have the speed limiter always works...

Am I alone experiencing this ?
Could someone try to reproduce my problems ?

Thanks in advance.

[ghisler(Author)]

1. When I activate/deactivate more than 2 times the speed limit checkbox, the background transfer manager often aborts the current transfer from itself some times later (at the end of the currently copied file I think) !

Is this with FTP connections? Some FTP servers may drop the connection when no data is transferred for some time.

2. Only on some Win2000 PCs (but not all), the speed limiter does not limit speed at all. The speed limit value I set is totaly ignored and the full bandwidth is used. Even the speed display is correct (limit = 100k, speed = 997k for example). On the WindowsXP PCs I have the speed limiter always works...

For what file operations? For copying, speed limit was added only in TC 6.0 and later.

[MichelPy]

Is this with FTP connections? Some FTP servers may drop the connection when no data is transferred for some time.

no, only with file moves or copy locally (C -> D) and on a LAN (10Mbps).
If I don't touch the "speed limit" checkbox, everything always runs fine .

If I switch the "speed limit" on and off more that 2 times, then the transfers almost always stops some times later (as if I had clicked on the X on the title bar of the BTM)

For what file operations? For copying, speed limit was added only in TC 6.0 and later.

for file copy and moves (TC 6.x only) !
If you remember well I was the one who asked you for this option in August 2003 !
Previously I asked for the Pause and the FTP speed limit, but who cares today...

It works very well on XP Machines, but seems to "don't care" on some Windows 2000 PCs.
On these Win2k PCs (this is always the case) TC copies/moves at full speed even if the "Speed limit" checkbox is checked !
The kB/s value stays at approx. 950 kB/s without caring at the Limit I define (mostly between 50 - 500 kB/s)

It doesn't matter if the files are copied/moved locally on via the Lan.
It doesn't matter if I pause/restart the transfer
It doesn't matter if if deactive/reactivate the speed limit
I made tests with TC cache buffers enabled or disabled. I saw no difference.

[ghisler(Author)]

If I switch the "speed limit" on and off more that 2 times, then the transfers almost always stops some times later (as if I had clicked on the X on the title bar of the BTM)

I switched it on+off 20 times but the copying never stopped. I tried this with all 3 copy modes (small buffers, large buffers, and compatibility mode). Maybe it has similar reasons as the aborting described by another user who uses a multiple desktop software?

It works very well on XP Machines, but seems to "don't care" on some Windows 2000 PCs.

Is there a configuration difference (in TC) between those where it works and those where it doesn't work?

[MichelPy]

Only on some Win2000 PCs (but not all), the speed limiter does not limit speed at all. The speed limit value I set is totaly ignored and the full bandwidth is used. Even the speed display is correct (limit = 100k, speed = 997k for example). On the WindowsXP PCs I have the speed limiter always works...

between my citation and today what I can say is that the speed limiter works randomly. It is not machine dependant.

I used it approx 500 times since version 6.0 of TC. I used every other version of TC since (-> 6.03a) without change.
40% of the time it works well ! (I love it !)
55% of the time it doesn' t limit the transfer speed (it works at full speed or at the max available speed)
5% of the time I'm able to convince it to limit transfer speed after pausing the BTM and starting it again (not always sadly)

I speek of file transfers using the BTM (copy or move) on local disks, via the network (10Mbps) or from local disk to USB disk.

What is really strange is that the speed display is absolutely correct (997k for example), and this doesn't hurt TC to continue to copy at full speed even when the speed limiter is activated...

The other demotivating thing is that sometimes the speed limiter works for a first BTM use. And when I start the next transfer with the BTM on the same machine it does not limit the speed anymore...

I can organise a demo via VNC for Mr. Ghisler if needed !
I could make a little AVI film too

[ghisler(Author)]

I think that I have found the reason why this happens - I will try to find a workaround in the next release of TC. It seems that the speed limit function is not called in some cases due to an optimization (calculate the speed only every 100 ms or so).

[MichelPy]

sometimes at the beginning of the transfer the transfer speed is not refreshed. after pausing and starting the BTM the display is alive and refreshed very often.

I can assure you that the current speed calculation is perfectly correct. On our 10Mbps coax network I get near 1000k, value moving +/- 10, refreshing every seconds or so, less when I steal bandwidth with some other transfer elsewhere.

but the problem is that the speed limit I set is sometimes totally ignored !

TC compares perhaps the speed limit with the something else as the displayed current speed (or as you said doesn't compare anything at all sometimes)...

[lukval]

I think that the background transfer manager in version 8.51 x64 cannot control speed of locally copied/moved files too.
When trying to limit the speed to 1 kB/s, displayed speed is approx. 4 645 kbytes/s. Without limitation it's displaying approx. 75 142 kbytes/s.
It doesn't matter if I pause/restart the transfer.
It doesn't matter if if deactive/reactivate the speed limit.