Recieving duplicate WUs from 171.65.103.160

[Flathead74]

I have been inspecting my Fahlogs because it seems that I am missing credit for several WUs, at 2435 pts each.
Considering the WUs in question, this amounts to quite a bit of (wasted) work.

At present, I have several Uni-processor clients running on several different machines.
Naturally, all have their own unique identity.

I have just completed and uploaded Project: 2446 (Run 22, Clone 28, Gen 0),
for system with User ID: 6C56DD134EE52930, Machine ID: 1.
This was downloaded: [12:32:51] Working on queue slot 06 [April 18 12:32:51 UTC]

But wait, on system with User ID: 11D024D827DB11BF, Machine ID: 1,
I am also processing Project: 2446 (Run 22, Clone 28, Gen 0), downloaded, [10:11:58] [April 18 10:11:58 UTC].
This WU is at 68% completion at this time.

I have checked the Registry Keys in both systems and they are different from each other.

This is not the first time I noticed this, as it also appeared to be happening a few days ago when
I inquired about the server for these WUs being down.
I just figured it was a one time thing and didn't mention it though.

Any ideas?

[bruce]

When a WU is not returned by the Preferred Deadline, it is assumed to be lost and a duplicate is issued. With a combonation of expired WUs and EUE, it's possible for multiple WUs to be in circulation. In these cases, all copies returned before the final deadline will receive credit.

If you're sneakernetting or otherwise moving WUs or manipulating the queue for any single UserID/MachineID, you may be assigned duplicate WUs, but these are different in the sense that you only get credit for one of them.

[Pette Broad]

I've seen many, many duplicates even triplicates and more over the years. I've never found a way to avoid them but there is an easy way to find duplicates to save wasting in some cases days of CPU time. I use a montoring utility called FAHSpy which spots any duplicates and highlights the Run/Clone/Gen in Red. Don't know if FAHMon has this capability, haven't used it since I discoved FAHSpy. Once you've spotted a duplicate you can then safely delete one of them. The only slight problem is that you may get the same unit again (and again) so on occasions I've found that I have to change flags/settings temporarily to get alternative WU's.

In these cases, all copies returned before the final deadline will receive credit.

Hadn't realized this...does it still apply if for example a dual core picks up the same unit? I've seen this happen a few times when I startup a machine and both the units are downloaded within seconds of each other...


Pete

[bruce]

When two clients download the same WU at the "same" time, both WUs are valid (as long as the two clients have different UserID/MachineID settings). When you fail to return a WU and the server reassigns it to you -- either because you're sneakernetting and you've moved the WU somewhere else, or because a FahCore error causes the WU to be deleted without creating a file to be uploaded, then the WUs really are duplicates and you'll only get credit for one of them.

[Flathead74]

Thanks Pette.
Fahmon doesn't have that capability.

Bruce, I still don't understand why I received the same WU twice, within a span of 2 hours 21 minutes.

Why would the server think that a WU with a 42 day Preferred Deadline would be lost within a span of 2 hours 21 minutes?

[bruce]

Why would the server think that a WU with a 42 day Preferred Deadline would be lost within a span of 2 hours 21 minutes?

Without a detailed map of how many times a WU had been distributed and the number of EUEs or deadline-violations that might have happened before you received the WU you can't really say how two copies got separated by 2:21. (That information is invisible to me, too, so I can only guess.)

[Pette Broad]

When two clients download the same WU at the "same" time, both WUs are valid (as long as the two clients have different UserID/MachineID settings).

O.K, Thanks for the information


Pete