MT5 forward testing bugs.

This post is about a some weirdly related (I think) bugs that happen when forward testing optimized results. Please read through it all.

The first bug is that the displayed results from the top section of backtesting passes in forward tab are wrong. (Highest scoring passes in the backtest category, in the forward results tab) You can see this if you double click a pass in the forward results tab to run it in a single test, the resulting profits/trades will be different. The first two images give an example of this. The first is the listed profit/trades/ect seen in the forward results tab, the second is the (real) results for running the same pass in a single test. I don't know how many of the top passes this affects, it seems to vary on each run of the ea. (One that I have pulled up here doesn't have real results until a couple thousand) I also can't find out exactly where the incorrect passes stop for this reason: The shown result for most of the top is equal to the real result in a single test. So I also don't know if every pass up to a certain point is wrong (and the ones that actually do match, only match because they have the data from another pass that has the same result) or if only the outliers that sporadically appear are wrong. I am not wording this well so I am going to try to draw it out:

(1,1,5,1,1,1,5,1,1,1,5,1,1,5,1,1,1,1,1,5,1,1,1,1,1,5)  Shown result.

(1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,5,1,1,1,1,1,5) Real results from single testing.

                                            |here?|here?                Where do the bad passes end?

       5          5          5       5                                      Are just the 5's bad?

 1,1,5,1,1,1,5,1,1,1,5,1,1,5,1,1,1                             Or is this whole section bad?                                                                                                                                                                                                                           

This is just a really annoying bug because you see good forward passes in the top section for the optimization passes but it's just a visual bug and they are actually terrible.

The second bug happens during the first 512 passes in the forward testing. For the first 512 passes the agents/cores are assigned and complete way more passes than 512. For example say there are 10 cores that are each be assigned 1000 passes to complete. When they are all done only 512 passes will have been added to the final amount. You can see many passes being completed by each of the cores but they do not get counted towards the total. Instead the total number will go up to 512 seemingly separate from what is done by the cores. (It also starts out fast and slows down as if cores are finishing their section and only a couple cores are still calculating (like what you see in normal passes)). If this bug were alone I would think that that is just the way it does forward testing, but the number 512 comes up again and it might be doing something weird with the excess passes that messes something else up. This can be seen in the third picture, the seemingly arbitrary total number of passes got to 512 but the cores are still chugging away at the excess passes they were assigned. (they started around 4000 because the amount carries over from the optimization (but still most of them were assigned 1600))

The third bug happens from 512-1024. It does the same thing that 0-512 does (it is assigned and completes more passes than what it should). But this time it runs it on passes that should be on the end of the results. I don't really know how to word this so look at image 4. In the graph view you can see a chunk of passes that belong to the end, are tested at the start (at 512). Is this part of the reason why the first 512 passes are wrong? (bug 1) I don't know but this is another 512 chunk of passes that are weird.

I don't know exactly when but somewhere at the start (around 512-1024) the journal tab gives an error "x forward passes not processed and returned to task queue"

The passes from 1024 to 65536 work as you would expect. Each pass a core does corresponds to a pass being counted to the final result.

The fourth bug is that after 65536 passes (again very specific and this one I am less sure why its that number) It will just start failing passes (for lack of a better term). Up to that point you can see the results of passes vary throughout the graph as it does each one. But at 65536 passes it just flatlines, every result is the same as it keeps failing over and over. I say fail because you can see lots of passes being completed by the cores but the 65536 number will not go up. In the journal it keeps repeating "x forward passes not processed and returned to task queue" the number that it says doesn't seem to be significant, its not a random power of two and it changes on each rerun of the optimizations. (its 10753 for the one I'm doing right now). If you stop the test while its stuck on 65536 the whole program will freeze and never unfreezes. I have left it for hours to unfreeze but I just end up having to close the program in task manager because it never does. What is unfortunate is that when I close it with task manager sometimes the forward results tab disappear on reopen. I have had to redo hundreds of hours of calculation to the results disappearing like this. Another user has posted about this in forum post 424890. I don't know if this is another bug or not. You can see it get stuck in image 5. Some random maybe helpful info: In a forward test I did the total number of passes it needed to calculate was 75,000 most of the cores were finished as it neared 65536 (some were faster than others) It stopped at 65536 per usual but instead of the other cores finishing what they had left (and getting to 75,000) they all got assigned more tasks to do for whatever reason.

Its been so long sense I let one get to 65536 I don't remember if it actually finishes, I usually stop them right before. I have one running right now that I did let get there, it is at 65,536/75,000 passes but the chart shows that the total passes of failed + unfailed is at 85,000 and it will keep going up. I don't know if it will ever finish, I'll give it a little longer but man I hate wasting hours just to document what happens. I'll post later if it finishes or it finishes me.

This has happened with many different EAs. All my EA's are variations of the generated expert advisor template. I don't really want to post the code (I like to think my code is good and I'm special and I didn't just copy others) but I think this is replicable by just running an EA with the fast genetic based algorithm with lots of inputs. To see the last bug you need enough inputs that it does ~100,000 passes in the optimization to get at least 65536 passes in forward testing. I don't think my code or my computer is the problem. That being said I would think these issues would have been brought up before though if it wasn't just me. The only other mention of the first bug is in forum post 382346. The other bugs I don't know how to word them in a google search but I don't think anyone has posted about those either. Let me know if my code could be the problem and I'll try to get it to bug out on a simplified version of my EA. I hope I worded everything well enough for you to understand. I can run more tests if you need but it will just take a while as each one takes a couple days.  Anyway these bugs have cost me many many hours of my life so I hope these can get fixed.