MCXLAB ERROR -4 in unit mcx_core.cu:1228: unspecified launch failure

[Timothy Sowers]

Hi Dr. Fang, 

I've been running MCXLAB without troubles since my last message to you.  Without making any conscious changes to my setup, this error popped up: 

MCXLAB ERROR -4 in unit mcx_core.cu:1228: unspecified launch failure

Error from thread (0): unspecified launch failure

C++ Error: MCXLAB Terminated due to an exception!

I downloaded the nightly build and the same problem remained.  

Interestingly, the basic demo works fine.  The problem only showed up during the spatial frequency source (plot 7) of the source type example.  My personal codes don't work at all.  

I also checked the TdrDelay values and they are still present, both in the CurrentControlSet and ControlSet001 (I have no ControlSet002, which from what I've read some people have).  I also did the updates to drivers that worked for me last time, to no avail.  

Based on the error type, do you have any opinions on what might be causing these errors?  

Thanks again, 

Tim

[Qianqian Fang]

hi Tim

plot 7 in demo_source_type is the only simulation in the entire demo scripts that
may need longer than 5-10 seconds. so I think it was likely killed by the driver.

can you delete the TdrDelay key, and then, run mcxstudio.exe in the same
folder as mcx.exe? it automatically detects TdrDelay setting, and prompts you
to write a proper setting to the registry. Please do a reboot after the key is
updated.

Let me know if this is still a problem.

Qianqian

Thanks again, 

Tim

--
You received this message because you are subscribed to the Google Groups "mcx-users" group.
To unsubscribe from this group and stop receiving emails from it, send an email to mcx-users+...@googlegroups.com.
To post to this group, send email to mcx-...@googlegroups.com.
Visit this group at https://groups.google.com/group/mcx-users.
For more options, visit https://groups.google.com/d/optout.

[Amaia Benitez]

Dear Dr. Fang,

I am using mcxlab (version 2017.7 (Dark Matter RC2), with an exisiting mcxlab.mexw64 file in it), CUDA 7.5, VS 11.0, Windows 10.

I have a similar issue as Timothy, but using the demo_4layer_head.m example. When I run the script in Matlab, I inmediately get the following output in the workspace:

(...)

GPU=1 (GeForce GTX 950M) threadph=4882 extra=8320 np=50000000 nthread=10240 maxgate=1 repetition=1

initializing streams ... init complete : 0 ms

requesting 2048 bytes of shared memory

lauching MCX simulation for time window [0.00e+00ns 5.00e+00ns] ...

simulation run# 1 ... 

then I get the following, after about 15min:

MCXLAB ERROR -4 in unit mcx_core.cu:1457: unspecified launch failure

Error from thread (0): unspecified launch failure

C++ Error: MCXLAB Terminated due to an exception!

Elapsed time is 949.539654 seconds.

If I run demo_mcxlab_basic, it takes some time, but it works:

GPU=1 (GeForce GTX 950M) threadph=976 extra=5760 np=10000000 nthread=10240 maxgate=50 repetition=1

initializing streams ... init complete : 0 ms

requesting 2304 bytes of shared memory

lauching MCX simulation for time window [0.00e+00ns 5.00e+00ns] ...

simulation run# 1 ... 

kernel complete:  65348 ms

retrieving fields ... detected 44748 photons, total: 44748 transfer complete: 65393 ms

data normalization complete : 65394 ms

normalizing raw data ... normalization factor alpha=1000.000000

simulated 10000000 photons (10000000) with 10240 threads (repeat x1)

MCX simulation speed: 153.03 photon/ms

total simulated energy: 10000000.00 absorbed: 27.15391%

(loss due to initial specular reflection is excluded in the total)

I hope I provided you with enough information. Could you perhaps point out what may be causing this problem and how to solve it?

Thank you,

Amaia.