× If you have problems during the execution of MRCC, please attach the output with an adequate description of your case as well as the followings:
  • the way mrcc was invoked
  • the way build.mrcc was invoked
  • the output of build.mrcc
  • compiler version (for example: ifort -V, gfortran -v)
  • blas/lapack versions
  • as well as gcc and glibc versions

This information really helps us during troubleshooting :)

Acceleration in CCSDT calculation

More
3 months 2 weeks ago - 3 months 2 weeks ago #804 by duanchenru
Dear MRCC developers,

I am running CCSDT calculations on small transition metal complexes using MRCC2019. I found that one iteration of CCSDT can take up to 8 hours for a system of 121 basis function. I know that CCSDT calculations are expensive but I am still wondering if I did something wrong to make it this slow. For example, if I could allocate more memory to reduce the file I/O on the disk? Below I attach the essential inputs of mine as well as the output file. Thanks in advance for your help.

Best,
Chenru

======input=======
calc=ccsdt
ovirt=off
rest=2
cialg=direct2
core=frozen
scftype=rohf
rohftype=semicanonical
dens=0
mem=64GB
usedist=1
mult=2
charge=2
===================

=======output========
Executing goldstone...

Generation of MRCC equations in terms of H and T...
Generation of antisymmetrized Goldstone diagrams...
Number of diagrams in T^1 equations: 15
Number of diagrams in T^2 equations: 37
Number of diagrams in T^3 equations: 47
Translation of diagrams to factorized equations...
Number of restricted diagrams in T^1 equations: 30
Number of restricted diagrams in T^2 equations: 126
Number of restricted diagrams in T^3 equations: 274
Optimizing intermediate calculation...
Number of floating-point operations per iteration step: 2.2488E+14
Probable CPU time per iteration step (hours): 2248.77
Required memory (Mbytes): 21353.1
Number of intermediates: 210
Number of intermediates to be stored: 100
Length of intermediate file (Mbytes): 49946.4

************************ 2020-02-16 12:47:24 *************************
Executing xmrcc...

**********************************************************************
MRCC( 3 ) calculation


Allocation of****** Mbytes of memory...
Number of spinorbitals: 246
Number of alpha electrons: 16
Number of beta electrons: 15
Number of active particles: 108
Number of active holes: 0
Spin multiplicity: 2
z-component of spin: 0.5
Spatial symmetry: 1
Convergence criterion: 1.0E-06
Construction of occupation graphs...
Number of 0 -fold excitations: 1
Number of 1 -fold excitations: 3332
Number of 2 -fold excitations: 4060650
Number of 3 -fold excitations: 2345138260
Total number of configurations: 2349202243
Calculation of coupling coefficients...
Length of intermediate file (Mbytes): 36278.4

======================================================================

Memory requirements /Mbyte/:
Minimal Optimal
Real*8: 36145.9237 36145.9237
Integer: 58.1929
Total: 36204.1166 36204.1166


************************ 2020-02-16 12:47:35 *************************
Executing mrcc...

**********************************************************************
CCSDT calculation


OpenMP parallel version is running.
Number of CPUs: 16
Allocation of36145.9 Mbytes of memory...
Number of spinorbitals: 246
Number of alpha electrons: 16
Number of beta electrons: 15
Number of active particles: 108
Number of active holes: 0
Spin multiplicity: 2
z-component of spin: 0.5
Spatial symmetry: 1
Convergence criterion: 1.0E-06
Construction of occupation graphs...
Number of 0-fold excitations: 1
Number of 1-fold excitations: 3332
Number of 2-fold excitations: 4060650
Number of 3-fold excitations: 2345138260
Total number of determinants: 2349202243
Calculation of coupling coefficients...
Initial cluster amplitudes are read from unit 16.
Length of intermediate file (Mbytes): 36278.4
Reading integral list from unit 55...
Sorting integrals...
Sorting integrals...
Sorting integrals...
Sorting integrals...
Energy of reference determinant [au]: -1557.177195858343
Calculation of MP denominators...

Starting CC iteration...
==========================
Last edit: 3 months 2 weeks ago by duanchenru.

Please Log in or Create an account to join the conversation.

More
3 months 2 weeks ago #805 by kallay
Dear Chenru,
This is an expensive calculation as your molecule has no symmetry (at least, mrcc recognizes it as C1; you should provide more symmetrical coordinates if your molecule do have some symmetry). The only thing you can do to accelerate the calculation is to run it on a machine with larger memory.

Best regards,
Mihaly Kallay

Please Log in or Create an account to join the conversation.

More
3 months 2 weeks ago #809 by duanchenru
Dear Mihaly,

Thank you so much for your speedy reply. I will try playing around with the symmetry. In terms of using a machine of larger memory, I am wondering that now it seems only using 36204.1166 MB memory (I allocated 64 GB) and writing 36278.4 MB intermediate file. Do you think it will be accelerated if I use a machine with >73GB memory? Sorry I do not know whether I read the out file correctly and will be appreciated for your further help.

Best,
Chenru

Please Log in or Create an account to join the conversation.

More
3 months 2 weeks ago #810 by kallay
Dear Chenru,
I can tell you only on the basis of the output. Please post it.

Best regards,
Mihaly Kallay

Please Log in or Create an account to join the conversation.

More
3 months 2 weeks ago #811 by duanchenru
Here is the out file. Thank you so much!

Chenru


File Attachment:

File Name: mrcc_2020-02-21.txt
File Size:51 KB
Attachments:

Please Log in or Create an account to join the conversation.

More
3 months 1 week ago #812 by kallay
At least 145GB would be required for optimal performance.

Best regards,
Mihaly Kallay
The following user(s) said Thank You: duanchenru

Please Log in or Create an account to join the conversation.

Time to create page: 0.027 seconds
Powered by Kunena Forum