Error in Black lanczos Eigensolver- Failed to allocate Memory

- June 11, 2023 at 2:00 pm
  
  balaji.bp
  Subscriber
  
  While solving the Modal analysis i am gettin gthe following error , which i i feel because of memory issue only. Here i was using the quadratic elements , when i changed it into the linear elemnt it solved my modal analysis in just 20 minutes but quadratic it showing this error. As quadratic are better i wanted to use that element, so could please tell any possible solution . FYI my PC confiuration is 512 Gb Ram 3 Tb harddisk with 64 core.
  
  Time at end of element matrix formulation CP = 222.84375.
  
  BLOCK LANCZOS CALCULATION OF UP TO    20 EIGENVECTORS.
  NUMBER OF EQUATIONS              =     16595622
  MAXIMUM WAVEFRONT                =          692
  MAXIMUM MODES STORED             =           20
  MINIMUM EIGENVALUE               = 0.00000E+00
  MAXIMUM EIGENVALUE               = 0.10000E+31
  
  Process memory allocated for solver              =     6.502 GB
  Process memory required for in-core solution     =     6.194 GB
  Process memory required for out-of-core solution =     2.019 GB
  
  Total memory allocated for solver                =   333.150 GB
  Total memory required for in-core solution       =   317.367 GB
  Total memory required for out-of-core solution   =    80.078 GB
  
  *** NOTE ***                            CP =     337.531   TIME= 21:20:07
  The Distributed Sparse Matrix Solver used by the Block Lanczos
  eigensolver is currently running in the in-core memory mode. This
  memory mode uses the most amount of memory in order to avoid using the
  hard drive as much as possible, which most often results in the
  fastest solution time. This mode is recommended if enough physical
  memory is present to accommodate all of the solver data.
  
  Total memory available for LANCZOS         =     115.954578 GB
  
  *** ERROR ***                           CP =    1056.375   TIME= 21:27:03
  Failed to allocate memory.
  
  *** ERROR ***                           CP =    1056.375   TIME= 21:27:03
  Failure in BLOCK LANCZOS eigensolver. Error code = -1. Please send
  the data leading to this operation to your technical support provider,
  as this will allow ANSYS, Inc to improve the program.
  
  *** WARNING ***                         CP =    1056.375   TIME= 21:27:03
  Fewer modes than the requested number of modes ( 20 ) were computed.
  There are only 0 modes beyond the begin frequency of FREQB= 0.
  
  *** ERROR ***                           CP =    1059.266   TIME= 21:27:06
  Failed to allocate memory.
  
  *** ERROR ***                           CP =    1059.266   TIME= 21:27:06
  Failed to allocate memory.
  
  *** ERROR ***                           CP =    1059.266   TIME= 21:27:06
  Failed to allocate memory.
  
  *** ERROR ***                           CP =    1059.266   TIME= 21:27:06
  Failed to allocate memory.
  
  *** ERROR ***                           CP =    1059.266   TIME= 21:27:06
  Failed to allocate memory.
  
  *** ERROR ***                           CP =    1059.266   TIME= 21:27:06
  Failed to allocate memory.
  
  *** ERROR ***                           CP =    1059.266   TIME= 21:27:06
  Failed to allocate memory.
  
  *** ERROR ***                           CP =    1059.266   TIME= 21:27:06
  Failed to allocate memory.
  
  *** ERROR ***                           CP =    1059.266   TIME= 21:27:06
  Failed to allocate memory.
  
  *** ERROR ***                           CP =    1059.266   TIME= 21:27:06
  Failed to allocate memory.
  
  *** ERROR ***                           CP =    1059.266   TIME= 21:27:06
  Failed to allocate memory.
  
  *** ERROR ***                           CP =    1059.266   TIME= 21:27:06
  Failed to allocate memory.
  
  *** ERROR ***                           CP =    1059.266   TIME= 21:27:06
  Failed to allocate memory.
  
  *** ERROR ***                           CP =    1059.266   TIME= 21:27:06
  Failed to allocate memory.
  
  *** ERROR ***                           CP =    1059.266   TIME= 21:27:06
  Failed to allocate memory.
  
  *** ERROR ***                           CP =    1059.266   TIME= 21:27:06
  Failed to allocate memory.
  
  *** ERROR ***                           CP =    1059.266   TIME= 21:27:06
  Failed to allocate memory.
  
  *** ERROR ***                           CP =    1059.266   TIME= 21:27:06
  Failed to allocate memory.
  
  *** ERROR ***                           CP =    1059.266   TIME= 21:27:06
  Failed to allocate memory.
  
  *** ERROR ***                           CP =    1059.266   TIME= 21:27:06
  Failed to allocate memory.
  
  *** ERROR ***                           CP =    1059.266   TIME= 21:27:06
  Failed to allocate memory.
  
  *** ERROR ***                           CP =    1059.266   TIME= 21:27:06
  Failed to allocate memory.
  
  *** ERROR ***                           CP =    1059.266   TIME= 21:27:06
  Failed to allocate memory.
  
  *** ERROR ***                           CP =    1059.266   TIME= 21:27:06
  Failure in BLOCK LANCZOS eigensolver. Error code = -1. Please send
  the data leading to this operation to your technical support provider,
  as this will allow ANSYS, Inc to improve the program.
  
  *** ERROR ***                           CP =    1059.266   TIME= 21:27:06
  Failure in BLOCK LANCZOS eigensolver. Error code = -1. Please send
  the data leading to this operation to your technical support provider,
  as this will allow ANSYS, Inc to improve the program.
  
  *** ERROR ***                           CP =    1059.266   TIME= 21:27:06
  Failure in BLOCK LANCZOS eigensolver. Error code = -1. Please send
  the data leading to this operation to your technical support provider,
  as this will allow ANSYS, Inc to improve the program.
  
  *** ERROR ***                           CP =    1059.266   TIME= 21:27:06
  Failure in BLOCK LANCZOS eigensolver. Error code = -1. Please send
  the data leading to this operation to your technical support provider,
  as this will allow ANSYS, Inc to improve the program.
  
  *** ERROR ***                           CP =    1059.266   TIME= 21:27:06
  Failure in BLOCK LANCZOS eigensolver. Error code = -1. Please send
  the data leading to this operation to your technical support provider,
  as this will allow ANSYS, Inc to improve the program.
  
  *** ERROR ***                           CP =    1059.266   TIME= 21:27:06
  Failure in BLOCK LANCZOS eigensolver. Error code = -1. Please send
  the data leading to this operation to your technical support provider,
  as this will allow ANSYS, Inc to improve the program.
  
  *** ERROR ***                           CP =    1059.266   TIME= 21:27:06
  Failure in BLOCK LANCZOS eigensolver. Error code = -1. Please send
  the data leading to this operation to your technical support provider,
  as this will allow ANSYS, Inc to improve the program.
  
  *** ERROR ***                           CP =    1059.266   TIME= 21:27:06
  Failure in BLOCK LANCZOS eigensolver. Error code = -1. Please send
  the data leading to this operation to your technical support provider,
  as this will allow ANSYS, Inc to improve the program.
  
  *** ERROR ***                           CP =    1059.266   TIME= 21:27:06
  Failure in BLOCK LANCZOS eigensolver. Error code = -1. Please send
  the data leading to this operation to your technical support provider,
  as this will allow ANSYS, Inc to improve the program.
  
  *** ERROR ***                           CP =    1059.266   TIME= 21:27:06
  Failure in BLOCK LANCZOS eigensolver. Error code = -1. Please send
  the data leading to this operation to your technical support provider,
  as this will allow ANSYS, Inc to improve the program.
  
  *** ERROR ***                           CP =    1059.266   TIME= 21:27:06
  Failure in BLOCK LANCZOS eigensolver. Error code = -1. Please send
  the data leading to this operation to your technical support provider,
  as this will allow ANSYS, Inc to improve the program.
  
  *** ERROR ***                           CP =    1059.266   TIME= 21:27:06
  Failure in BLOCK LANCZOS eigensolver. Error code = -1. Please send
  the data leading to this operation to your technical support provider,
  as this will allow ANSYS, Inc to improve the program.
  
  *** ERROR ***                           CP =    1059.266   TIME= 21:27:06
  Failure in BLOCK LANCZOS eigensolver. Error code = -1. Please send
  the data leading to this operation to your technical support provider,
  as this will allow ANSYS, Inc to improve the program.
  
  *** ERROR ***                           CP =    1059.266   TIME= 21:27:06
  Failure in BLOCK LANCZOS eigensolver. Error code = -1. Please send
  the data leading to this operation to your technical support provider,
  as this will allow ANSYS, Inc to improve the program.
  
  *** ERROR ***                           CP =    1059.266   TIME= 21:27:06
  Failure in BLOCK LANCZOS eigensolver. Error code = -1. Please send
  the data leading to this operation to your technical support provider,
  as this will allow ANSYS, Inc to improve the program.
  
  *** ERROR ***                           CP =    1059.266   TIME= 21:27:06
  Failure in BLOCK LANCZOS eigensolver. Error code = -1. Please send
  the data leading to this operation to your technical support provider,
  as this will allow ANSYS, Inc to improve the program.
  
  *** ERROR ***                           CP =    1059.266   TIME= 21:27:06
  Failure in BLOCK LANCZOS eigensolver. Error code = -1. Please send
  the data leading to this operation to your technical support provider,
  as this will allow ANSYS, Inc to improve the program.
  
  *** ERROR ***                           CP =    1059.266   TIME= 21:27:06
  Failure in BLOCK LANCZOS eigensolver. Error code = -1. Please send
  the data leading to this operation to your technical support provider,
  as this will allow ANSYS, Inc to improve the program.
- June 14, 2023 at 12:13 pm
  
  Aniket
  Forum Moderator
  
  Hi Bala, it seems the issue of large model, can you try reducing the mesh count while keeping quadratic elements?
  As per table 4.3 it may take 374 to 664 GB RAM to solve this model in core.
  https://ansyshelp.ansys.com/account/Secured?returnurl=/Views/Secured/corp/v231/en/ans_per/perlineqsolv.html%23d0e1145
  you may want to try using DSPOPTION https://ansyshelp.ansys.com/account/Secured?returnurl=/Views/Secured/corp/v231/en/ans_cmd/Hlp_C_DSPOPTION.html and force this analysis out of core. Please note you will need about 664 GB hard drive space in that case. Also, that hard drive space should be in the same partition where the temp directory is located:
  -Aniket
  How to access Ansys help links
  Guidelines for Posting on Ansys Learning Forum
- June 15, 2023 at 6:32 am
  
  balaji.bp
  Subscriber
  
  Thanks for detail reply. This out of core option has worked it solved my modal analysis, but further when i tried to to solve transient analysis by using MSUP its crashing the Ansys mechanical. Due to some reason i had to interrupt my transient analysis solution process, but after doing this my ansys mechanical is not opening , just crashing when i am trying to open.
  - June 15, 2023 at 9:50 am
    
    Aniket
    Forum Moderator
    
    In that case, a bigger machine or smaller mesh would be the only option.
    -Aniket
    How to access Ansys help links
    Guidelines for Posting on Ansys Learning Forum