Viewing a Solution Profile in Q3D

At any time during or after the solution process, you can examine the computing resources or profile data that were used during the analysis. The profile data is essentially a log of the tasks performed by during the solution. The log indicates the length of time each task took and how much physical/disk memory was required.

From the Project Manager, right-click the solution setup and select Profile from the shortcut menu.

The Solutions dialog box appears, on the Profile tab. The displayed data depends on the type of problem and solution setup. If one or more dependent setups exist, the profile information for these can be selected from drop-down menu in the Simulation text field at the top of the dialog box.

In general, you can view the following information:


Task Lists the type of task that was performed. The Tasks lists included Start, various Mesh tasks, Simulation Setup, Port Adaptation, Adaptive Pass tasks, including simulation setup, Matrix Assembly, Solver tasks, and Field Recovery, Sweep tasks, and Solution Process summary and Totals for time.
Real Time The difference in time between the start of the task and the end of the task (elapsed time).
CPU Time The amount of CPU time required to perform the task.
Memory The peak amount of physical memory (RAM) used by the individual executable running the task. The memory is freed for other uses after each task is complete.
Information General information about the solution, for example, the number of tetrahedra used in the mesh, disk use, solver information, sweep information, and totals.

The matrix solver writes specific information in some of these fields as outlined below.


Task

The matrix solver task reports the type of solution performed by the solver, based on the physics of the problem.

It takes the format "Solver pdsn" where:

  • Precision Type p = M (Mixed, for Direct Solver) or D (Double, for Iterative Solver)
  • Matrix Data Type d = R (Real) or C (Complex)
  • Symmetry Type s = S (Symmetric), A (Asymmetric), or H (Hermitian)
  • n = Number of processors used. Specify the number available on the local machine. If a solve does not require all available processors, the number reported may be less than the number available.

Examples: Solver MRS2 or Solver DCS4-L2.

If a simulation uses the iterative solver, the Solver designation can include a level indicator appended to an Iterative solver designation (L2 in the example above). The higher the Level, the lower the memory. You will never see L1, as this would be equivalent to Direct Solver. A first order solve will only display L2 since it only has one level of order to go down for preconditioning. A second or mixed order solve may display L3, depending on the mesh quality.

Information

The matrix solver information line includes:

  • Disk – the amount of hard disk space used during the calculation of the matrix solution (for example, 0 KBytes). If the disk usage for matrix solver is non-zero in profile, it usually indicates off-core matrix solver. If the matrix solver must solve off-core, smaller blocks of the data to be solved are created on disk, each block is then solved in physical memory, and then the matrix solution is reassembled. As a result of this additional processing, the time required to calculate a solution is higher.
  • Matrix Size – the size of the matrix that was solved (for example, 11137).
  • Matrix Bandwidth – An FEM matrix is a sparse matrix. The solver only stores the non-zero entries. The matrix bandwidth is the average number of non-zeros per row (for example, 20.3). It gives an idea of the sparsity of a FEM matrix.Storage for the sparse matrix is proportional to the total number of nonzeros = #rows x bandwidth. The higher the bases order, the larger the bandwidth.
  • Number of Iterations – used with Iterative Solver.

To export the profile data:

  1. Open the Solutions dialog box. The Profile tab should already be selected.
  2. Click Export Profile.

This opens a file save dialog that lets you provide a file name and location.

  1. Click Save.

The data is saved in a text file with a .prof extension.