For Parameter Settings

The 3D simulation is bounded by the total memory size. The code requires

$$\begin{align} \begin{split} &m_\text{MP} = 116 + 24 \mathtt{NM} = 188 \quad (\mathtt{NM}=3) \quad \text{byte} \\ \end{split}\end{align}$$

of memory for the case of mixed precision (MP=DP) with a GNZ viscoelastic body of NM=3. Note that this is a coarse estimate excluding the effect of an absorbing boundary.

The computation time can be roughly estimated by the parameter $\mathtt{n_G}$, which is defined as the number of spatial and/or temporal grids that one CPU can process in a second. This value depends on the CPU, as shown in the following table.

Architecture Name	CPU	#Core	$\mathtt{n_G}$
Mac Pro 2010	Intel Xeon X5670 2.93GHz	6	$6.7 \times 10^{6}$
EIC2015 (ERI,UTokyo)	Intel Xeon E5-2680 v3 2.5 GHz	12	$7.0 \times 10^{6}$
The earth simulator (3rd gen.)	NEC SX-ACE	4	$57 \times 10^{6}$

The total computation time can be estimated by

$$\begin{align} t_\text{comp} = \frac{ {\tt nx}\times {\tt ny}\times {\tt nz}}{ \mathtt{n_G} \times \tt nproc} \times {\tt nt} \quad \text{[s]}\end{align}$$

where ncore is the number of CPU cores used in the computation. If the estimated time exceeds that provided by the computer system, it is recommended to make the model size smaller and/or to use checkpointing/restarting.