-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 adrian wrote: > Hi, everyone: > We are considering for buying one PC to run MEEP . > The number of points in my usual case is around 125e+6, corresponding > to 5.722GB. > Additionally, we use dispersive material. > I use long wavelength such as 1550nm and resolution is 0.5 for length > unit being 1nm. > ( Since the minimum feature size in my case is 20nm)
You should simulate a small sub-volume on your current hardware first. On a single computer, Meep requires time and memory exactly proportional to volume, so you can calculate how much CPU and RAM it will take to solve the large problem. > I find one PC dedicated for runing FDTD has specs as following: > > Choice of 8 or 16 GB RAM dedicated for > CelerityTM Acceleration Board. > • Intel Pentium IV 3.2 GHz CPU with Hyper > Threading > • 4 GB DDR PC3200 (400 MHz) SDRAM > (motherboard RAM) > • More than one terabyte of storage > from OptoFDTD Max > > I am wondering if such a hardware is sufficient to support MEEP, for > my case or > I have to strengthen some hardware like memory or speed of CPU. You will probably need much more main memory, and a large number of CPUs. The acceleration hardware is useless for Meep. For RAM, you will need 6 GB just to store the fields. Meep keeps several copies of the fields in memory, so figure 18 GB for the fields. You will also need to store the media, so figure an additional 6 GB for that. 32GB of RAM might be enough, but you will probably want more. > Or, It's better to use workstation with parallel process and clusters? > If so, what kind of facility do I need? Most people who use Meep for large calculations seem to use computing clusters. Cluster speed is limited by network speed. In my experience, Gigabit network is acceptable if each machine can be given at least a 64x64x64 cube. The larger each computer's simulation volume is, the less important network speed is. With a computing cluster, you do not need all this memory in one machine, but you still need at least as much memory in total. - --Ben -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.7 (GNU/Linux) Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org iD8DBQFHXglPUJT6e6HFtqQRAhaSAJ95nzhtO37arA+8KuGnI0x4XutHNwCeP0kT 6a0pV7eM1EVReKqVm82SBJM= =pJ+u -----END PGP SIGNATURE----- _______________________________________________ meep-discuss mailing list [email protected] http://ab-initio.mit.edu/cgi-bin/mailman/listinfo/meep-discuss
