Discussion Forum

Posted: 10 years ago 23 mars 2015, 12:21 UTC−4

Hello David, There is no limitation on the number of processors that your license can use. On the other hand a CPU license only allows one session at a time. For hardware recommendations, a good starting point is this link: http://www.comsol.com/support/knowledgebase/866/ This blog posting may also be useful to better understand RAM use: http://www.comsol.com/blogs/much-memory-needed-solve-large-comsol-models/ Our support team may have further insights: you can contact them at support@comsol.com . Best regards, Jeff

Posted: 10 years ago 24 mars 2015, 13:43 UTC−4

Hi David, I am also facing the same problem for simulating microwave problems. Please let me know if you get any solution of this. Thanks & Regards Ravinder

Posted: 10 years ago 24 mars 2015, 16:23 UTC−4

We are still trying to figure this out. From what I could learn from the recommended COMSOL links, I understand that performance is mostly dependent on the product of number of processors (not cores) and memory channels per processor (or total bandwidth). I see Intel has a board with 4 sockets for the E5-4600 v2 family. http://www.intel.com/content/www/us/en/motherboards/server-motherboards/server-board-s4600lh-s4600lt.html An moderate-priced processor from this family is: E5-4627 v2. Q1’14; 768 GB max; 60 GB/s; 8 cores; 3.3 GHz; DDR3; 20MB cache. The most expensive processor from the E5-4600 family is: E5-4657L v2. Q1’14; 768 GB max; 60 GB/s; 12 cores; 2.4 GHz; DDR3; 30MB cache. A cheap processor that appears similar in key points to the first listed above is: E5-2630 v3. Q3’14; 768 GB max; 59 GB/s; 8 cores; 2.5 GHz; DDR4; 20MB cache. Though I haven't found a 4-socket board for it. Here's a comparison of 7 high-end processors spanning an order-of-magnitude range in prices: http://ark.intel.com/compare/75290,81059,75287,75258,83359,83356,75253 Would appreciate any insights into the expected performance advantage of four E5-4657's vs four E5-4627's. Also, if anyone knows where to get a board with four sockets for a higher-end processor, such as, E7-8890-v2. Q1’14; 1546 GB max; 85 GB/s; 15 cores; 2.8 GHz; DDR3; 38MB cache, I would appreciate the pointer. David

Posted: 10 years ago 26 mars 2015, 11:10 UTC−4

Just to summarize what we've tentatively concluded. Looks like 4-socket boards (for Intel processors) are available only for the E5-4600 and E7-4800 series. We've decided to go with a 4-socket computer with four E5-4627 v2 processors with 256GB RAM (for now, a TB later), at a total cost of ~$20K, depending on various options. We're going for clock speed and bandwidth rather than number of cores, as we are always seeing very low CPU usage during the most frustration portions of our efforts, which are always the trial-and-error portions of trying to get COMSOL to finalize or mesh on what are perfectly good geometries. But we're having trouble finding E5-4627 v2 processors in stock. So we're looking for similar alternatives. Might end up spending a little more, as we're in a hurry to get something much better than what we've been using, which is a single i7-3930K with 64 GB RAM. We'll provide direct comparisons to what we've been using at some point after we have the new computer - probably in less than a month. We're hoping to be able to upgrade to a top-end 8-socket computer in 6-16 months, with eight E7-8890-v2 processors, or similar. That would probably cost ~$70K today. Hopefully it will be significantly less a year from now. Any suggestions and further advice would be appreciated. David

Posted: 10 years ago 26 mars 2015, 12:18 UTC−4

Hi, interesting project. Which 4 CPU mainboard did you choose? Have you seen this: http://www.supermicro.nl/products/motherboard/Xeon7000/#2011 ? So far my workhorse is also core I7, and planning to upgrade. Looking forward to hear about your experiences. -- Edgar J. Kaiser emPhys Physical Technology http://www.emphys.com