File system may be a bottleneck was my suspicion, too. However, I could not find any evidence the last time I tried. I compared running E+ job on a RAM drive and the conventional hard drive, but could not see much difference. My theory was that the cache provisions in modern operating systems and the hard drive itself are sufficient to handle E+?s I/O operations (sequential write) efficiently. So unless your computer is starved of memory, or the file system is overloaded by other programs, disk I/O is not a major issue.
E+ models can generate GBs of data in each run. But I think people are sensible enough not to do that too often. On the other hand, if disk I/O really is a bottleneck, there is a very simple solution: buy more memory and run E+ off a RAM drive.
Yi
From: EnergyPlus_Support@xxxxxxxxxxxxxxx [mailto:EnergyPlus_Support@xxxxxxxxxxxxxxx] On Behalf Of Jim Dirkes
Sent: 11 April 2013 17:34
AS has been mentioned in the past, E+ makes a lot of hard disk read / writes, so a fast hard drive also makes a difference. I use a solid state hard drive, but have not measured the impact.
James V Dirkes II, PE, BEMP, LEED AP
www.buildingperformanceteam.com
Energy Analysis, Commissioning & Training Services
1631 Acacia Drive, Grand Rapids, MI 49504 USA
616 450 8653
From: EnergyPlus_Support@xxxxxxxxxxxxxxx [mailto:EnergyPlus_Support@xxxxxxxxxxxxxxx] On Behalf Of Yi Zhang
Sent: Thursday, April 11, 2013 12:30 PM
To: EnergyPlus_Support@xxxxxxxxxxxxxxx
Subject: RE: [EnergyPlus_Support] Energy Plus simulation run
Yes, I second that!
You can see in the benchmark results that 64bit Linux version of E+ is faster than the 64bit Windows version, which is in turn faster than the 32bit Windows version. The overall difference can be as much as 25%.
Hardware makes a big difference, too. On average, the benchmark models take only 17 seconds to run on my £500 desktop, compared to 30 seconds on the 3 year old laptop (£1,500 when new!) Upgrade your computer may be well worth it, if you are going to use it often.
Cheers,
Yi
From: EnergyPlus_Support@xxxxxxxxxxxxxxx [mailto:EnergyPlus_Support@xxxxxxxxxxxxxxx] On Behalf Of Ivan Korolija
Sent: 10 April 2013 18:36
To: EnergyPlus_Support@xxxxxxxxxxxxxxx
Subject: Re: [EnergyPlus_Support] Energy Plus simulation run
Harshul,
In addition to Jean's and Jim's suggestions you might think about hardware upgrade :).
We've tested quite a few processors (http://www.iesd.dmu.ac.uk/~jeplus/wiki/doku.php?id=examples:tests:processor_speed_benchmarks) and the conclusion is clear:
more powerful processor = faster simulations.
We also found that the Linux version is up to 10% faster than the Windows version tested on the same hardware.
Cheers,
Ivan
Dr Ivan Korolija
IESD, De Montfort University, Leicester, UK
From: harshul <harshul263@xxxxxxxxxxx>
To: EnergyPlus_Support@xxxxxxxxxxxxxxx
Sent: Wednesday, April 10, 2013 2:21 AM
Subject: [EnergyPlus_Support] Energy Plus simulation run
Hi
My IDF file is 1.5 mb and it takes half an hour to run the simulation? Is there any technique to make it fast?
Thanks
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