<html xmlns:v="urn:schemas-microsoft-com:vml" xmlns:o="urn:schemas-microsoft-com:office:office" xmlns:w="urn:schemas-microsoft-com:office:word" xmlns:m="http://schemas.microsoft.com/office/2004/12/omml" xmlns="http://www.w3.org/TR/REC-html40"><head><meta http-equiv=Content-Type content="text/html; charset=us-ascii"><meta name=Generator content="Microsoft Word 14 (filtered medium)"><style><!--
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</o:shapelayout></xml><![endif]--></head><body lang=EN-US link=blue vlink=purple><div class=WordSection1><p class=MsoNormal>Hi guys.<o:p></o:p></p><p class=MsoNormal>I am a computer science guy without any background in fluid dynamics solver. I am using Nek5000 for the fault tolerance research. In particular, I inject random errors into data structures of Nek5000 and then record how Nek5000 reacts. Currently, I have a problem about how to judge the performance of Nek5K with injected faults is normal (i.e., tolerating fault) or not. I can simply record the execution time and then compare time difference. However, some injected errors might not lead to time variance while making the simulation result invalid. Is there any metric I can use to evaluate if the simulation result is valid/reasonable (especially for the eddy and/or vortex problem)? For example, a X error rate beyond a threshold after a fixed number of timesteps, or something?<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Thank you very much.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>-Dong<o:p></o:p></p></div></body></html>