<div dir="ltr"><div>Hi Erik,</div><div><br></div><div>I'm sorry for the late reply. I'm replying to ET as well to hear from others about my short comments below.</div><br><div class="gmail_quote"><div dir="ltr" class="gmail_attr">On Thu, Jul 8, 2021 at 11:07 PM Erik Schnetter <<a href="mailto:schnetter@cct.lsu.edu">schnetter@cct.lsu.edu</a>> wrote:<br></div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex">Hee Il<br>
<br>
This looks disconcerting. Using vectorization or not should only<br>
affect things at the round-off level (the same way parallelization<br>
does).<br></blockquote><div><br></div><div>I agree with you. But I'm not 100% sure myself whether I can ignore any chance of dynamical instabilities owing to the round-off, even though it would be extremely rare.</div><div><br></div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex">
<br>
The vectorization settings you show look good.<br>
<br>
I'd like to dig deeper.<br>
<br>
- Is your source code public, or would you be willing to share it with<br>
a few developers?<br></blockquote><div><br></div><div>At least for this issue, I'm using public ET codes (mainly Turing version).</div><div> </div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex">
- Is your parameter file public, or would you be willing to share it<br>
with a few developers?<br></blockquote><div><br></div><div>Not public. I guess that this vectorization issue would be reproducible in any circumstances if the resolutions are sufficiently high. For example, the resolution used here is dxmin=0.25 num_levels=6, and dtfac=0.4. I can share with you a public EOS version.</div><div> </div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex">
- The first thing to do is probably to look at other, more fundamental<br>
variables (e.g. metric components) in 3d and see where they begin to<br>
differ. The hope is that they would begin to differ early during the<br>
run. Do you have such 3d output at the same time from both<br>
simulations? Or do you have 1d output e.g. along the x axis for some<br>
variables?<br></blockquote><div><br></div><div>I can make you an account on my machine to access the data. I will let you know if I gather the data.</div><div><br></div><div>Hee Il</div><div><br></div><div><br></div><div><br></div><div><br></div><div><br></div><div><br></div><div> </div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex">
<br>
-erik<br>
<br>
<br>
On Thu, Jul 8, 2021 at 9:01 AM Hee Il Kim <<a href="mailto:heeilkim@gmail.com" target="_blank">heeilkim@gmail.com</a>> wrote:<br>
><br>
> Hi all,<br>
><br>
> While examining different results from my colleague's, I found the vectorization option could develop misleading results. I seldom use the vectorization option but in the configuration file but he mixed up with mine and others leaving:<br>
><br>
> VECTORISE = yes<br>
> VECTORISE_ALIGNED_ARRAYS = no<br>
> VECTORISE_INLINE = yes<br>
><br>
> in the config file. I found these are default config options in recent simfactory optionlists. Instead, I used to use AVX but always adding e.g., "-fp-model precise" for value safeness.<br>
><br>
> I attached two figures with the vectorization on/off. For the case of no vectorization, I tested it w/wo AVX and got the identical result.<br>
><br>
> Hee Il<br>
><br>
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<br>
<br>
<br>
-- <br>
Erik Schnetter <<a href="mailto:schnetter@cct.lsu.edu" target="_blank">schnetter@cct.lsu.edu</a>><br>
<a href="http://www.perimeterinstitute.ca/personal/eschnetter/" rel="noreferrer" target="_blank">http://www.perimeterinstitute.ca/personal/eschnetter/</a><br>
</blockquote></div></div>