Users October 2020

users@lists.einsteintoolkit.org

18 participants
23 discussions

Postdoc positions at UIUC
by Helvi Witek 11 Nov '20

11 Nov '20

Dear all, we are opening two postdoc positions in numerical relativity at the University of Illinois in Urbana-Champaign (UIUC). The application deadline is 1 December 2020. You can find detailed information in our announcements: https://hyperspace.uni-frankfurt.de/2020/09/30/postdoctoral-postion-with-fo… https://hyperspace.uni-frankfurt.de/2020/09/14/postdoctoral-research-positi… We would greatly appreciate if you would share this information with potential candidates. Best wishes Helvi -- --------------------------------------------- Dr. Helvi Witek Assistant Professor Department of Physics University of Illinois at Urbana-Champaign 247 Loomis Lab 1110 W Green St Urbana, IL 61801 ---------------------------------------------

2 1

NRPyPN: Vote during November 12 Telecon
by Zach Etienne 05 Nov '20

05 Nov '20

Hello everyone, As we discussed during our weekly Einstein Toolkit telecon today (Oct 29), we will be having a vote on November 12 to determine whether to include NRPyPN into the Toolkit. Proposing a vote such as this requires at least one week notice sent to the users mailing list. This email serves as that notice. Please respond to this message if you have any objections to including NRPyPN in the next (late-November) Toolkit release, so we can discuss. Thanks everyone, and we hope to see you during our next telecon (Nov 5)! -Zach * * * Prof. Zachariah Etienne Physics & Astronomy Dept. West Virginia University http://astro.phys.wvu.edu/zetienne/ http://blackholesathome.net <https://blackholesathome.net>

2 1

nan using Carpet
by Garrison, David 30 Oct '20

30 Oct '20

Hello, I’m switching a code I wrote from using PUGH to using Carpet but now I get lots of NAN’s when I run it. Are there any special parameters needed to run Carpet as unigrid and behave like PUGH? I am also using MoL and get this issue even when I use Euler methods and trivial initial data. -DG

2 3

Meetings Minutes 2020-10-29
by Hamilton, Maria 29 Oct '20

29 Oct '20

Participants: Beyhan, Peter Diener, Bill Gabella, Zach Etienne, Atul Kedia, Kenneth Sible, M. Garcia, Roland Haas, Samuel Cupp, Yosef Zlochower and Maria Babiuc Hamilton. Chair: Zach E. Minutes: Maria H. Zach: The first item on the agenda is the timeline until the next release. The most important reminder is that the hard release is on Thanksgiving Thursday and everything must be reviewed by then. What is the status of the gallery tests and of the test suites? Roland: Found runners of all gallery tests, we are in good shape. Rerun all test suites once a week, nothing breaking, the only issues are seen with GPU support, it might be an easy fix. Also, the new added tests that are using ADMConstraints fail, again it might be an easy fix. Test suites hang on Mac, but this is not necessarily an issue. Anybody willing to investigate the GPU failing? Zach: The code marked for inclusion in the upcoming release is NRPyPN. Fixed the big things. Instructions are right there at the bottom of the documentation. A discussion ensues between Zach and Roland regarding the documentation of the functions in NRPyPN. Zach will work on it this coming week. The inclusion vote will happen via email, before Thanksgiving Thursday. Zach: Next are the tickets, unanswered questions in the mailing list. Roland: there are 17 tickets, among which more relevant Issue #2212/Issue #2206 regarding Lorene, and #2332/#2089 regarding piraha. Peter worked on stability with summation by parts ticket #2368 during meeting and sent a pull request. Next there are some questions from the participants. M. Garcia asks what machine files spn, npn, stand for. Roland refers him to https://docs.einsteintoolkit.org/et-docs/Configuring_a_new_machine Maria sees a -ludev error, and is instructed to install libudev-dev. Beyhan has a more extensive question, on how to change the beta driver for binary neutron stars in McLachlan. Zach answers with a short explanation on how he managed to change the gamma driver shift parameter. He will send Beyhan an email with his documentation. Beyhan has another question on how to mark the location of the stars, and Zach answers by explaining how to employ VolumeIntegral_GRMHD. Roland points out that all symmetries should be turned off if this diagnostic is used. After chairs and minute takers volunteers are enlisted for the next two weeks, Zach closes the meeting. ... Maria _______________________ Maria C. Babiuc Hamilton, Ph.D. Professor, Department of Physics College of Science, Marshall University, 1 John Marshall Drive, Huntington, WV, 25755 Room S 257, Phone: (304)696-2754

1 0

VisIt and Pugh
by Garrison, David 29 Oct '20

29 Oct '20

Has anyone use VisIt to visualize HDF5 data generated using the PUGH driver or does it just work with Carpet? -DG

2 1

ld error in development ETK on Ubuntu
by Hamilton, Maria 28 Oct '20

28 Oct '20

Hi, I need help with an error I am seeing after a recent update to Ubuntu 20.04 The error is: /usr/bin/ld: cannot find -ludev collect2: error: ld returned 1 exit status make[1]: *** [/home/babiuc/Cactus/lib/make/make.configuration:150: /home/babiuc/Cactus/exe/cactus_sim] Error 1 Maria _______________________ Maria C. Babiuc Hamilton, Ph.D. Professor, Department of Physics College of Science, Marshall University, 1 John Marshall Drive, Huntington, WV, 25755 Room S 257, Phone: (304)696-2754

1 0

Agenda for Thursday's Meeting
by users＠einsteintoolkit.org 26 Oct '20

26 Oct '20

Please update the Wiki with agenda items for Thursday's meeting. Thanks! https://docs.einsteintoolkit.org/et-docs/meeting_agenda --The Maintainers

2 1

TOV Solver and Equilibrium
by Nick Olsen 22 Oct '20

22 Oct '20

Hello I am a master's student working on general relativity and in my project we have gotten to a point where we need to solve the Einstein equations. We are not numerical relativity experts but we have started getting familiarized with the Einstein Toolkit. After playing with it for a while I have realized that I can’t even run a very simple example where I get the TOV equilibrium parameter file from the par folder of the ET installation and modify it to take it a little bit out of equilibrium and see it numerically evolve back to a new equilibrium situation (say for example changing the density profile). I have tried modifying rho_central in the file tov_star.par however it seems that after that modification the system does not evolve to a new equilibrium. I was wondering if somebody here can point me in the right direction. Thank you so much in advance. Nicholas Olsen

2 1

Meeting Minutes 2020-10-22
by Gabella, William E 22 Oct '20

22 Oct '20

Attending: Maria HB, Bill G, Roland H, Yosef Z, Miguel GL, Peter D, Steve B, Zach E Chair: Maria HB Minutes: Bill G * transition cactuscode.org to github pages [RH, SB] Steve, process is Steve talking to IT support and also a couple of issues, referring an LSU domain to an external site, and mailing lists running off the old server. So in process, but keep reminding Steve. Roland, good if done for next release. Steve, it should be done by then, everything is fine, a guess is done in two weeks. * upcoming release planning (5.5 weeks to go, 3 weeks to feature freeze, 3 weeks to have everything reviewed) [RH] ** Gallery test runners search Release Details [RH] https://docs.einsteintoolkit.org/et-docs/Release_Details See the release dates and the timeline by Steve. Feature freeze on the 12th of Nov. Naming for next week, but we should think about it. See list in Release Details, under Tools/Links. Ask around for students to run these examples, and you get your name on the ET release. *** Single, stable neutron star https://bitbucket.org/einsteintoolkit/tickets/issues/2175/test-single-stabl… Miguel G.L. will do it. *** Multi Patch Scalar Wave Equation https://bitbucket.org/einsteintoolkit/tickets/issues/2174/test-multi-patch-… Need someone. *** Poisson equation https://bitbucket.org/einsteintoolkit/tickets/issues/2173/test-poisson-equa… Bill G for poisson solver. *** Binary neutron star https://bitbucket.org/einsteintoolkit/tickets/issues/2176/test-binary-neutr… Need someone. *** Binary black hole GW150914 https://bitbucket.org/einsteintoolkit/tickets/issues/2172/test-binary-black… Steve, would like to convert to a singularity image to run; he will think about it. ** release testsuite status http://einsteintoolkit.org/testsuite_results/index.php ** NRPyPN: ticket 2417. [PD, ZE] https://nbviewer.jupyter.org/github/zachetienne/nrpytutorial/blob/master/NR… https://bitbucket.org/einsteintoolkit/tickets/issues/2417 Zach, Zach is responding to Roland and Zach has started addressing the primary issue, making it a stand-alone that could go in an arrangements directory and run the notebooks from that directory. Roland modified the GetComponents to make this work. Should have an install directions file. Zach recommends a virtual environment especially to get the latest version of sympy. So good to know the minimum version (of Sympy say) that works. Earliest version of sympy which works is 1.2 which is old, July 2018. Roland, procedure for adoption is that it needs to be ready for release, we announce, and then there is a call for the vote. Likely vote in two weeks. * ICERM Fall 2020 tutorials post-action review [RH] ** NRPy+ (Zach) ** Writing your own Einstein Tookit thorns (Steve) Zach for NRPY and Steve for ETK. Steve, the LSU virtual machines worked well and putting a Cactus tarball in each users directory was a help, sped up the compile process. Would like Zach's tutorials in the same place for ease of use of the student. Zach, it should be possible. Steve, looking at Spack, Spack based dockers to check ET versus different Linux versions. Could also test various versions of MPI, etc, etc. spack = package manager for HPCs, and you can handle packages in your user space https://computing.llnl.gov/projects/spack-hpc-package-manager unanswered question on mailing list / open tickets sorted by update time / tickets ready for review * unanswered https://www.einsteintoolkit.org/tools/unanswered.php "Settings procs" and "Poisson equation" have responses and paths forward. "TOV Solver" we think is robust but changes equilibrium when rho_central is changed. Peter will respond. "Cartoon2D and McLachlan" Roland has responded to it. * open tickets https://bitbucket.org/einsteintoolkit/tickets/issues?status=open&status=new… Many of the tickets relate to the new release. Cactus math work-arounds breaking CarpetX, cannot be changed by next release. GCC discussion and see 4.8 on many platforms. With the GCC 10 fixes, it is broken on 4.8 and works on 4.9. Roland will have gcc 4.8 in the configure test and have it fail if the GCC 10 fixes are not successful there. GCC 4.8 nominally supports C++11. * review tickets https://bitbucket.org/einsteintoolkit/tickets/issues?status=new&status=open… #2288, Lean changes looked at by Miguel Zilhao, would like it to go in before the release. And Zach looking at Baikal. #2386, CCTK_Loop3_INT, is also something that Zilhao wants, but Lean fix is more important. * Next week chair is Zach and minute taker is Maria. -- ============================== William Gabella Research Assistant Professor Department of Physics and Astronomy Nashville, TN USA (o) 615-343-2713

1 0

Standard benchmark
by Gabriele Bozzola 22 Oct '20

22 Oct '20

Hello, I want to benchmark the Einstein Toolkit on a new POWER9 cluster. My goals are to understand how the code scales and how the performances compare with the ones on other supercomputers. Is there a standard benchmark suite that covers all the typical use-cases and stresses all the different moving components (including IO, inter-node communication, ...)? Is there a set of results on benchmarks/scaling on recent machines? I found some emails on the subject and a page on the wiki for old clusters, but I cannot track down what is the most recent information on the topic. Thanks, Gabriele Bozzola

2 1

2026

2025

2024

2023

2022

2021

2020

2019

2018

2017

2016

2015

2014

2013

2012

2011

2010

Users October 2020