Dear all, I was running some tests with the latest cp2k version as I wanted to try out the new implementations for the dispersion within DFTB. During these test I found out that the DFTB calculations in general were slower when compared to the 9.1 version I typically use. Some more testing showed that this was not a general issue, since regular DFT (BLYP) and the semi-empirical PM6 method had no slowdown. I did this testing on the same system and installed cp2k with the same flags ./install_cp2k_toolchain.sh --with-sirius=no --with-spla=no --with-elpa=no --with-plumed=install Additionally the input files are exactly the same. In the last tests I added a line to change images to infinite as the default setting was changed between the versions, but this had no impact as far as I know.<div>&DBCSR AVG_ELEMENTS_IMAGES -1 &END DBCSR I looked a bit into the outputfile and the timings it gives and it seems like the time loss is due to calls to rebuild_ks_matrix (and subsequently to build_dftb_ks_matrix), but I have no idea what I can do about this. Does anyone know what I can do? Or what is wrong? here is a link to google drive with all the files I used to do the calculations https://drive.google.com/drive/folders/1rUq-CwZygGr1GYs9pdMvf98r9YRa0Xjg?usp=sharing (both input and output) Kind regards, Roel v/d Ven </div> -- You received this message because you are subscribed to the Google Groups "cp2k" group. To unsubscribe from this group and stop receiving emails from it, send an email to <a href="mailto:cp2k+unsubscribe@googlegroups.com">cp2k+unsubscribe@googlegroups.com</a>. To view this discussion on the web visit <a href="https://groups.google.com/d/msgid/cp2k/61a4ae93-20f5-4e69-940a-36aa4390ced8n%40googlegroups.com?utm_medium=email&utm_source=footer">https://groups.google.com/d/msgid/cp2k/61a4ae93-20f5-4e69-940a-36aa4390ced8n%40googlegroups.com</a>.