Shige's Research Blog

Monday, December 03, 2018

The new 4.19 kernel is causing trouble

A "kworker" process is hogging my CPU. I have to go back to 4.18 kernel to resolve this issue.

Thursday, November 29, 2018

Saturday, November 24, 2018

Friday, November 02, 2018

Installing VMware workstation 15 on Manjaro

A few things to notice:

  1. Need to install Linux header files;
  2. Consult the pinned comments here.
A few useful commands:
  • sudo modprobe -a vmw_vmci vmmon
  • sudo vmware-modconfig --console --install-all
  • sudo systemctl enable vmware-networks
  • sudo systemctl start vmware-networks

Thursday, October 18, 2018

Zapcc with Rstan

I use the brms package, which uses the standard R formula syntax to generate Stan code, which gets translated into C++ code by rstan, get compiled and executed. In this process, a optimized C++ compiler can make a big difference.

Here I ran the brms sample code for the spatial simultaneous autoregressive (SAR) sample code using clang++ and zapcc and benchmared the performance (three times):

clang++: 66.89 (lagsar), 49.02 (errorsar)
zapcc: 56.80 (lagsar), 18.43 (errorsar)

Such a performance boost can be achieved by simply switching a compiler!

Saturday, October 13, 2018

Wednesday, July 04, 2018


Data science toolkit for Arch and Arch-based system here.