CERN Useful Linux Commands Buffer Cache/Block IO Activity vmstat -n 1 ODevice Activity iostat -x 1 dstat oTask Overview (proc interface) top,htop,iftop,iotop 。。。 CERN） CSC 2018 Data Technology Exercises
CSC 2018 Data Technology Exercises Useful Linux Commands Buffer Cache/Block IO Activity vmstat -n 1 Device Activity iostat -x 1 dstat Task Overview (proc interface) top, htop, iftop, iotop
CERN Useful Linyx Commands oTrace system commands of a program strace <program> [program args -f follow forks -c count sys calls -ttt show high time resolution man strace CERN） CSC 2018 Data Technology Exercises
CSC 2018 Data Technology Exercises Useful Linux Commands Trace system commands of a program strace <program> [program args] -f follow forks -c count sys calls -ttt show high time resolution → man strace !
CERN Useful Linyx Commands oFlush dirty pages as user or root sync oClean page cache >as user: write a new file bigger than the memory size as root echo 3 /proc/sys/vm/drop caches CERN） CSC 2018 Data Technology Exercises
CSC 2018 Data Technology Exercises Useful Linux Commands Flush dirty pages as user or root sync Clean page cache → as user: write a new file bigger than the memory size → as root echo 3 > /proc/sys/vm/drop_caches
CERN lO baseline measurements Before we debug an application let's have a look at the baseline performance of our working environment .. CERN） CSC 2018 Data Technology Exercises
CSC 2018 Data Technology Exercises IO baseline measurements • Before we debug an application let’s have a look at the baseline performance of our working environment …
CERN Linux zero/null devices dd if=/dev/zero of=/dev/null bs=1M count=16000 CERN) CSC 2018 Data Technology Exercises
CSC 2018 Data Technology Exercises dd if=/dev/zero of=/dev/null bs=1M count=16000 Linux zero/null devices