OpenWest 2014/Linux Performance Tools

by Ed Felt - DBA/Developer at LDS Church

Keep it simple ... at least at first

No Mockumentation - Document well, even over document

Recommended course - Linux Foundation - Linux Performance Tools (LF426) - ~$3,000

• https://training.linuxfoundation.org/linux-courses/system-administration-training/linux-performance-tuning

Track changes as you test

Human memory sucks - keep personal notes (journaling)

Keep focused on one variable at a time (Exception: fix it now emergency fire!) - most of us think linearly

Examples:

• ngrep to troubleshoot Segmentation Fault that doesn't make it to the logs
• actime0=0 # NFS (?kill it/keep it?)

Stress testing is NOT base-lining/profiling or even troubleshooting

/proc - TLDP describes it as "window" in to kernel and processes

PIDS:

• /proc/PID/cmdline
• /proc/PID/cwd
• /proc/PID/environ
• /proc/PID/exe
• ps

CPU:

• /proc/cpuinfo
• top

Memory:

• /proc/meminfo
• free

Netstat:

• /proc/net/netstat
• netstat

Logs:

• /var/log/messages
• /var/log/[application]

Write your own:

• BASH
• Perl
• Python

Tools:

• hdparm -tT /dev/....
• top
• sar (sysstat)
• collectl
• mlmon

Other tools:

• watch
• tail
• strace
• iostat
• vmstat
• nmon
• iptraf
• lsof
• htop