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Generic Tools to find root causes of problems
dmesg -Hw # Human readable, follow tail -f /var/log/syslog tail -f /var/log/syslog
Check RAM usage. Yes, it's always full, but space in “buff/cache” is free to use
free -m
Load can be CPU bound or Disc bound (or caused by network issues).
Load average ist not about instant CPU usage, it shows ow many processes are waiting to run
If the Load is rising constantly, probably there is a hanging process blocking the disc. Check for: - rsync - happens if the remote is down - sshfs - may not release a mount point, if the remote is down - munin - the disc free plugin hangs, when there are stale mounts - …
watch cat /proc/loadavg
top Cpu(s): 11.4%us, 29.6%sy, 0.0%ni, 58.3%id, .7%wa, 0.0%hi, 0.0%si, 0.0%st
IF “wa” I/O wait is high, the load is most probably Disc bound (or RAM)
iotop -oP iostat
This can really help!
ps -e v
This outputs the state of each process. Specially D is intereting (but also R):
D Marks a process in disk (or other short term, uninterruptible) wait. R Marks a runnable process …