You can try something like: TERM=vt100 top -b -n 1 This will set the TERM variable to execute with the “top” command. But your underlying problem is that your termcap database is incomplete or broken. I don’t have a Debian machine to look at, but on an Ubuntu box, the “dumb” termcap info is in … Read more
The best answer I can give you is “iowait is too high when it’s affecting performance.” Your “50% of the CPU’s time is spent in iowait” situation may be fine if you have lots of I/O and very little other work to do as long as the data is getting written out to disk “fast … Read more
A very good observation and we have run into this as well. Here’s what I found: Be careful measuring CPU usage from within an EC2 instance. It’s possible to see CPU usage well below 100%—and yet be completely maxed out. Trust me: been there, done that. (CloudWatch CPUUtilization, by the way, is measured from outside … Read more
I think this bug is your case. From what I see from the output, you have enough memory (note the cached 14 GB or so), no I/O issues, but you have xen-related processes running. This make me think it is a bug.
You could to something like this top -p `pgrep -d ‘,’ “java|tomcat|redis|mysql|mongo”` This gets pgrep to produce a comma separated list of pid’s that are passed to top -p
The “top” utility is in the “procps” package on RHEL/CentOS systems.
Your smem -tw output shows that your kernel is consuming over 9 GB of dynamic memory: danslimmon@bad-server:~$ smem -tw Area Used Cache Noncache firmware/hardware 0 0 0 kernel image 0 0 0 kernel dynamic memory 12857576 2887440 9970136 userspace memory 17661400 1272468 16388932 free memory 351592 351592 0 ———————————————————- 30870568 4511500 26359068 So, some kernel … Read more
The correct answer is: -U ‘!root’ (or -u ‘!root’ on some Ubuntus). This was introduced in top v3.2.9: man top for -U option: Prepending an exclamation point (‘!’) to the user id or name instructs top to display only processes with users not matching the one provided. Remember to put the exclamation mark and username … Read more
Running top in batch mode to report memory sizes periodically can be used to see who is using the memory when things go south. Runing sar in batch mode should give some good diagnostics on memory use, and related I/O. Running munin to monitor the system should give you a graph with good detail on … Read more
Well, in case you’re feeling brave: gdb -p 20788 then issue bt to see the stack-frame, for e. g. And BTW, there’s also ltrace to mention — try it as well. UPD.: well, ok, since now we have an idea that Apache is really running something, why wouldn’t ya look at mod_status output — Extended … Read more