Atop – A top System and Process Monitor
Just learned about this useful tool called atop. Better than top and just as useful as vmstat; atop will track processes as they grow and shrink memory. Very handy tool to determine what is going on a system and where to begin when looking for places to tune. Found this interesting and highly recommended paper discussing the tool using a case study of a process that has gone memory bound on the atop website.
To install on Centos. Choose one of the following commands depending on 32 or 64 bit Centos:
# rpm -Uvh http://download.fedora.redhat.com/pub/epel/5/i386/epel-release-5-4.noarch.rpm or # rpm -Uvh http://download.fedora.redhat.com/pub/epel/5/x86_64/epel-release-5-4.noarch.rpm followed by: # yum install atop
Note: Don’t forget to enable the repository if it is disabled.
Once installed, you can type the following:
# atop
which will yield the following output:
ATOP - mimir 2011/01/27 18:23:00 2858101 seconds elapsed
PRC | sys 123h31m | user 80h32m | #proc 336 | #zombie 0 | #exit 0 |
CPU | sys 13% | user 13% | irq 0% | idle 771% | wait 3% |
cpu | sys 3% | user 2% | irq 0% | idle 95% | cpu000 w 0% |
cpu | sys 2% | user 2% | irq 0% | idle 95% | cpu001 w 0% |
cpu | sys 2% | user 1% | irq 0% | idle 95% | cpu005 w 2% |
cpu | sys 1% | user 1% | irq 0% | idle 97% | cpu006 w 0% |
cpu | sys 1% | user 1% | irq 0% | idle 98% | cpu003 w 0% |
cpu | sys 1% | user 2% | irq 0% | idle 97% | cpu002 w 0% |
cpu | sys 1% | user 1% | irq 0% | idle 98% | cpu007 w 0% |
cpu | sys 2% | user 2% | irq 0% | idle 96% | cpu004 w 0% |
CPL | avg1 0.00 | avg5 0.02 | avg15 0.04 | csw 179951e5 | intr 80499e5 |
MEM | tot 11.8G | free 405.0M | cache 7.0G | buff 208.5M | slab 432.8M |
SWP | tot 23.4G | free 23.1G | | vmcom 8.6G | vmlim 29.3G |
PAG | scan 5625e5 | stall 0 | | swin 1120890 | swout 1220e3 |
DSK | sdb | busy 5% | read 25104e3 | write 8528e3 | avio 4 ms |
DSK | sdc | busy 4% | read 26837e3 | write 8501e3 | avio 3 ms |
DSK | sda | busy 4% | read 26190e3 | write 8600e3 | avio 3 ms |
DSK | sdd | busy 4% | read 26680e3 | write 8400e3 | avio 3 ms |
NET | transport | tcpi 58338e4 | tcpo 22045e4 | udpi 438593 | udpo 160644 |
NET | network | ipi 584080e3 | ipo 220687e3 | ipfrw 0 | deliv 5840e5 |
NET | eth0 0% | pcki 59401e4 | pcko 22900e4 | si 1778 Kbps | so 2093 Kbps |
NET | lo ---- | pcki 30472 | pcko 30472 | si 0 Kbps | so 0 Kbps |
NET | virbr0 ---- | pcki 0 | pcko 9199 | si 0 Kbps | so 0 Kbps |
*** system and process activity since boot ***
PID SYSCPU USRCPU VGROW RGROW RDDSK WRDSK ST EXC S CPU CMD 1/34
3397 83h44m 46h33m 2.9G 1.2G 147.8G 1054.6G N- - S 16% VirtualBox
5803 736m59s 19h37m 2.6G 244.5M 212.3M 4.4G N- - S 4% chrome
2232 771m40s 101m04s 209.5M 34536K 157.6M 3324K N- - S 2% Xorg
2527 214m08s 201m18s 566.7M 41900K 195.5M 12K N- - S 1% pulseaudio
495 279m49s 0.00s 0K 0K 0K 0K N- - S 1% md1_raid5
2749 22m30s 123m30s 964.5M 43936K 24420K 1436K N- - S 0% chrome
2514 35m03s 104m01s 1.5G 349.3M 2.3G 19.4G N- - S 0% chrome
1462 28m16s 27m14s 242.7M 5024K 17788K 12.5G N- - S 0% rsyslogd
2594 2m29s 41m53s 1.4G 200.5M 140.7M 256K N- - S 0% chrome
3365 24m51s 19m27s 815.3M 3432K 407.0M 103.0M N- - S 0% VBoxSVC
