Linux Performance Tuning - Comparing HP-UX

[MSwift]

Certain things are best understood while comparing a similar command structure. I have a large HP-UX background and i have done several performance reviews on HP-UX servers. For a server having a performance issues (like disk i/o, SAN performance issues, CPU, memory, memory leaks, kernel settings etc..For example i would login to a server and take a look at sar -v (inodes, nfiles, nproc etc), i would do a sar -b (look at rcache, wcache), max_queue_depth setttings for SCSI, ipcl, run down a kmtune/sysdef or kctune and note the settings(maxdsize, maxssize [for ulimit issues] run UNIX95 with ps for high CPU processes, memory etc, ..and much more..like /var/tomstones..savecore..VFP messages..GSP level..sysrev..etc etc..Since i have moved into RHEL(RHEL5 mainly) i wanted to know what are the typical performance parameters i have to know to be as familiar i was in HP-UX. Could someone give me a headstart for this effort..

Thanks

Mike.

[~sesh]

The performance parameters that you need to look out for in Linux are more or less the same as HP-UX. I'm mentioning the major ones below:

The /proc directory contains all of the systems hardware details.

For processor and process details - top, uptime, mpstat, ps commands can be used.
Memory statistics - top, vmstat, free commands.

Disk statistics - vmstat, iostat, hdparm

Network statistics - netstat, ip, ethtool.

Kernel parameters - /boot/config--

Hope this helps to some extent.

[Huc_1]

Having a look into at what is under /proc
will help you find out lots about hardware

lsof is also helpful to find what ressources are being used.

Sar is probably already on the system if not
yum install it.

# yum install sysstat

for more info on sar look at maintainer page at

http://sebastien.godard.pagesperso-orange.fr/

sysctl let you have a look and configure kernel parameters at runtime /etc/sysctl.conf is for permanent (survive reboot parameters )

good place to start fishing for informations is from /var/log/messages /var/log/security /var/log/* and dmessg

check these tools with man ipcs, netstat, iptstate, iptraf, tcpdump and or 'yum info whatever' to find out more if they are not on your system.

ps command can also be used with UNIX95 if you set the right variable check man ps for more on this.(this is maybe how it is done on HP-UX)

and a lot more but this should get you on the way.

Enjoy life.

Jean-Pierre Huc