ESXTOP Troubleshooting

ESXTOP Introduction One of the many jobs administrators are tasked with is that of performance monitoring to ensure that the environments we are responsible for are running as smoothly and as efficiently as possible. This fact remains true regardless of whether we are running in a physical or in a virtual environment. While the graphs displayed to us through the vSphere Client / vSphere Web Client do provide us some of that functionality the tool to most likely be used should we decide to involve !"ware technical support will be #S$TO%. #S$TO% is one of those commands not covered in the official !"ware &.' (nstall Configure and "anage course )it is mentioned in one slide* however #S$TO% )and it+s brother res,top* provide us with a way to view live performance data directly on the host using counters and percentages. -or those administrators familiar with inu, / 0($ #S$TO% is used the same way the TO% command is used. %ersonally ( believe that for performance troubleshooting #S$TO% gives us the best native tool to monitor resources such as C% memory disk and network usage. (n this document ( attempt to outline some of the more common options used with the #S$TO% command along with their description recommended thresholds and e,amples of problems that may signal a potential issue within our environment. Starting esxtop 1eing a command line tool we first need to determine how we are going to access that command line. 2epending on the method chosen the command used to invoke it may change somewhat. (f using SS3 or the #S$i shell we would log in and enter4 esxtop

(n the event we would prefer to use the downloadable vC( )vSphere Command ine (nterface* package or v"5 )vSphere "anagement 5ssistant* the command changes to4 resxtop --server

6egardless of the method used to access the tool the first screen encountered is the C% statistics )-igure '*. This screen is automatically refreshed every & seconds however the refresh rate can be changed by using +s+ to denote seconds and then the desired number of seconds between refreshes.  5s an e,ample e,ample the the following following command would set the pages pages refresh rate to refresh refresh every 7 seconds4 seconds4 s7

We can navigate to screens displaying other resources by using different keystrokes. 5lthough there are a multitude of available options the following are the most commonly used and therefore the ones (+ll focus on4 c 8 cpu m 8 memory n 8 network d 8 disk adapter  u 8 disk device )includes 0-S as of 9.: pdate ;* v 8 virtual machine disk activity CPU

-igure '. C% !iew )at rest*  5s previously mentioned the first screen defaults to the C% view which provides us valuable information in how the physical C% is being utili ' Win$%>; Win$%>7* each with a ?62@ time of less than one )'*. sing the chart below )Table '* we can surmise that no !" is currently waiting for a vC% and that all !"s are currently receiving the necessary C% resources reAuired to meet their demands.

View

Column

Threshold

Description

C%

?62@

':

The amount of time a C% is ready and waiting to e,ecute an instruction but can+t because it can+t get scheduled on to a %C%.

C%

?CST%

7

The amount of time a vS"% !" spent de> scheduled to try and eAualiJ;=J http4//communities.vmware.com/docs/2OC>&;9: http4//www.vmware.com/pdf/vsphere9/r9'/vspN9'NresourceNmgmt.pdf  !"world ;:'' > #S$TO% for 5dvanced sers !"world ;:'' > %erformance 1est %ractices and Troubleshooting