Microsoft Sharepoint Products and Technologies Resource Kit eBook

Chapter 10: Performance Monitoring in Microsoft Office SharePoint Portal Server 2003 241
Separating the Effects of Searching from Other Front-End Traffic When deciding
to scale out front-end Web/search servers, you must determine how much of the
CPU load is the result of search operations. As a rule of thumb, when the query rate
counter exceeds the indicated threshold and search operations are consuming about
40 to 50 percent of the overall server capacity, you should consider scaling out to a
large server farm. If the query rate is below the threshold but percent processor time
is exceeding the threshold, front-end Web traffic is bringing the server to capacity
and you should consider adding an additional front-end Web/search server to the
medium server farm.
Be sure to take into consideration the impact of extensive front-end traffic to
Windows SharePoint Services sites. If some of your Windows SharePoint Services
sites are generating significant front-end traffic, you might want to scale out one or
more of those sites to a separate server farm, as discussed in the “Dedicated Windows
SharePoint Services Server Farm” section later in this chapter.
Other Factors That Influence Search Performance Keep in mind that other factors
can cause heavy search loads—for example, a large content index (which can
slow down search performance) or heavy search query executions against a single
portal in a shared services farm. Make sure that user expectations for search performance
are realistic for your environment. Your customer’s requirements for search
response times, including commitments to service-level objectives that define specific
response times for searches, can necessitate adding a server before the thresholds
have been exceeded.
Dedicated Search Servers—Large Server Farm
Table 10-4 lists the most important counters for evaluating the performance of a dedicated
search server in a large server farm.
Table 10-4 Performance Counters for Dedicated Search Servers—Large Server Farm
Object Counter Threshold Description
Processor Percent processor
time_total
80 to 85 percent averaged
over three intervals.
The total percentage of processor
usage for a server.
Search Query rate 20 per second. The number of queries posted to
the server per second. Keep in
mind this counter should be
watched on the dedicated search
servers.
Search Succeeded
queries
This counter should be used
mostly for troubleshooting
search problems.
The number of queries that produce
successful searches; monitor
this counter along with the failed
queries counter if you need to
troubleshoot search problems.