Reducing Performance Monitoring Overhead
Performance monitoring uses system resources
that can affect the performance of a system as well as affect the data
being collected. To ensure that performance monitoring and analyzing do
not affect the machines being monitored themselves, you need to
decrease the impact of performance monitoring. Some steps can be taken
to ensure that performance-monitoring overhead is kept to a minimum on
the server being monitored to create as accurate of an analysis on a
system as possible:
• Use a remote server to monitor the
target server. Servers can actually be dedicated to monitoring several
remote servers. Although this might also lead to an increase in network
bandwidth, at least the monitoring and tracking of information do not
drastically degrade CPU or disk I/O as if the monitoring tool were
actually running on the server being monitored.
• Consider reducing the frequency of
the data collection interval because more frequent collection can
increase overhead on the server.
• Avoid using too many counters. Some
counters are costly in terms of taxing a server for system resources
and can increase system overhead. Monitoring several activities at one
time also becomes difficult.
• Use logs instead of
displaying graphs. The logs can then be imported into a database or
report. Logs can be saved on hard disks not being monitored or analyzed.
Important Objects to Monitor
The numbers of system and application
components, services, and threads to measure in Windows Server 2012 are
so extensive that it is impossible to monitor thousands of processor,
print queue, network, or storage usage statistics. Defining the roles a
server plays in a network environment helps to narrow down what needs
to be measured. Servers could be defined and categorized based on the
function of the server, such as application server, file and print
server, or services server such as DNS, domain controller, and so on.
Because servers perform different roles, and
hence have different functions, it makes sense to monitor the essential
performance objects. This helps prevent the server from being
overwhelmed from the monitoring of unnecessary objects for measurement
or analysis.
Overall, four major areas demand the most
concern: memory, processor, disk subsystem, and network infrastructure.
They all tie into any role the server plays.
The following list describes objects to monitor based on the roles played by the server:
• Active Directory Domain Services—Because
the DC provides authentication, stores the Active Directory database,
holds schema objects, and so on, it receives many requests. To be able
to process all these requests, it uses up a lot of CPU resources,
disks, memory, and network bandwidth. Consider monitoring memory, CPU,
system, network segment, network interface, and protocol objects such
as TCP, UDP, NBT, NetBIOS, and NetBEUI. Also worth monitoring are the
Active Directory NTDS service and site server LDAP service objects. DNS
and WINS also have applicable objects to be measured.
• File and print server—The
print servers that process intensive graphics jobs can utilize
extensive resources of system CPU cycles very quickly. The file server
takes up a lot of storage space. Monitor the PrintQueue object to track
print spooling data. Also monitor CPU, memory, network segment, and
logical and physical disks for both file and print data collection.
• Messaging collaboration server—A
messaging server such as an Exchange Server 2010 uses a lot of CPU,
disk, and memory resources. Monitor memory collection, cache,
processor, system, and logical and physical disks. Exchange objects are
added to the list of objects after Exchange is installed, such as
message queue length or name resolution response time.
• Web server—A web
server is usually far less disk intensive and more dependent on
processing performance or memory space to cache web pages and page
requests. Consider monitoring the cache, network interface, processor,
and memory usage.
• Database server—Database
servers such as Microsoft SQL Server 2008 can use a lot of CPU and disk
resources. Database servers can also use an extensive amount of memory
to cache tables and data, so RAM usage and query response times should
be monitored. Monitoring objects such as system, processor, logical
disk, and physical disk is helpful for overall system performance
operations.
