The performance monitoring tools provide a way of measuring system performance characteristics such as transaction throughput and processor usage.
Resource Management Facility (RMF)
This tool collects
information about activity for selected areas of the system. Information
is collected in the form of System Management Facility (SMF) records.
You can use the tool to measure processor and I/O activity in the CICS® Transaction Gateway address
space, and also, for example, to measure similar activity in the CICS server and WebSphere®. For more information see the 
z/OS® Resource
Management Facility (RMF™) Performance
Management Guide.
Request monitoring exits
These exits are applications written by independent software vendors that can be called at significant points in the request flow through the Gateway daemon and Gateway classes. Request monitoring exits are an important tool used when analyzing transaction flows during problem determination and performance tuning.
IBM Tivoli OMEGAMON XE for CICS
This tool monitors and manages CICS transactions and resources. IBM® Tivoli® OMEGAMON® XE for CICS quickly detects and isolates problems when they occur on CICS systems.
IBM Z Application Performance Management Connect (IBM Z APM Connect)
IBM Z APM Connect tracks CICS Transaction Gateway requests by providing request monitoring exits to report performance metrics.
Refer also to the performance and tuning documentation for WebSphere, TCP/IP, CICS Transaction Server for z/OS, and TXSeries and the documentation supplied with your operating system.
Information