Express (Distributed operating systems), v8.0 > Secure applications and their environment > Authenticate users > Select a registry or repository > Manage realms in a federated repository > Virtual member manager > Tune
Performance benchmark for virtual member manager
This document presents performance benchmarking results for virtual member manager 8.0 startup time and memory footprint as compared to the prior version.
Hardware and Software specifications
These performance benchmarking results were obtained when tested under IBM lab conditions on a standalone system with the following hardware and software specifications.
Software specifications
A system with the following software specifications was used to run the performance tests:
- Operating system: Red Hat Enterprise Linux Server release 5.5
- WAS v8.0 and and v7.0.0.15
- LDAP configured on both versions: IBM Tivoli Directory Server 6.2 installed on a system with Windows 2008R2 64-bit operating system
- Virtual member manager (federated repositories) configured with File and LDAP repositories
Hardware specifications
The system on which WAS was installed and used to run the virtual member manager performance tests for measuring startup time and memory footprint had the following hardware specifications:
- Processors: 8 Intel processors having cache size of 1024 KB each
- Processor clock speed: 1590.450 MHz
- CPU type: 32-bit
- Memory size (RAM): 8129028 KB
- Hardware platform: i386
- Hard disk specifications:
- 6 disks of 36.4 GB each with the following properties:
- 255 heads, 63 sectors/track, 4425 cylinders
- Units = cylinders of 16065 * 512 = 8225280 bytes
The system on which IBM Tivoli Directory Server was installed had the following hardware specifications:
- Processors: 2
- Processor clock speed: 3.00 GHz
- CPU type: 64-bit
- Memory size (RAM): 4 GB
- Hardware platform: i386
- Hard disk: 140 GB
Startup time
The time taken by virtual member manager to start during WAS startup is given here.
The average startup time of virtual member manager over 1-10 iterations measured in milliseconds is:
- 4842.1 for v8.0
- 6799.2 for v7.0.0.15
This shows an approximate improvement of 28% in v8.0 as compared to v7.0.0.15.
Memory footprint
There are three aspects of memory footprint considered here:
Live bytes
When objects are created from a class, the instance objects are stored on the java heap, which is live bytes.
The following results show the live bytes, which is memory still in use (memory on Java heap) for virtual member manager in number of bytes:
- 1121408 for v8.0
- 1259136 for v7.0.0.15
Class memory
Every class requires some memory to store the code for its methods and other stuff. These are ROM bytes or class memory. ROM bytes are not stored on the heap; they are in a class memory section of the JVM.
The following results show the class memory used by virtual member manager in number of bytes:
- 1188472 for v8.0
- 1371616 for v7.0.0.15
Native memory
Native memory refers to the system's memory. If the Java code has any native code (DLL, LIB), they are loaded in the native memory. Virtual member manager does not use any native memory.
Summary
Performance benchmarking results for virtual member manager 8.0
v8.0 v.7.0.0.15 Unit of measurement % Improvement Average startup time 4842.1 6799.2 milliseconds 28.78% Live bytes (Java heap, memory in use) 1121408 1259136 bytes 10.93% Class memory (ROM bytes) 1188472 1371616 bytes 13.35%
Parent topic: Tune