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
- WebSphere Application Server v8.0 and and v7.0.0.15
- Lightweight Directory Access Protocol (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 WebSphere Application Server 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 WebSphere Application Server 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
Table 1. 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% |