JMeter Training

SSL Performance

Peter Lin

Jmeter Committer

SSL Basics

Mixing HTTPS with HTTP can create potential security risks

When is software HTTPS appropriate?

Hardware options for HTTPS/SSL acceleration

SSL impact on network bandwidth

If a page doesn't need to be secure don't encrypt it

Benchmark setup

The setup

Sun JDK 1.4.1 Server, JSSE 1.0.2

Pentium II 450 MHz with 128 MB RAM

RedHat Linux 7.3 (kernel 2.4.18)

RedHat Linux 7.3 (kernel 2.4.18)

~16Kb of data

simple servlet

package example;

import java.io.*;

import javax.servlet.*;

import javax.servlet.http.*;

public class ExampleServlet extends HttpServlet {

public void doGet(HttpServletRequest request,

HttpServletResponse response)

throws IOException, ServletException

{

PrintWriter out = response.getWriter();

for (int i = 0; i < 256; i++) {

out.write(" blah");

}

}

}

SSL without keepalive

Benchmarks by Remy Maucherat

With keepalive

Benchmarks by Remy Maucherat

What do the number mean?

Using keepalive results in 18x difference

Without keepalive 12 versus 229 with keepalive

Translating to real world performance

Calculate the average number of requests per page

Use half the maximum requests per second

Divide the maximum requests per second by average requests per page

What is the impact?

Consumes all the CPU cycles

Increases heat generated by the CPU

Results in instability

Real world performance

The setup

500Mhz pentium III

Windows NT

ASP + javascript

ODBC

Sybase ASE 10.1

512Gb RAM

100Mb ethernet

2 T1 lines

Average requests per checkout page 4

Maximum concurrent checkout 8 per system

Above the maximum, the systems would crash

Faster hardware

How does the software scale with better hardware?

2Ghz CPU can handle roughly 4x the concurrent load 20-25

Scalability is linear with respect to the number of CPU's and processor speed

Do the same limitations still apply?

Hardware acceleration will see the same gains as CPU speeds increase

A single SSL enabled router can service a cluster of machines

Is hardware acceleration still recommended?

Yes, hardware acceleration lets your servers focus on application process

SSL routers generate less heat and run more efficiently

Conclusion

Software SSL should be used as a last resort

Hardware acceleration is affordable today

Hardware acceleration improves the reliability of the servers and efficiency of the applications

peter lin

2005-06-18T21:41:01