PSR

  • Performance, Stability, Reliability with Scalability
  • Tools:
    • Jmeter

p95, p99, p999 latency

  • p99 is the 99th percentile. It means that 99% of the requests should be faster than the given latency. In other words only 1% of the requests are allowed to be slower.
  • Example:
    • Here p95 is 6s and p99 is 7s
LatencyNumber of requestsCumulative frequency
1s55
2s510
3s1020
4s4060
5s2080
6s1595
7s499
8s1100

HA and DR (High Availability and Disaster Recovery)

  • High Availability (HA) — refers to a system or component that is continuously operational for a desirably long period.
  • Disaster Recovery (DR) — involves a set of policies and procedures to enable the recovery or continuation of vital infrastructure and systems following a natural or human-induced disaster.

Required HA and DR infrastructure elements

  • Distributed Approach
  • Load balancing
  • Databases
    • synchronous replication
    • asynchronous replication

TPS (Transactions per second)

  • TPS represents the number of transactions that can be processed by a system per second.
  • In some cases transaction can stand for a “single request” but more often it is a series of requests representing “a piece of business logic” like:
    • User opens a site
    • User opens login page
    • User performs login

RPS (Request per second)

  • Request per second is the number of HTTP requests processed by a web server or web application in a second

Load Testing

  • Applying simulated load to a system and measuring the overall impact on the system

Performance Testing

  • Monitoring and measuring the performance of a system regardless of load

Stress Testing

  • Increase the simulated load on a system to a point where the system fails