Understanding QPS vs TPS: Key Metrics for System Performance
This article explains the definitions and differences between QPS and TPS, explores related concepts such as concurrency, throughput, PV, UV, DAU, MAU, and outlines practical methods for evaluating system performance and capacity planning.
1. QPS
QPS (Queries Per Second) measures the number of queries a server can respond to each second, representing the maximum throughput capacity.
2. TPS
TPS (Transactions Per Second) counts the number of complete transactions per second, where a transaction includes the client request, server processing, and response.
3. Difference between QPS and TPS
TPS counts each complete transaction, while QPS counts every individual request that may be part of a single transaction.
User requests the server
Server performs internal processing
Server returns the response to the user
For example, a page load may generate three server requests, resulting in one TPS but three QPS.
4. Concurrency
Concurrency (concurrent degree) is the number of requests the system can handle simultaneously, reflecting load capacity.
5. Throughput
Throughput is the number of requests processed per unit time; both QPS and TPS are common throughput metrics.
System Throughput Factors
The throughput depends on CPU consumption per request, external interfaces, I/O, etc. Higher CPU cost or slower I/O reduces throughput.
Key Parameters
QPS/TPS, concurrency, and response time.
Relationship
QPS (or TPS) = Concurrency / Average response time.
When either concurrency or response time reaches its limit, overall throughput cannot increase further and may even drop due to overload.
6. PV
PV (Page View) counts each page load or refresh.
7. UV
UV (Unique Visitor) counts distinct users within a day, deduplicated by unique identifier.
8. DAU
DAU (Daily Active Users) measures the number of users who actively use the product in a day.
9. MAU
MAU (Monthly Active Users) measures distinct active users per month.
10. System Throughput Evaluation
Designing a system requires considering CPU, I/O, external system latency, and estimating performance. Besides QPS and concurrency, daily PV is another dimension for capacity planning.
Typical method: identify the maximum TPS and daily PV, which have a relatively stable relationship, then use stress testing or experience to estimate the highest TPS and compute the maximum daily throughput.
11. Basic Concepts and Formulas for Software Performance Testing
Performance testing should focus on response time, resource usage, scalability, maximum concurrent users, bottlenecks, and 24/7 availability.
From a developer’s perspective, also consider architecture, database design, code efficiency, memory usage, thread synchronization, and resource contention.
Signed-in readers can open the original source through BestHub's protected redirect.
This article has been distilled and summarized from source material, then republished for learning and reference. If you believe it infringes your rights, please contactand we will review it promptly.
MaGe Linux Operations
Founded in 2009, MaGe Education is a top Chinese high‑end IT training brand. Its graduates earn 12K+ RMB salaries, and the school has trained tens of thousands of students. It offers high‑pay courses in Linux cloud operations, Python full‑stack, automation, data analysis, AI, and Go high‑concurrency architecture. Thanks to quality courses and a solid reputation, it has talent partnerships with numerous internet firms.
How this landed with the community
Was this worth your time?
0 Comments
Thoughtful readers leave field notes, pushback, and hard-won operational detail here.