15 Performance questions from the Redis bank, written for Indian campus drives and tech interviews. Every question has a verified answer and an AI-tutor explanation on placd.
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A.a non-blocking way to walk the keyspace incrementally in small batches instead of scanning everything in one blocking call
B.an operation whose cost stays fixed regardless of dataset size, such as fetching or setting a single value by key
C.a command like fetching every member of a huge collection whose cost grows with element count and can stall the event loop
D.processing commands one at a time on a single core via an event loop, which removes the need for locks on data access
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2. Which term means: "processing commands one at a time on a single core via an event loop, which removes the need for locks on data access"?
Junior
A.Single-threaded execution
B.Pipelining
C.Cursor-based iteration
D.Constant-time command
Answer + AI explanation with Pro
3. Which statement is correct?
Junior
A.Single-threaded execution — processing commands one at a time on a single core via an event loop, which removes the need for locks on data access
B.Single-threaded execution — an operation whose cost stays fixed regardless of dataset size, such as fetching or setting a single value by key
C.Single-threaded execution — sending many commands in one batch without waiting for each reply, slashing round-trip latency over the network
D.Single-threaded execution — a non-blocking way to walk the keyspace incrementally in small batches instead of scanning everything in one blocking call
Answer + AI explanation with Pro
4. What is Pipelining?
Mid
A.sending many commands in one batch without waiting for each reply, slashing round-trip latency over the network
B.processing commands one at a time on a single core via an event loop, which removes the need for locks on data access
C.an operation whose cost stays fixed regardless of dataset size, such as fetching or setting a single value by key
D.a non-blocking way to walk the keyspace incrementally in small batches instead of scanning everything in one blocking call
Answer + AI explanation with Pro
5. Which term means: "sending many commands in one batch without waiting for each reply, slashing round-trip latency over the network"?
Mid
A.Cursor-based iteration
B.Pipelining
C.Single-threaded execution
D.Linear-time hazard
Answer + AI explanation with Pro
6. Which statement is correct?
Mid
A.Pipelining — a command like fetching every member of a huge collection whose cost grows with element count and can stall the event loop
B.Pipelining — an operation whose cost stays fixed regardless of dataset size, such as fetching or setting a single value by key
C.Pipelining — sending many commands in one batch without waiting for each reply, slashing round-trip latency over the network
D.Pipelining — processing commands one at a time on a single core via an event loop, which removes the need for locks on data access
Answer + AI explanation with Pro
7. What is Constant-time command?
Mid
A.processing commands one at a time on a single core via an event loop, which removes the need for locks on data access
B.an operation whose cost stays fixed regardless of dataset size, such as fetching or setting a single value by key
C.sending many commands in one batch without waiting for each reply, slashing round-trip latency over the network
D.a command like fetching every member of a huge collection whose cost grows with element count and can stall the event loop
Answer + AI explanation with Pro
8. Which term means: "an operation whose cost stays fixed regardless of dataset size, such as fetching or setting a single value by key"?
Mid
A.Single-threaded execution
B.Constant-time command
C.Pipelining
D.Linear-time hazard
Answer + AI explanation with Pro
9. Which statement is correct?
Mid
A.Constant-time command — an operation whose cost stays fixed regardless of dataset size, such as fetching or setting a single value by key
B.Constant-time command — processing commands one at a time on a single core via an event loop, which removes the need for locks on data access
C.Constant-time command — a non-blocking way to walk the keyspace incrementally in small batches instead of scanning everything in one blocking call
D.Constant-time command — a command like fetching every member of a huge collection whose cost grows with element count and can stall the event loop
Answer + AI explanation with Pro
10. What is Linear-time hazard?
Senior
A.sending many commands in one batch without waiting for each reply, slashing round-trip latency over the network
B.a non-blocking way to walk the keyspace incrementally in small batches instead of scanning everything in one blocking call
C.processing commands one at a time on a single core via an event loop, which removes the need for locks on data access
D.a command like fetching every member of a huge collection whose cost grows with element count and can stall the event loop
Answer + AI explanation with Pro
11. Which term means: "a command like fetching every member of a huge collection whose cost grows with element count and can stall the event loop"?
Senior
A.Constant-time command
B.Pipelining
C.Cursor-based iteration
D.Linear-time hazard
Answer + AI explanation with Pro
12. Which statement is correct?
Senior
A.Linear-time hazard — sending many commands in one batch without waiting for each reply, slashing round-trip latency over the network
B.Linear-time hazard — processing commands one at a time on a single core via an event loop, which removes the need for locks on data access
C.Linear-time hazard — a non-blocking way to walk the keyspace incrementally in small batches instead of scanning everything in one blocking call
D.Linear-time hazard — a command like fetching every member of a huge collection whose cost grows with element count and can stall the event loop
Answer + AI explanation with Pro
13. What is Cursor-based iteration?
Senior
A.a non-blocking way to walk the keyspace incrementally in small batches instead of scanning everything in one blocking call
B.an operation whose cost stays fixed regardless of dataset size, such as fetching or setting a single value by key
C.processing commands one at a time on a single core via an event loop, which removes the need for locks on data access
D.sending many commands in one batch without waiting for each reply, slashing round-trip latency over the network
Answer + AI explanation with Pro
14. Which term means: "a non-blocking way to walk the keyspace incrementally in small batches instead of scanning everything in one blocking call"?
Senior
A.Single-threaded execution
B.Constant-time command
C.Linear-time hazard
D.Cursor-based iteration
Answer + AI explanation with Pro
15. Which statement is correct?
Senior
A.Cursor-based iteration — a command like fetching every member of a huge collection whose cost grows with element count and can stall the event loop
B.Cursor-based iteration — processing commands one at a time on a single core via an event loop, which removes the need for locks on data access
C.Cursor-based iteration — an operation whose cost stays fixed regardless of dataset size, such as fetching or setting a single value by key
D.Cursor-based iteration — a non-blocking way to walk the keyspace incrementally in small batches instead of scanning everything in one blocking call
Answer + AI explanation with Pro
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