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Testing / Apache JMeter Interview questions

How does the CSV Data Set Config distribute data across threads?

By default, each thread reads through the CSV file independently in sequence - if configured to share the file across all threads, every thread pulls the next available row from one shared cursor, so no two threads (across the whole test, not just one thread group) get the same row at the same moment.

The "Sharing mode" setting controls this behavior explicitly: options typically include sharing across all threads, sharing only within the current thread group, or giving each thread its own independent copy of the file to read through on its own.

What happens when a thread reaches the end of the file also matters and is separately configurable - by default, it recycles back to the start of the file, but this can be disabled if a test specifically needs every row consumed exactly once with no repeats, such as a test simulating unique account creation.

The 'Sharing mode' setting controls:
By default, when a thread reaches the end of the CSV file, it:

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