I'm showing 20-200ms longer on first run of the exec. Modified the test script a bit to show that it doesn't happen again if you modify the executable's contents.
    echo $'#!/bin/sh\necho Hello' > /tmp/test.sh && \
    chmod a+x /tmp/test.sh && \
    time /tmp/test.sh && \
    time /tmp/test.sh && \
    echo 'echo Hello2' >> /tmp/test.sh && \
    time /tmp/test.sh replies(1):