Fix Lzbench empty metrics on ARM64 due to stdout buffering#664
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Fix Lzbench empty metrics on ARM64 due to stdout buffering#664
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When lzbench runs with -o4 (CSV format) and stdout is redirected to a file, the C library uses full-buffering (4-8KB blocks). If the process is killed before completion (e.g., by VC timeout), the unflushed buffer is lost and results-summary.csv is empty — especially on ARM64 where lzbench runs slower and never reaches the flush threshold. Adding stdbuf -oL forces line-buffered output so each CSV row is flushed to disk immediately, ensuring partial results survive process termination. Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
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When lzbench runs with -o4 (CSV format) and stdout is redirected to a file, the C library uses full-buffering (4-8KB blocks). If the process is killed before completion (e.g., by VC timeout), the unflushed buffer is lost and results-summary.csv is empty — especially on ARM64 where lzbench runs slower and never reaches the flush threshold.
Adding stdbuf -oL forces line-buffered output so each CSV row is flushed to disk immediately, ensuring partial results survive process termination.