As mentioned in the accepted answer, GNU shuf supports simple random sampling (shuf -n) quite well. If sampling methods beyond those supported by shuf are needed, consider tsv-sample from eBay's TSV Utilities. It supports several additional sampling modes, including weighted random sampling, Bernoulli sampling, and distinct sampling. Performance is similar to GNU shuf (both are quite fast). Disclaimer: I am the author.

As mentioned in the accepted answer, GNU shuf supports simple random sampling (shuf -n) quite well. If sampling methods beyond those supported by shuf are needed, consider tsv-sample from eBay's TSV Utilities. It supports several additional sampling modes, including weighted random sampling, Bernoulli sampling, and distinct sampling. Performance is similar to GNU shuf (both are quite fast). Disclaimer: I am the author.

As mentioned in the accepted answer, GNU shuf supports simple random sampling (shuf -n) quite well. If sampling methods beyond those supported by shuf are needed, consider tsv-sample from eBay's TSV Utilities. It supports several additional sampling modes, including weighted random sampling, Bernoulli sampling, and distinct sampling. Performance is similar to GNU shuf. Disclaimer: I am the author.

As mentioned in the accepted answer, GNU shuf supports simple random sampling (shuf -n) quite well. If sampling methods beyond those supported by shuf are needed, consider tsv-sample from eBay's TSV Utilities. It supports several additional sampling modes, including weighted random sampling, Bernoulli sampling, and distinct sampling. Performance is similar to GNU shuf (both are quite fast). Disclaimer: I am the author.