BW_UNIX(8)

bw_unix(8) 💖

okay bestie, this is the LMBENCH manual page for bw_unix, and it is literally about how fast a UNIX pipe can move bytes. section 8, system-adjacent chaos, we love her 💅

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✨ NAME ✨

bw_unix — UNIX pipe bandwidth 🫶

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🦋 SYNOPSIS 🦋

bw_unix [ -P <parallelism> ] [ -W <warmups> ] [ -N <repetitions> ] size

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🌸 DESCRIPTION 🌸

so bw_unix creates a pipe and then forks a child process that just... keeps writing data into that pipe as fast as it possibly can 🔥. main character energy fr.

the benchmark then measures how fast the parent process can read the data, in size-byte chunks, straight out of the pipe. that's it. that's the whole vibe.

and here's the iconic part: nothing is done with the data — not in the parent (the reader) and not in the child (the writer). neither process. they just move bytes and feel nothing. 💀

the size spec can end with k or m to mean kilobytes (* 1024) or megabytes (* 1024 * 1024). lowkey convenient, no cap.

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👑 OUTPUT 👑

the output format is literally "%0.2f %.2f\n", and the two numbers are megabytes and megabytes_per_second. like, for example:

8.00 25.33

slay. that's the whole output. two little numbers, one big flex ✨

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🎀 MEMORY UTILIZATION 🎀

this benchmark should move approximately the reported amount of memory. so like, the number is not lying to you, bestie, the memory really did go on that journey 🧚

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🌈 ACKNOWLEDGEMENT 🌈

funding for the development of this tool was provided by Sun Microsystems Computer Corporation. we stan a sponsor 💜

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🔥 SEE ALSO 🔥

lmbench(8).

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🍓 AUTHOR 🍓

Carl Staelin and Larry McVoy

and fr fr, comments, suggestions, and bug reports are always welcome — they literally said so 🫶

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okay that's the whole page, go forth and measure some pipes, i believe in you 💅

©1994–2000 Larry McVoy and Carl... — and yeah the date field is literally sitting there as $Date$ in the footer, iconic honestly — signed off from BW_UNIX(8), LMBENCH edition 🌸