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0 pointsbottled_poe5mo ago0 comments

What’s the I/O throughput of /dev/null ?

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Single client, I'm getting ~5GB/s, both on an 8-year-old intel server, and on my M1 ARM chip.

However with a single server, it doesn't perfectly linearly scale with multiple clients. I'm getting

1 client: 5GB/s

2 clients: 8GB/s

3 client: 8.7GB/s

I'm easily reaching 30GB/s with a single client:

    dd if=/dev/zero of=/dev/null bs=1M status=progress

A second dd process hits the same speed.

My artisanal architecture design uses writes with a few characters and uses unix pipes:

    yes | pv > /dev/null

I hope that in my next rewrite I can advance to larger block sizes.

What's the best hardware for running a /dev/null instance for production?

How did you measure this? Do you know that /dev/null is the limiting factor, or could it be the data source that is limiting?

You start dealing with Heisen-throughput at that point, it goes as high as you can measure.

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