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colin-scott / interactive_latencies

Jeff Dean's latency numbers plotted over time
MIT License
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some questions about the data #17

Open cighao opened 4 years ago

cighao commented 4 years ago

Hi. It's a very nice website. But I have some questions about the data. On the website, "read 1000,000 bytes sequentially from memory is 3us", so the memory bandwidth should be 1MB/3us = 333GB/s. "read 1000,000 bytes sequentially from SSD is 49us", so the SSD bandwidth should be 1MB/49us = 20GB/s. "read 1000,000 bytes sequentially from disk is 825us", so the disk bandwidth should be 1MB/815us = 1.2GB/s. From my point of view, these data are much bigger than the real products' performance.

RemiTorracinta commented 3 years ago

It looks like the numbers are currently projections from 2012???

Here are some reasonable bandwidth numbers: https://www.forrestthewoods.com/blog/memory-bandwidth-napkin-math/

colin-scott commented 3 years ago

That's correct, I created this in 2012 ;-)

Happy to accept pull requests for updated models