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Comment by simlevesque | Hacker News Reader

I've had this with gen5 PCIe SSDs recently. My T710 is so fast it's hard to believe. But you need to have a lot of data to make it worth.

Example:

    > time du -sh .
    737G .
    ________________________
    Executed in   24.63 secs

And on my laptop that has a gen3, lower spec NVMe:

    > time du -sh .
    304G .
    ________________________
    Executed in   80.86 secs

It's almost 10 times faster. The CPU must have something to do with it too but they're both Ryzen 9.

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To me that reads 3x, not "almost 10x". The main differrence here is probably power. A desktop/server is happy to send 15W to the SSD and hundreds of watts to the CPU, while a laptop wants the SSD running in the ~1 watt range and the CPU in the 10s of watts range.

There's over twice as much content in the first test. It's around 3.8gb/s vs 30gb/s if you divide both folder size and both du durations. That makes it 7.9 times faster and I'm comfortable calling this "almost 10 times".

oops. I missed the size diff. that's a solid 8x. that's cool!

The total size isn't what matters in this case but rather the total number of files/directories that need to be traversed (and their file sizes summed).

I responded here, it's essentially the same content: https://news.ycombinator.com/item?id=46150030

I believe you, but your benchmark is not very useful. I get this on two 5400rpm 3T HDDs in a mirror:

    $ time du -sh .
    935G    .
                                                                                                                          
    real    0m1.154s

Simply because there's less than 20 directories and the files are large.

I should have been more clear: It's my http cache for my crawling jobs. Lots of files in many shapes.

My new setup: gen5 ssd in desktop:

    > time find . -type f | wc -l
    5645741
    ________________________
    Executed in    4.77 secs

My old setup, gen3 ssd in laptop:

    > time find . -type f | wc -l
    2944648
    ________________________
    Executed in   27.53 secs

Both are running pretty much non-stop, very slowly.

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