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A comment on Do we really need swap on modern systems?. Parent comment

Re:Do we really need swap on modern systems? by Retric on Thursday February 23, 2017 @12:41PM (#13715852)
With SSD's disk is not that slow.
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Re:Do we really need swap on modern systems? by SapphireSun on Thursday February 23, 2017 @12:44PM (#13715882)
SSDs are only ~4x faster than magnetic last I checked. If RAM is 100ns per access, and hd access is down from say, 1ms to 0.25ms, that's still a huge huge gap. 4x isn't even an order of magnitude.

EDIT: see comment below for more accurate numbers.

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Re:Do we really need swap on modern systems? by snowwindwaves on Thursday February 23, 2017 @12:48PM (#13715930)
From the article:

>A typical reference to RAM is in the area of 100ns, accessing data on a SSD 150μs (so 1500 times of the RAM) and accessing data on a rotating disk 10ms (so 100.000 times the RAM.

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Re:Do we really need swap on modern systems? by xinyhn on Thursday February 23, 2017 @01:32PM (#13716388)
reminded me of this...

Latency Numbers Every Programmer Should Know

https://gist.github.com/jboner/2841832

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Re:Do we really need swap on modern systems? by SapphireSun on Thursday February 23, 2017 @12:51PM (#13715952)
Thank you for the correction. I should have read more carefully. Still, we're talking 3 orders of magnitude for SSD vs RAM.
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