alt Hacker NewsSequential reads are faster for SSDs. As long as defragmentation is reducing the chance of doing a random read, it is beneficial.
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socalgal2 • today at 5:39 AM
OH! TIL! Apparently
contiguous fragmented
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PCIe 4.0 NVMe Read Speed ~5,000 – 7,000 MB/s ~80 – 250 MB/s
SATA 3.0 SSD Read Speed ~500 – 550 MB/s ~30 – 60 MB/s
> You are giving up virtually 0% to 3% of real-world performance. In daily development, media editing, and standard system use, defragmenting your SSD will yield no human-noticeable speedup.
__d • today at 4:33 AM
Is it possible to determine which sectors are physically sequential given remapping for wear-leveling?
Otherwise the claimed defragmentation here is not actually resulting in sequential data.
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Groxx • today at 4:50 AM
Prefetching applies to SSDs too, and that's generally sequential in some sense.
Don't want to wake you up from your Pakistani coma, but data is accessed differently on metal disc spinning 120 revolutions per second, and a NAND flash.
Defragmentation logic for HDD's doesn't work on SSD. For like 10+ years, all SSD's have T.R.I.M. technology to rearrange data themself for faster access, and for more consistent storing of new data.