|
| ▲ | socalgal2 an hour ago | parent | next [-] |
| OH! TIL! Apparently contiguous fragmented
-------------------------------------------------------------------
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
Still, given SSDs have a lifespan and given few of my files are that large, I think I'm personally okay without defragmenting. Those numbers are impressive but, most of 10s of thousands of files are source code text files. Asking online what the real-world loss is from not defragmenting> 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 2 hours ago | parent | prev | next [-] |
| 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. |
| |
| ▲ | wtallis 2 hours ago | parent | next [-] | | You cannot directly inspect the degree of fragmentation, because it has less to do with being contiguous in the Logical Block Address (LBA) space and more to do with having been written at the same time. To properly defragment a file on a SSD, you pretty much need to sequentially re-write the whole file in one go, to a newly-allocated part of the drive's LBA space. | |
| ▲ | charcircuit 2 hours ago | parent | prev [-] | | >Otherwise the claimed defragmentation here is not actually resulting in sequential data. I haven't measured it but the SSD firmware should be able to look up where the next block is speculatively in order to be able to immediately start sending it if the host tries and read the next block (as opposed to a random one). |
|
|
| ▲ | Groxx 2 hours ago | parent | prev [-] |
| Prefetching applies to SSDs too, and that's generally sequential in some sense. |
