reader50

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Everything posted by reader50

  1. When you save an updated file. Or the OS appends a log file. The change may be trivial from your perspective (perhaps only a few bits altered) but the SSD cannot erase/rewrite tiny spaces. Only the huge internal blocks.
  2. "Garbage collection" refers to software rather than drives. When a program no longer has use for variable space (usually strings or arrays) then that storage space becomes "garbage". Garbage collection refers to releasing that space to the memory manager for reuse. The user cannot do anything about garbage collection. The app developer has to do that, and the OS developer can provide tools to make it easier. "Trim" is a function used to help SSDs remain efficient. If you delete a file, the OS usually only wipes the filesystem directory entry and updates the bitmap to show those blocks are free space. The OS doesn't usually write zeroes to the blocks that the file used to occupy, because this would take time; the computer would act slower. However, the SSD is independent of any particular OS or filesystem. It doesn't know how to read directory entries or volume bitmaps. It keeps its' own map of blocks that have been written to, but internal SSD blocks are big. Say, 32 MB big. These are the smallest "zones" that an SSD can erase. Unlike a hard drive, an SSD cannot erase standard 512-byte blocks at will. Only relatively huge blocks. When it comes time to modify contents in an internal block, the SSD must do a dance. All unchanged data has to be copied to a standby block, along with the modified data. The old block is then erased and becomes a standby block. All of this takes time. If the SSD is running low on standby blocks (overprovisioning), it can take a lot of time for the SSD to consolidate used space into fewer blocks. Trim works by letting the OS notify the SSD that a particular space is actually free. Although data has been written to that space in the past, it should now be disregarded. When the SSD has to manage it's internal blocks, that space need not be copied. If the OS and SSD both support Trim, then it works automatically. Whenever a filesystem block is freed up, Trim passes the info to the SSD. The SSD uses the info to act more efficiently, which the user sees as the SSD running faster. As to your last question about Trim, the user could turn it off. But who would want to. A utility could be used to read an existing filesystem, then send Trim notices for every free block in the file system. This would be useful if the SSD had previously been used with an OS that didn't support Trim. Such OSes are in the past today, so such a utility wouldn't do anything.
  3. This is a timely and useful offer. Kudos to DriveSavers -- and it won't hurt them in the long run. People who need the service (or just hear of it) may well try DriveSavers first the next time. For anyone who does need it - remember, the drive(s) must be shipped by September 15.
  4. reader50

    News thread missing

    The recent DriveSavers story is missing its associated comment thread. I wanted to offer kudos to them for their timely offer. Also, I originally put this comment in the then-current comments thread here. My apologies - this feedback forum was the proper place. That misplaced comment should be deleted.
  5. reader50

    Crucial BX300 SSD Review Discussion

    Are the sizes a mistype? If accurate, the BX300 has regressed. BX100 (2015 review): 120, 250, 500 GB, 1 TB BX200 (2015 review): 240, 480, 960 GB BX300 (2017 review): 120, 240, 480 GB
  6. reader50

    Crucial M500 alternative

    WD recently announced 4-bits-per-cell 3D NAND. Not sure what we'll call it - QLC? 4LC? They didn't mention when product will ship, so 2018 at the earliest. Probably not helpful for your needs, but with 3D QLC coming, I expect 3D TLC is stable today.
  7. Why would the 4, 6, and 8TB be done via dual drives today? Single-drive solutions would be quieter, cooler, and far cheaper for those sizes.
  8. reader50

    10TB WD Black alternative?

    From retail drive pictures, the WD Gold appear to be rebranded HGST He drives.
  9. reader50

    10TB WD Black alternative?

    HGST does have a 12TB enterprise drive out, currently running $630 on ebay. I've yet to see it in the regular channels. Look for HGST He12 If you are looking for large economical storage, drives in the 6-8 TB range are approaching half the price-per-TB of that He12. A RAID array in a NAS would get you more storage, and probably at a lower price. Admittedly with more noise.
  10. reader50

    Newbie

    You posted your thread in the right place.
  11. reader50

    Newbie

    I find myself in agreement.
  12. reader50

    Any word of new 2.5 drives above 2 TB?

    It's been 15 months now, still no sign of a 3 TB drive in 9.5mm. Unless I want to drop $1500 on a 4TB SSD. I didn't think it would take this long for an upgrade to appear. Larger drives used to appear like clockwork.
  13. 16 levels of analog voltage per cell. It better have amazing error check and correction. I won't be the first one to try this. Side note, between higher bits-per-cell and 3D layouts, the bits-per-chip has gone up dramatically. I was expecting SSD prices to decline dramatically as density goes up. But they've stayed about the same (or even increased slightly) over the past year. What gives? The manufacturers can't all be in a conspiracy to prop up prices, can they?
  14. Any special reason why you're commenting on a 3-year-old article? You do realize some of these models most likely aren't made any more? SSDs are evolving quickly - models rarely stay on the market for years. Also, prices have come down. Who is going to consider a 200 GB drive for 870 EU when you can buy a (slower SATA-III) 2 TB SSD for $550 today?
  15. BackBlaze makes their raw data file available for download. You should be able to extract that data with a bit of scripting.
  16. According to the specs sheet downloadable from here, the IronWolf NAS 10TB is 7200 RPM. 4TB and smaller are 5900 RPM. Performance plateaus at 210 MB/s sustained for 7-10TB. It could be a limitation of the controller. I'd still be interested in a direct measurement. If the RPM were 5900 after all ... now there would be a story. Of course, SR might have trouble getting Seagate samples for awhile if you happened to break such a hypothetical story ...
  17. Interesting comparison. Toshiba 8TB, 7200 RPM WD Red 10TB, 5400 RPM Seagate IW 10TB, 7200 RPM I can see why the Toshiba would generally outperform the WD - higher RPM is overcoming the size difference. The more puzzling aspect is why the Toshiba edged out the IronWolf. Seagate's drive is the same RPM as well as larger. At least according to the specs. Did you run an acoustic check on the Seagate for primary frequency, or do a rotational latency check, to measure the actual RPM? If the Seagate were at 5900 RPM, the results would make a lot more sense. btw - this story gives the WD Red as 7200 RPM. But the actual Red review gives it as 5400.
  18. reader50

    12TB drives - availability?

    The HGST 12TB drives have appeared on eBay. US seller. Going around $700 each.
  19. reader50

    reliable 4tb internal drive 3.5

    There are only 4 brands making 3.5" drives today, so "top 3" is probably not useful. Here they are, more-or-less in order of reliability based on recent BackBlaze stats. HGST (owned by WD, consistently highest reliability) Toshiba (small BackBlaze pool, so stats show higher variability) Seagate (2nd largest, seems to have upped their quality the last couple years) Western Digital (largest one, seems to have become less attentive to quality lately)
  20. reader50

    Seems there is none new member here

    I read daily. Mostly reply on HD news, which isn't as frequent as we'd like. Bring on HAMR.
  21. The 03 or 04 part is the series number, it gives an indication of density and possibly power efficiency. Toshiba's 05 series has just hit the markets, with 04 still going strong. 03 is an older design today. I don't know what the G or D stands for.
  22. reader50

    RAID using WD Velocity Raptor HD's:

    If it's software RAID, you're all good. The hardware will see the drives as individuals. I've seen Raptors used in softraid before. Assuming it isn't software RAID, what controller are you using?
  23. OK, found a Toshiba 8TB for sale. Actual picture, and the listing claims 7 already sold. http://www.ebay.com/itm/371841480025 However, it's an MG05ACA800E enterprise drive. I don't recall anyone announcing this drive. The 8TB MN announced in this story is the MN05ACA800. Did Toshiba ship the MG 8TB without an announcement?