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Oracle Adds Data-integrity Code To Linux Kernel

Posted by timothy on from the put-your-trust-in-larry dept.

jazir1979 writes "ZDNet is reporting that Oracle has added code to the Linux kernel for ensuring data integrity. The code has been developed in partnership with Emulex and was recently accepted into the 2.6.27 kernel release." According to the article, "The code adds metadata to data at rest or in transit, to monitor whether that data has been corrupted. It helps make sure that I/O operations are valid by looking at that metadata — which acts as verification information — exchanged during data transmissions."

7 of 53 comments (clear)

  1. Terribly old news by zdzichu · · Score: 3, Informative

    Block integrity patches were discussed in excellent article on LWN in July 2008. Kernel 2.6.27 was released in October 2008. This is old news.

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    :wq
    1. Re:Terribly old news by Nick+Ives · · Score: 4, Informative

      That LWN writeup is far better too though, TFA is terrible. LWN makes it clear that this adds device checksum support, i.e. if your SATA drive supports adding checksum data to blocks this patch will enable that functionality.

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      Nick
  2. Re:Congratulations... Oracle by setagllib · · Score: 2, Informative

    I don't know where it fits either, but ZFS and eventually BTRFS actually have checksums at the block level, and can heal over corrupted blocks using redundant copies whose checksums do work. That alone is enough reason to use ZFS for a file server, but similar improvements could be made inside the Linux stack without a new filesystem on top. However ZFS' reliability also comes from copy-on-write updates which is not trivially installed into an existing filesystem.

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    Sam ty sig.
  3. Re:Congratulations... Oracle by scheme · · Score: 3, Informative

    I'm not certain but it appears to be checksumming data while it is moving around the kernel after a write or read call is made.

    Seems like something that should be handled in hardware with ECC, but what do I know.

    Kernel bugs can cause data to get corrupted and hardware ECC won't correct that. Likewise with transfers from memory to disk. Ultimately it'll need to be a hardware/software thing but the software portion is needed as well.

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    "When you sit with a nice girl for two hours, it seems like two minutes. When you sit on a hot stove for two minutes, it
  4. Re:vs a journaled fs? by JohnFluxx · · Score: 2, Informative

    The purpose of a journal is to make sure that operations either happen or they don't happen - i.e. you don't leave the filesystem in some half way state if the power goes out.

    It doesn't verify the actual data written or anything.

  5. Re:Dumb question... by afidel · · Score: 3, Informative

    It doesn't matter much. This patch adds T10-DIF which basically brings minicomputer level data integrity to the commodity computer market. It adds about 1.54% to data storage requirements (8 bytes of ECC per 512 byte block, just like the AS/400) and some small amount of code at the OS and APP layers to check the CRC's. With Oracle I would imagine this might actually INCREASE performance for the most fault intolerant environments since it wouldn't need to do a read after write if the storage system acknowledged a successful T-10 DIF block save.

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    There are 4 boxes to use in the defense of liberty: soap, ballot, jury, ammo. Use in that order. Starting now.
  6. Re:Congratulations... Oracle by Detritus · · Score: 2, Informative

    One of the problems that this is supposed to detect is blocks getting written to the wrong place or being read from the wrong place. I think it's one of those rare problems that stops being quite so rare when you have huge amounts of data stored on cheap hardware.

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