• 3 Posts
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Joined 1 year ago
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Cake day: August 12th, 2023

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  • Why isn’t this just the default?

    One may notice that for every new method, the old ways stay around, possibly forever. It is not the default because there were things that worked prior to flatpak. The distros that from before flatpak have likely added the capability, but won’t likely change their default for another decade, or more.












  • Looks like you have your answer, but there are a crazy number of possible issues.

    The biggest cause is misreading the performance specs.

    A partial list of other options:
    Mechanical drives store data in rings. Outer rings have higher speeds than inner due to constant angular velocity.
    Seeks cost a lot of throuput on mechanical drives.
    Oversubscribed drive cables.
    HBA issues.
    PCIe data path conflicts
    Slow RAM
    RAM full or busy
    Extra cpy within RAM
    NUMA path issues (of drives are connected to different NUMA nodes. Not an issue on desktops.)
    CPU too busy
    Transfer software doing extra things
    File system doing extra.
    RAID doing extra.
    NIC on a different NUMA node than HBA (can be good or bad).
    NIC sharing the data path in a conflicting way.

    There are others. Start with checking theoretical performance from data sheets.

    Also, details matter, and I don’t have enough of them to guess.