• 11 Posts
  • 73 Comments
Joined 1 year ago
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Cake day: June 4th, 2023

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  • Marxists believe Socialism is what Capitalism is necessarily leading to because decentralized markets form centralized monopolist syndicates with complex internal planning

    Jesus fucking Christ, I was just talking to a friend about how big corporations with hundreds of thousands of employees resemble centrally planned economies, and how consolidations creates them all around us and the only thing stopping them from becoming fewer is the attempts of some governments that haven’t been regulatory-captured yet to stop it. But regulatory-capture increases with wealth accumulation so if you keep running the system, it tends to total central planning. I haven’t read Marx and neither has he.

    On a separate but related point - what stops the system from being somewhat disrupted by labor in a way that redistributes huge amounts of the accumulated wealth, restoring the regulatory regime in favor of labor and restarting the cycle from that point, then repeat. In other words, what’s stopping it from doing a depression-FDR-redistribution every 100 years? I can absolutely see the inevitable end without labor intervention but to my current brain it seems possible to maintain it with. Is this wrong in some obvious way?










  • B350 isn’t a very fast chipset to begin with

    For sure.

    I’m willing to bet the CPU in such a motherboard isn’t exactly current-gen either.

    Reasonable bet, but it’s a Ryzen 9 5950X with 64GB of RAM. I’m pretty proud of how far I’ve managed to stretch this board. 😆 At this point I’m waiting for blown caps, but the case temp is pretty low so it may end up trucking along for surprisingly long time.

    Are you sure you’re even running at PCIe 3.0 speeds too?

    So given the CPU, it should be PCIe 3.0, but that doesn’t remove any of the queues/scheduling suspicions for the chipset.

    I’m now replicating data out of this pool and the read load looks perfectly balanced. Bandwidth’s fine too. I think I have no choice but to benchmark the disks individually outside of ZFS once I’m done with this operation in order to figure out whether any show problems. If not, they’ll go in the spares bin.



  • I put the low IOPS disk in a good USB 3 enclosure, hooked to an on-CPU USB controller. Now things are flipped:

                                            capacity     operations     bandwidth 
    pool                                  alloc   free   read  write   read  write
    ------------------------------------  -----  -----  -----  -----  -----  -----
    storage-volume-backup                 12.6T  3.74T      0    563      0   293M
      mirror-0                            12.6T  3.74T      0    563      0   293M
        wwn-0x5000c500e8736faf                -      -      0    406      0   146M
        wwn-0x5000c500e8737337                -      -      0    156      0   146M
    

    You might be right about the link problem.

    Looking at the B350 diagram, the whole chipset is hooked via PCIe 3.0 x4 link to the CPU. The other pool (the source) is hooked via USB controller on the chipset. The SATA controller is also on the chipset so it also shares the chipset-CPU link. I’m pretty sure I’m also using all the PCIe links the chipset provides for SSDs. So that’s 4GB/s total for the whole chipset. Now I’m probably not saturating the whole link, in this particular workload, but perhaps there’s might be another related bottleneck.


  • Turns out the on-CPU SATA controller isn’t available when the NVMe slot is used. 🫢 Swapped SATA ports, no diff. Put the low IOPS disk in a good USB 3 enclosure, hooked to an on-CPU USB controller. Now things are flipped:

                                            capacity     operations     bandwidth 
    pool                                  alloc   free   read  write   read  write
    ------------------------------------  -----  -----  -----  -----  -----  -----
    storage-volume-backup                 12.6T  3.74T      0    563      0   293M
      mirror-0                            12.6T  3.74T      0    563      0   293M
        wwn-0x5000c500e8736faf                -      -      0    406      0   146M
        wwn-0x5000c500e8737337                -      -      0    156      0   146M
    







    • Lenovo ThinkCentre / Dell OptiPlex USFF machine like the M710q.
    • Secondary NVMe or SATA SSD for a RAID1 mirror
      • Use LVMRAID for this. It uses mdraid underneath but it’s easier to manage
    • External USB disks for storage
      • WD Elements generally work well when well ventilated
      • OWC Mercury Elite Pro Quad has a very well implemented USB path and has been problem-free in my testing
    • Debian / Ubuntu LTS
    • ZFS for the disk storage
    • Backups may require a second copy or similar of this setup so keep that in mind when thinking about the storage space and cost

    Here’s a visual inspiration: