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SSD, SQLite3 Vacuum, Inefficient, Neural Networks, Storage Tiers, VDSL2, Sound Canceling, EmDrive

posted Feb 19, 2017, 12:14 AM by Sami Lehtinen   [ updated Feb 19, 2017, 12:15 AM ]
  • Laughed at the post telling that Spotify writes a lot of crap to SSD. - Only because they seem to run SQLite3 Vacuum way too often. That's absolutely stupid. It's nice to see that even large companies write utter crap'o'ware software. Vacuuming database monthly should be more than enough for Spotify. There's no reason what so ever to do it several times / minute or so. - Horrible, bad, insane, silly, stupid and I really don't care code is the norm. This should be totally obvious for everyone, except the most ignorant coders. It works, it's great code! Or maybe they've written it as intentional sabotage? Let's put something really crazy here and see if anyone notices. It's nice to do that kind of checks every now and then. To see if the peer reviews and stuff work at all. In this case it's also funny that fixing such a fail would take them half a year. Any competent guy should be able to fix that in minutes. - Most of my projects vacuum sqlite3 databases monthly. If database is basically insert only, then I often use yearly vacuum. This is to to reduce index fragmentation. Data doesn't get fragmented, because there are no deletes / updates which would create fragmented records / leave empty space in database.
  • I've seen projects which consume Gigabytes of memory and almost all available CPU time. While doing, nothing. Yes, absolutely nothing. Program is just written very inefficiently, loops over same data over and over again without any optimizations and doesn't have any sane sleep, or trigger mechanisms in it. - But hey, it's not bad code. It works. It's just horribly inefficient. If someone complains system running out of resources or slowly, you can always add memory and CPU cores to keep running these utterly unnecessary brain dead tasks.
  • Had long, long discussions about evolutionary algorithms and machine learning. How much it's just statistics and 'brute force' finding the right values. In many simpler cases, that's just one way to do it. Here's the Neural Network Zoo, which visualizes some of the network arrangements. Very nice article, even if it's long, I couldn't stop before having it completely read.
  • Played a little with Windows 10 and Tiered Storage, just to lean more about services provided natively. It's real joy to get this configuration done using PowerShell. Even if Windows is all about GUI, these features can't be configured without using PowerShell. For more information see Storage Tiers Performance in TechNet.
  • Stupid or Smart solution? Who can judge. Party A says they can only deliver VDSL2, that's great. Then we can connect VDSL2-Ethernet media converter with 20cm cat3 cable to the VDSL2 DSLAM and use Ethernet connection from that point to the end site. All these last mile discussions are always so ridiculous. But this is just 'software engineers' solution. Code A is crappy and buggy, let's write code B which works as proxy and fixes fails with A. Been there done that, countless times. Thanks, WebService / JSON / REST world. It seems that the network layer is similar. There's optical fiber to the end, but one party only agrees to deliver Internet over VDSL2. So you can use just few centimeters of VDSL2 and then switch back to single mode optic fiber or CAT6 Ethernet. Makes perfect sense, right? - If you think these solutions are stupid, have you ever used lately VGA cable? If so, welcome to the club. It's totally stupid to connect digital output to digital display with analog connection. But it works, so maybe it's smart? Who knows.
  • Sound Canceling Devices - Sample videos om YouTube are amazing, but I'm pretty sure these are fakes / prototype (fantasy) promotion. If those devices would actually work, I'm sure there would be someone would be selling these with free shipping and returns. Because I would definitely buy several instantly. And I've got plenty of friends whom would do the same. - Try before buy, should be clear. If they trust their product, no BS, it shouldn't be any kind of problem.
  • EmDrive - confirmed to work. That's major news. I'm still extremely curious how it's actually working. Waiting for first in orbit tests.