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Docker / runC, Zero page list, IO, Schedules, LoRa, CDN, TLS 1.3, Ceph, Libreboot

posted Dec 4, 2016, 6:34 AM by Sami Lehtinen   [ updated Dec 4, 2016, 6:34 AM ]
  • Very nice Docker / runC post by Julia Evans: "I just want to run a container!" - I've been dealing a little with docker, very basics on only. And I loved the post covering many important questions which many people miss, like the benefits on shared libraries etc. That's why light 'containerization' is much better option in many cases than the full virtualization. Of course full virtualization also adds OS licensing costs and other horrible fees, ofter costing much more than the hardware costs alone.
  • Today I learned once again something new. I could be enthusiastic about this like Julia often is. ;) - W0w, Windows uses Zero Page List. That's awesome. Wait, but what is zero page list? What's the difference between free page and zero page? - I was amazed when I found that out. - The difference between free and zero page is that pages in zero page list are written to zero. Free page still contains some gunk left by previous process. Zero page is guaranteed to be clear and clean aka zeroed out. Pages from zero page list can be instantly assigned for processes requiring a memory page without wiping it clean before handling it forward. - That's amazing. I didn't know that there's separate list for those. From most of documentation it's clear that Windows manages memory so that pages do look being zeroed out to processes when allocated. But technically it wouldn't mean that it would be zero in RAM. - I practically thought that the page zeroing would happen on first actual write to that page and there would be just 'show as zero' flag or something, before that first write, so all reads to that page would return zero. But I assume there's some low level reasons why managing that might not be feasible. It's just like that ZRAT with SSD. If page has been trimmed, it always returns zero, even if the actual data on disk haven't been probably wiped yet via the NAND block erase process.
  • Battled more cloud disk I/O latency issues. Ouch. I hope it gets resolved.
  • In one random case, one Gantt Chart step has been expanded from one week to 14 weeks and they still think the deadline for whole project is the same. Not going to fly. Always as funny. I ask if they can deliver something before Xmas (in start of October). Then I sit on the decision for 8 weeks and start frantically complaining about their delivery promises being bad. I'm ordering now and you promised to deliver before Xmas. - Hmm, maybe I should put a Grumpy Cat image here or something?
  • Digita is going to provide LoRa in Finland. That's great news. Then we're going to have several IoT networks. Sigfox was announced earlier. All kind of IoT sensor networks are coming fast now.
  • Yahoo leaking mails to FBI & NSA? No surprises there. I guess most of other lager cloud services are doing exactly the same, they haven't been just caught doing it yet. - Crime is ok as long as you don't get caught?
  • It's very hard to tell where a website will be served without experimenting. Because ISP and routing things are so complex. As example can be served at least from Frankfurt, Stockholm or Moscow depending which ISP you're using in Finland. Similarly sites hosted by CloudFlare can come at least from Helsinki, Stockholm or Moscow.
  • Industry Concerns about TLS 1.3 - Interesting post. This just shows you how secure the HTTPS is, main concerns in this post was that it's going to be harder and more expensive to eavesdrop TLS sessions. Is that bad? It seems to be, they say. Of course end point snooping agents are very useful, in multiple cases. So doing it with one network snooping device isn't as effective.
  • Extremely annoying performance problems with Ceph. No joy. And those problems are continuing, week after week. Sigh. Not fun at all. Only good thing is that there hasn't been data loss so far.
  • Quickly checked the Libreboot project. Nice. Finally a way to get alternate BIOS / UEFI code. Yet it remains to be seen what the actual compatibility is. One of my friends complained that nothing never works with Linux. Well, it does, if it's supported, if it isn't then it's quite obvious. If I would have time or interest it might be really nice to play a little with Libreboot. But nope, really can't do that.
  • I've got a couple of old Android phones, rooting those would be fun experiment too. But I don't have time for that either.