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Isolation, Problem Solving, SEPA, Bloat, Thunderbird+Outlook, DDoS Mitigation, Gartner's Cloud, Roche Limit

posted Jul 14, 2018, 11:40 PM by Sami Lehtinen   [ updated Jul 14, 2018, 11:40 PM ]
  • Many databases don't provide snapshot isolation. That's kind of problematic for some long running transactions. Of course you can read only the most vital data with read committed and rest of data with nolock. But problem with nolock is that it also reads uncommitted data. I don't actually care about getting fully consistent snapshot. But I generally don't want to read uncommitted data, which nolock option triggers. Using read committed snapshot would be ideal, because I usually don't write to database at all. I would just prefer getting a static snapshot with committed data to work with. - Snapshot Isolation in SQL Server.  Btw. SQLite (SQLite3) when used in WAL mode provides by default READ COMMITTED SNAPSHOT isolation level.
  • I really appreciate people who provide blatant disinformation. One claims that there's a problem with credentials. Which is a blatant lie. If DNS doesn't resolve. Or you're not getting a SYN-ACK back when trying to connect. There's absolutely nothing wrong with your credentials. Because credentials are absolutely irrelevant in most cases at that stage. So, please, don't claim there's a problem with your credentials, when there obviously isn't. And even if there would be, you wouldn't even know it. - This is why it's good idea to generically describe issues on higher level, without drawing too many conclusions.
  • SEPA Instant Payments / Instant Credit Transfer -  - This is going to be something big. We're already using similar national services, but this will enable EU wide instant transactions. Which will be naturally awesome. KW: fintech
  • Sometimes things are done in pretty inefficient way. Today I downloaded 24 GB zip packet, which contained one ISO file. Which contained Clonezilla live with disk image, which contained life Windows with NTFS partition and then the running system contained the actual files which I needed. Size of those files were 48 megabytes. Sigh, it's nice to wrap stuff wrapped in several other obfuscation layers. - Thank you so much for delivering such bloat. I would like to think that they were just trolling me. But sometimes things are made 'easy' by making those absolutely horribly overly complex. Maybe they thought that sending whole live disk image, would somehow make the things simpler. Or I could have just as well used Clonezilla without live anything.
  • Thunderbird + Microsoft Outlook. This seems to be invincible combination of problems, because Thunderbird works randomly and Microsoft Outlook works randomly. When you combine two pieces you'll get infinitely many problems. Everything fails, and is slow and then fails again. Now they claim I've got 12 gigabytes of mail and 200k emails in trash folder to be downloaded. Nope, I don't have that kind of loads of email. But Microsoft seems to think so. System is running infinite Amok run. Even closing and restarting systems won't help, it might be actually making the situation worse. I also cleared trash, but did it change anything? Nope. Reset local trash, did it change anything? Nope. And as bonus of all this, Microsoft cloud services are so inhumanly slow, that downloading those duplicate messages would take nearly forever. Btw. I never had these problems when I run my own server with Postfix and Dovecot. I guess the process where I deleted bunch of messages is in some kind of loop, which doesn't finish and starts all over again. Quite classic state management problem. But how do you clear that task queue? I've got no idea.
  • How to choose authenticated encryption. Reminded my-self about basics again. kw: CBC, CTR, GCM, AE, AEAD, OCB, EAX, CCM
  • It seems that DDoS and generic system attacks are getting worse and worse again. It's funny how attacks get worse when attackers assume that key personnel are on vacations. They know it might take longer to respond. The distributed (but centrally managed) attack prevention system got over 50000 attacking IPv4 addresses blocked right now. That's much more than I expected to see before implementing it.
  • Read Gartner's Cloud Infrastructure as Service report. IaaS, PaaS, aPaaS, Cloud Service Brokerage (CSB), Cloud-Enabled System Infrastructure" (CESI), High-Performance Computing (HPC), IT operations management (ITOM, managed service provider (MSP), system integrator (SI), Amazon Web Services (AWS), Google Cloud Platform (GCP), Microsoft Azure, Provider maturity model.
  • Something different? Roche limit. Asronomy, orbiting mass, planets, planetary rings.