Igeometry Podcast

In this video I explain what is a zero day vulnerability or attack.   Fundamentals of Networking for Effective Backends udemy course (link redirects to udemy with coupon) https://network.husseinnasser.com --- Support this podcast: https://anchor.fm/hnasr/support

IPv4 UniCast Extensions Project attempts to unreserve old IPv4 subnets so they are publicly addressable. Is it worth it? Let us discuss  https://blog.apnic.net/2022/05/31/cutting-down-on-ip-address-waste/Unicast Use of the Formerly Reserved 127/8 https://datatracker.ietf.org/doc/draft-schoen-intarea-unicast-127/ Unicast Use of the Lowest Address in an IPv4 Subnet https://datatracker.ietf.org/doc/draft-schoen-intarea-unicast-lowest-address/   Unicast Use of the Formerly Reserved 240/4 https://datatracker.ietf.org/doc/draft-schoen-intarea-unicast-240/   Unicast Use of the Formerly Reserved 0/8 https://datatracker.ietf.org/doc/draft-schoen-intarea-unicast-0/ https://twitter.com/TheRealRevK/status/1532033651650830339   Fundamentals of Networking for Effective Backends udemy course (link redirects to udemy with coupon) https://network.husseinnasser.com --- Support this podcast: https://anchor.fm/hnasr/support

Fantastic gains in Postgres 15! improved sorting by 371%. Normally you can avoid sorting by using an index access path. However, you can’t always have an index on every group by, order by, join or distinct predict. This will come handy. Let us discuss Resources https://www.phoronix.com/scan.php?page=news_item&px=PostgreSQL-15-Faster-Sort https://techcommunity.microsoft.com/t5/azure-database-for-postgresql/speeding-up-sort-performance-in-postgres-15/ba-p/3396953#change3 https://www.postgresql.org/docs/15/release-15.html#id-1.11.6.5.4 https://techcommunity.microsoft.com/t5/sql-server-blog/understanding-sql-server-fast-forward-server-cursors/ba-p/383556 --- Support this podcast: https://anchor.fm/hnasr/support

In this episode of the backend engineering show I discuss UDP hole punching in details.  Fundamentals of Networking for Effective Backends udemy course (link redirects to udemy with coupon) https://network.husseinnasser.com --- Support this podcast: https://anchor.fm/hnasr/support

As a new parent, you get exposed to a whole new world. There is this new toddler song “Five little monkeys jumping on the bed” where it starts with five monkeys jumping on the bed and one falls off the bed and the mom calls the doctor and then another monkey falls and the mom calls the doctor again. This keeps going until all monkeys are no longer on the bed. This clearly looks like a software engineering problem. In the face of it is extreme inefficiency in IO with the mom calling the doctor 5 times in span of 3 minutes. The mom could decide to wait for all monkeys to fall and call the doctor once. A Method that is known as batching. Two problems with this approach; the first is latency the mom can’t wait, she is worried, she needs immediate answer from the doctor for the first monkey that fell. The second problem is we don’t know if more monkeys are going to fall off the bed, so while the mom waiting, the first monkey will be in pain and will “starve”. We makes decisions like this constantly in software eng

Eric Dumazet, a Linux kernel and a Google Principal software engineer pushed a new change to Linux to support a new feature in Linux called BIg TCP. How about we discuss this  resources https://www.phoronix.com/forums/forum/software/general-linux-open-source/1325637-linux-5-19-networking-brings-big-improvements-with-big-tcp-purelifi-more-hardware https://patchwork.kernel.org/project/netdevbpf/patch/20220524203159.1189780-1-kuba@kernel.org/https://datatracker.ietf.org/doc/html/rfc2675 --- Support this podcast: https://anchor.fm/hnasr/support

Database logging is a critical feature to maintain durability, in this show I discuss them in details   0:00 intro 1:00 ad 3:30 Start of the Show 6:00 What is commit 9:30 What if a commit fails half way 11:00 WAL 23:00 Checkpointing 27:00 fsync 33:00 Undo logs Get $20 off of your first order of cometeer quality delicious coffee https://cometeer.com/husseinnasser use coupon HUSSEIN20 ☕️ --- Support this podcast: https://anchor.fm/hnasr/support

In this video I discuss the developer mental health, stress, pressure, expectation, how to understand and shed light on the issues, and what might cause it all.  Fundamentals of Networking for Effective Backends udemy course (link redirects to udemy with coupon) https://network.husseinnasser.com --- Support this podcast: https://anchor.fm/hnasr/support

In this video I explain how we can use two-phase commit protocol works to achieve atomic distributed transaction.   0:00 What is atomicity  3:00 Distributed Transaction 6:00 Two phase commit protocol 13:00 Limitations of Two phase commit protocol    Fundamentals of Networking for Effective Backends udemy course (link redirects to udemy with coupon) https://network.husseinnasser.com Fundamentals of Database Engineering udemy course (link redirects to udemy with coupon) https://database.husseinnasser.com --- Support this podcast: https://anchor.fm/hnasr/support

Welcome to another database question. In this question I created a community poll question and provided some answers. All answers can be correct of course but the question is what is the most efficient? this is what I try to explore in this video and compare how different database platforms such as mysql or Postgres differ in those implementations; Table T with three integer fields A, B and C. A has a primary key clustered index. B has a secondary index. Which query is more likely to be the most efficient? 0:00 Intro 1:00 The Question 3:20 WHERE C BETWEEN 50,50000 5:30 WHERE B BETWEEN 50,50000 13:20 WHERE C BETWEEN 50,50000 Fundamentals of Networking for Effective Backends udemy course (link redirects to udemy with coupon) https://network.husseinnasser.com Fundamentals of Database Engineering udemy course (link redirects to udemy with coupon) https://database.husseinnasser.com --- Support this podcast: https://anchor.fm/hnasr/support

WhatsApp Went down again, this is an early report with brief analysis, enjoy.   https://engineering.fb.com/2020/10/21/networking-traffic/how-facebook-is-bringing-quic-to-billions/ --- Support this podcast: https://anchor.fm/hnasr/support

DNS or Domain Name System, despite its drawbacks, is brilliantly designed for scale. We can learn few lessons from this protocol especially when designing our own apps. This episode of the backend engineering show I go through how DNS works, the pros and the cons and attacks that happened on this system. 0:00 Intro 2:00 Overview DNS 7:40 How DNS works (Details) 15:44 DNS uses UDP 19:30 DNS Poisoning 24:10 is DNS really distributed? 26:30 How Attackers Abuse DNS 30:30 How Chrome overloaded the ROOT servers for 12 years Resources https://blog.apnic.net/2020/08/21/chromiums-impact-on-root-dns-traffic/ https://www.cloudflare.com/learning/dns/what-is-dns/ https://www.cloudflare.com/learning/dns/dns-cache-poisoning/ https://blog.cloudflare.com/sad-dns-explained/ https://medium.com/@alex.birsan/dependency-confusion-4a5d60fec610 Fundamentals of Networking for Effective Backends udemy course (link redirects to udemy with coupon) https://network.husseinnasser.com Fundamentals of Database Engineering udemy course (link

In this episode of the backend engineering show we discuss the Internet Protocol. A beautiful, elegant protocol that made the Internet possible. We discuss why we need an IP address, how routing is done and how VPNs take advantage of the agnostic nature to encrypt traffic --- Support this podcast: https://anchor.fm/hnasr/support

In this episode of the backend engineering show we discuss an article written by the Forem team illustarting a bug they recently fixed in their caching layers. They go into good level of details explaining the 3 levels of caching that they have. I go through this article in this episode and give my opinion at the end as to why we shouldn’t really cache unless we need to. Enjoy 0:00 Intro 1:00 Three level of caching summary 7:39 Edge Caching 8:30 Backend Rails Caching 10:30 Database Caching 15:00 Understand why you Cache Article https://dev.to/devteam/the-three-caches-of-forem-492p --- Support this podcast: https://anchor.fm/hnasr/support

Backend database applications relay on good storage systems for performance, durability and low latency. SSDs have been a great invention that changed the storage game compared to mechanical drives. However, SSDs came with their own sets of problems which can cause database reads and writes to plummet after a while. This episode discusses the current limitations of SSDs include garbage collection, wear leveling, over provisioning and how zoned name spaces “may” fix this. 0:00 Intro 1:40 Block 4:00 Logical Block Addressing 6:00 Flash Translation Layer 6:50 DRAM 8:50 Erase unit 11:11 Namespace 12:00 Summary 13:40 Garbage collection 16:49 Over provisioning 18:00 Write amplification 21:28 Wear leveling Resources https://www.guru3d.com/news-story/new-malware-bypasses-security-measures-by-using-ssd-over-provisioning.html https://www.snia.org/educational-library/zoned-namespaces-zns-ssds-disrupting-storage-industry-2020 https://www.youtube.com/watch?v=cbX3P56Jp0o&feature=emb_title --- Support this podcast: ht

Google linux boxes have over 16 NVMe SSD PCIe Express drives.When a shutdown signal is sent to linux, the OS iterate through each NVMe and send synchronous request to shutdown that takes 4.5 seconds. This adds up to over a minute to achieve a reboot. Google patches linux with asynchronous Shutdown APIs    Resources https://www.phoronix.com/forums/forum/phoronix/latest-phoronix-articles/1316262-google-has-a-problem-with-linux-server-reboots-too-slow-due-to-too-many-nvme-drives  patch https://lore.kernel.org/lkml/20220328230008.3587975-1-tansuresh@google.com/  Sync vs async  https://www.youtube.com/results?search_query=asynchronous+vs+synchronous+hussein --- Support this podcast: https://anchor.fm/hnasr/support

Hash tables are effective for caching, database joins, sets to check if something is in a list and even load balancing, partitioning and sharding and many other applications. Most programming languages support hash tables. However they don’t come without their cost and limitations lets discuss this. 0:00 Intro 1:50 Arrays 3:50 CPU Cost (NUMA/M1 Ultra) 6:50 Hash Tables 10:00 Hash Join 16:00 Cost of Hash Tables 20:00 Remapping Cost Hash Tables 22:30 Consistent hashing --- Support this podcast: https://anchor.fm/hnasr/support

Aggregate functions like Count, max, min, avg performance really depends on how did you tune your database for that kind of workload. Let us discuss this. 0:00 Intro 1:22 SELECT COUNT(*) 4:30 SELECT AVG(A) 5:15 SELECT MAX(A) 8:00 Best case scenario 11:30 Clustering 14:00 Clustering Sequential Writes 17:19 Clustering Random Writes 20:30 Summary --- Support this podcast: https://anchor.fm/hnasr/support

99% of phishing attacks can be avoided by looking at the URL. However this secuirty researcher proves that not enough.   https://mrd0x.com/browser-in-the-browser-phishing-attack/ --- Support this podcast: https://anchor.fm/hnasr/support

On March 8 2022 Spotify and Discord experienced an outage latest 2-3 hours. The reason was a configuration on the xDS formats on Google Traffic Director. Let us discuss how this change caused the outage and what Spotify did to mitigate that outage without relying on Google restoring the service back up. Resources Spotify outage https://engineering.atspotify.com/2022/03/incident-report-spotify-outage-on-march-8/ Google Cloud outage https://status.cloud.google.com/incidents/LuGcJVjNTeC5Sb9pSJ9o Envoy xDS https://blog.envoyproxy.io/the-universal-data-plane-api-d15cec7a Microservices scaling with common sense https://www.youtube.com/watch?v=NsIeAV5aFLE CARDS 4:36 Miicros https://www.youtube.com/watch?v=NsIeAV5aFLE 9:30 Spotify Hermes https://www.youtube.com/watch?v=fMq3IpPE3TU&t=21s 0:00 Intro 2:00 Spotify Outage 3:30 Microservices 6:10 Service Discovery 10:00 Spotify Quick Workaround 12:15 Google Traffic Director Outage --- Support this podcast: https://anchor.fm/hnasr/support