iiinova — where your digital self keeps evolving

Tanel Poder @tanelpoder.com · 18/06/2026

Releasing an eBPF Runtime Reporter and Profiler tool (brr). I've used it for profiling eBPF programs themselves. It unifies bpftop-like utilization/event frequency monitoring with perf_events based CPU sampling, with source code line mapping. github.com/tanelpoder/b...

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Tanel Poder @tanelpoder.com · 15/05/2026

Almost Summer Sale 2026: All my flagship video courses discounted until end of May! Plus *free* Exadata Internals & Advanced Performance Metrics seminar videos! tanelpoder.com/posts/almost...

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Tanel Poder @tanelpoder.com · 30/04/2026

A pretty recent summary article from Oracle on enabling and getting SQL monitoring reports in various ways (including historical captures): Real-Time SQL Monitoring: a MUST for SQL Tuning blogs.oracle.com/coretec/orac... (I'm working on something new & related too ;-)

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Tanel Poder @tanelpoder.com · 15/04/2026

I've been busy in the last months! Announcing a brand new "Practical Exadata Performance" training course! I'm not aware of any other training *like this* offered in the world. 😎 Also, a *free* seminar! Exadata is an awesome platform, if used right! learn.tanelpoder.com

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Tanel Poder @tanelpoder.com · 13/04/2026

Was doing some Exadata performance work and this question came up: "Where does the Exadata storage() predicate come from?" I wrote about it a while ago 😎 tanelpoder.com/2014/03/05/w... The inmemory() predicate works using similar logic: access_predicate on INMEMORY full table scan.

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Tanel Poder @tanelpoder.com · 10/04/2026

Get Oracle Partition High Values as VARCHAR2 types instead of LONG in Oracle 19c and earlier (new blog). There's also some data 23/26ai data dictionary internals! tanelpoder.com/posts/oracle...

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Tanel Poder @tanelpoder.com · 30/03/2026

Another old but interesting blog post (2008!) An Oracle database may have duplicate (non-unique) ROWIDs (and data object IDs) when using transportable tablespaces. That's not a bug, Oracle guarantees ROWID uniqueness only at table level, not at DB level. tanelpoder.com/2008/10/21/t...

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Tanel Poder @tanelpoder.com · 29/03/2026

Old but gold (2024): Oracle Hint Scopes and Join Level Cardinality Hint: tanelpoder.com/posts/oracle...

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Tanel Poder @tanelpoder.com · 24/03/2026

Old but gold! (2025) Find which Oracle SQL_ID hits the SQL*Net break/reset to client event: tanelpoder.com/posts/find-w...

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Tanel Poder @tanelpoder.com · 21/03/2026

The number of citations in my Google Scholar profile just reached a new order of magnitude! 100 citations! 😅 The most cited item is a patent from 2015 about *transparently* offloading parts of RDBMS SQL exec plans to distributed engines & hybrid cloud. scholar.google.com/citations?us...

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Tanel Poder @tanelpoder.com · 13/03/2026

Reasons why SELECT * is bad for SQL performance: An old blog (with Oracle-specific examples) with a whole range of reasons why. It's not only about network traffic and SQL plan execution, but client side processing and memory usage as well. tanelpoder.com/posts/reason...

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Tanel Poder @tanelpoder.com · 06/03/2026

I wrote an Oracle "ash_index_helper.sql" script 5 yrs ago, trying to pull all relevant info of top time-consuming *access paths* into one place, as a single SQL script. Summarize access paths to a schema or just one table/SQL. Too complex for a single script, time for AI? 😎

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Tanel Poder @tanelpoder.com · 01/03/2026

New blog: Testing the Datadog Explain Plan Visualizer with Oracle execution plans tanelpoder.com/posts/testin...

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Tanel Poder @tanelpoder.com · 16/02/2026

Discovered an awesome article (and the entire site) via HN. Example: "How is data stored?" www.makingsoftware.com/chapters/how...

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Tanel Poder @tanelpoder.com · 02/02/2026

Vinicius Grippa has created a cool implementation of SQL Flamegraphs for MySQL: MyFlames. GitHub repo here, look into demos/mysql-*.svg files for more examples: github.com/vgrippa/myfl...

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Tanel Poder @tanelpoder.com · 28/01/2026

If you clone the same (cat) photo into 360 versions, each rotated by one more degree, then put all these versions through a ViT embedding model, should the resulting cat-vectors look at least somewhat similar? I used a heatmap to answer this question! tanelpoder.com/catvector/

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Tanel Poder @tanelpoder.com · 28/01/2026

Back in the the day we did something similar (for Oracle execution plans), called PlanViz: tanelpoder.com/posts/sql-pl...

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Tanel Poder @tanelpoder.com · 28/01/2026

A free SQL explain plan visualizer tool by @datadoghq Currently for PostgreSQL, MySQL, MSSQL and MongoDB explain.datadoghq.com

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Tanel Poder @tanelpoder.com · 28/11/2025

(3 days left until the end of Black Friday Sale of my online training courses!) Also, an old post for Oracle nerds: "Oracle Shared Pool Internals: List Chunk Position in the LRU List" tanelpoder.com/posts/oracle...

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Tanel Poder @tanelpoder.com · 10/11/2025

Added a blog update about the V$PROCESS_MEMORY_DETAIL auto-population for processes with PGA growth to over 500MB. Enabled in Oracle 19.18+, so no "oradebug dump pga_get_detail" needed, just query the V$ views for a detailed "heapdump": tanelpoder.com/2014/03/26/o...

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Tanel Poder @tanelpoder.com · 10/11/2025

New scripts: vstat.sql & dstat.sql for showing Oracle Sysmetric history with 1-minute granularity (both from AWR and regular V$ views) tanelpoder.com/posts/oracle...

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Tanel Poder @tanelpoder.com · 03/11/2025

Also just fixed a "bug" in my yesterday's writing - it was late and I had picked a number from a wrong column for one explanation! :-) And that's exactly why I added the computed "optimizer cardinality misestimate" column to my XB scripts, so I wouldn't have to do such lookups & math manually.

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Tanel Poder @tanelpoder.com · 03/11/2025

New blog: xb.sql and xbi.sql - Explain Oracle Execution Plans Better! (Part 3 - Cardinality Misestimates) tanelpoder.com/posts/xb-sql...

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Tanel Poder @tanelpoder.com · 02/11/2025

I just extended the Black Friday sale to the whole month of November! All my existing full-week flagship courses are heavily discounted for the entire month, and more content coming soon! tanelpoder.com/posts/black-...

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Tanel Poder @tanelpoder.com · 29/10/2025

For example, this screenshot aggregates samples from an 1-hour range (by default, configurable with command line options) and you can toggle that yellow highlighted window with "w" and move with "[ ]" currently hardcoded width at 5min (but will be adjustable soon) 😎 tanelpoder.com/posts/xcaptu...

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Tanel Poder @tanelpoder.com · 24/10/2025

Previously on this show: Find which Oracle SQL_ID hits the SQL*Net break/reset to client event tanelpoder.com/posts/find-w...

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Tanel Poder @tanelpoder.com · 24/10/2025

Previously on this show: SQL Plan Execution FlameGraphs with Loop and Row Counts tanelpoder.com/posts/sql-pl...

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Tanel Poder @tanelpoder.com · 22/10/2025

Announcing my new Oracle Optimizer, Partitioning and I/O-Intensive Database Handling Deep Dive Training! If you run serious Oracle workloads on-premises or in the cloud and want to learn some practical *and* new things this year, this is it! tanelpoder.com/posts/new-or...

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Tanel Poder @tanelpoder.com · 22/10/2025

There's a new Data Guard in town (not the Oracle one). Cool to see Linkedin, OpenAI and Anthropic collaborating: arxiv.org/html/2502.01...

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Tanel Poder @tanelpoder.com · 22/10/2025

Filtering data in real time (at CERN) After early filtering, this snippet from the article: "At this stage, the remaining events are recorded to a 40 Petabyte disk buffer." A 40 PB *buffer* for data 🫠 lhcb-outreach.web.cern.ch/filtering-da...

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Tanel Poder @tanelpoder.com · 20/10/2025

tabhisthybrid.sql: Display Oracle hybrid histograms and filter cardinality estimates tanelpoder.com/posts/tabhis...

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Tanel Poder @tanelpoder.com · 12/10/2025

pqr.sql: Generate QR Codes with Pure SQL in PostgreSQL tanelpoder.com/posts/genera...

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Tanel Poder @tanelpoder.com · 16/09/2025

If you have eBPF "biolatency" style IO latency monitoring tools always-on, you might want to reduce its tracepoint CPU overhead by not storing IO start times in a shared hashtable at all. In my results, 59x lower tracepoint CPU overhead at 37M IOPS 😎 tanelpoder.com/posts/optimi...

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Tanel Poder @tanelpoder.com · 11/09/2025

Already getting good questions about 0x.tools in YouTube!

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Tanel Poder @tanelpoder.com · 09/09/2025

The xCapture and xtop eBPF tools are now in beta, with a demo dataset! With a pre-recorded xcapture dataset from my dev server, now you can play with xtop "thread activity sampling" drilldown even on your laptop, without having to run xcapture yourself! (link in replies :-)

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Tanel Poder @tanelpoder.com · 27/08/2025

Something for Linux block I/O nerds - Linux Storage Stack Diagram (up to kernel v6.16) published: www.thomas-krenn.com/en/wiki/Linu...

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Tanel Poder @tanelpoder.com · 25/08/2025

I have published the CatVector embedding-vector heatmap visualization app (for learning and fun!) as a static webpage now (just browser is enough, no downloads or Python needed). And now we have dark mode too! 😼 tanelpoder.com/catvector/

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Tanel Poder @tanelpoder.com · 22/08/2025

YouTube helpfully generated a table of contents for my 11 minute demo video of 0x.tools xtop "top for wall clock time" dimensional performance analysis tool. You see I'm talking about multiple topics there (including syscall,TCP,IO latency) www.youtube.com/watch?v=cZ_z...

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Tanel Poder @tanelpoder.com · 21/08/2025

This is what I'm currently playing with: *Passive sampling* of hardware interrupt stacks with eBPF. With xintr, you'll soon be able to see inside your interrupt activity even on cloud VMs without hardware performance counters and without kernel probe & tracepoint overhead! Demo link in replies.

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Tanel Poder @tanelpoder.com · 19/08/2025

What if I told you that now it's possible to see inside hardware interrupt handling activity, even without PMU access on cloud VMs, without tracing or slowing anything down? Thanks to passive sampling with eBPF, task iterators and some pointer chasing, this is now a thing 😎

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Tanel Poder @tanelpoder.com · 17/08/2025

As I'm creating new content for my latest online training courses, I just bundled the 2021 "Troubleshooting Very Complex Oracle Performance Problems" videos into the AOT & SQL Tuning courses, without an extra fee; existing attendees will have access too! learn.tanelpoder.com

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Tanel Poder @tanelpoder.com · 15/08/2025

Achieving 11M IOPS & 66 GiB/s IO on a Single ThreadRipper Workstation. This post was about I/O & hardware geekery, but if you want to learn some thing about modern "computers are networks" topology and PCIe root complexes and some bottlenecks I hit, check out this: tanelpoder.com/posts/11m-io...

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Tanel Poder @tanelpoder.com · 14/08/2025

New Tool: xstack - Completely Passive eBPF Linux Stack Profiling Without Any Tracepoints tanelpoder.com/posts/xstack...

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Tanel Poder @tanelpoder.com · 13/08/2025

A new tool in 0x.tools family: xtop - Top for Wall-Clock Time. It uses eBPF/xcapture v3 and gives you "x-ray vision" into Linux system activity. It will be available on next Tuesday 19 Aug at 1pm EDT when I also run a live demo webinar! tanelpoder.com/posts/xtop-t...

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Tanel Poder @tanelpoder.com · 12/08/2025

MySQL's New Storage and Execution Engine: DuckDB www.linkedin.com/pulse/mysqls...

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Tanel Poder @tanelpoder.com · 02/07/2025

New Webinar: Testing High-Performance Vector Search With CatBench on Google AlloyDB Omni Time: Wednesday, July 23th at 9am EDT. Sign up here: rsvp.withgoogle.com/events/bench... More info: tanelpoder.com/posts/testin... /cc @kirantailor.bsky.social

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Tanel Poder @tanelpoder.com · 30/05/2025

Here's the link (and some cats!): tanelpoder.com/posts/catben...

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Tanel Poder @tanelpoder.com · 30/05/2025

New Blog: Catbench Vector Search Playground has Postgres Query Throughput and Latency Monitoring Now This is a demo app that helps you to learn and experiment with adding vector search-based functionality into new or existing apps! (link in reply)

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Tanel Poder @tanelpoder.com · 28/05/2025

New blog: Using Postgres pg_test_fsync tool for testing low latency writes An easy to use tool that comes with standard Postgres installation, for testing write latency of devices where you put your WAL/redo logs and any other files requiring low write latency. (link in reply)

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