Tanel Poder 🇺🇦 @TanelPoder Twitter profile

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Tanel Poder 🇺🇦

2 days

I have uploaded the video from my today's 0xtools eBPF talk here: Github code, slides, discussion:

xcapture-bpf v2.0.0 beta code and slides uploaded · tanelpoder 0xtools · Discussion #38

Slides: https://speakerdeck.com/tanelpoder/0x-dot-tools-with-ebpf-beta-release-and-demo Code: xcapture-bpf xcapture-bpf.c Video: Uploading in the next few minutes (will update here) Q&A I'l...

github.com

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Tanel Poder 🇺🇦

@TanelPoder

11 days

Harlequin: The SQL IDE for Your Terminal (works also with DuckDB!)

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Tanel Poder 🇺🇦

@TanelPoder

5 years

I usually try to stick with very basic Linux performance tools (vmstat,iostat,sar) to avoid depending on a customer's server having fancier tools installed. But one awesome tool that makes me break this philosophy is "dstat". It does formatting so much better - recommended!

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Tanel Poder 🇺🇦

@TanelPoder

2 years

@lukaseder @TheFigen_ Also, this seems pretty unlikely:

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Tanel Poder 🇺🇦

@TanelPoder

6 years

New blog: Visualizing SQL Plan Execution Time with FlameGraphs

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Tanel Poder 🇺🇦

@TanelPoder

6 years

My Performance & Troubleshooting scripts (TPT) for Oracle are now in GitHub and open sourced

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Tanel Poder 🇺🇦

@TanelPoder

6 years

New blog: Troubleshooting log file switch (checkpoint incomplete) wait events and LGWR waiting for checkpoint progress.

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Tanel Poder 🇺🇦

@TanelPoder

7 years

A nice Oracle 12c DB Architecture poster (PDF):

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Tanel Poder 🇺🇦

@TanelPoder

13 days

TIL there's a tool httpstat: /thx @JLarky

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Tanel Poder 🇺🇦

@TanelPoder

5 months

SRE Deep Dive into Linux Page Cache

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Tanel Poder 🇺🇦

@TanelPoder

6 years

Announcement: I will be doing my Advanced Oracle SQL Tuning online training & Advanced Oracle Troubleshooting class and even a *new* Linux Performance & Troubleshooting training within the next 6 months! See more details & sign up here :-)

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Tanel Poder 🇺🇦

@TanelPoder

5 years

Found an easy way (for me) to remember all the needed command line arguments for "netstat" :)

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Tanel Poder 🇺🇦

@TanelPoder

5 years

Wanna see which process is the bottleneck in your Linux command line chain - #pSnapper can help: Tar spending most of its time *waiting* writing output to STDOUT. Gzip is 100% on CPU and consumes as fast as it can. Gzip's CPU usage hits the bottleneck!

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Tanel Poder 🇺🇦

@TanelPoder

4 years

After 10 years in making, help.sql now documents an index of TPT scripts for Oracle troubleshooting (currently 118 out of ~1000 scripts are documented there). Enjoy #troubleshooting #oracle #performance with #tpt ! :-)

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Tanel Poder 🇺🇦

@TanelPoder

5 years

WTF of the day: Amazon buying Oracle - wouldn’t that be interesting? :-)

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Tanel Poder 🇺🇦

@TanelPoder

4 years

I have uploaded the 3 hour Oracle state objects & system state dumps hacking session to YouTube. Enjoy!

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Tanel Poder 🇺🇦

@TanelPoder

4 years

In the next hacking session I'll probably do a hard-core deep dive into spinlocks/mutexes and related low-level CPU scheduling issues. Interested?

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Tanel Poder 🇺🇦

@TanelPoder

6 months

Getting ready to publish the "2024 edition" of my Linux performance & troubleshooting training course (that I've been working on for quite a while!). My new toy arrived quite on time!

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Tanel Poder 🇺🇦

@TanelPoder

6 years

Secret Hacking Session: Oracle Background Process Communication, Exotic Wait Events and Some Tracing too

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Tanel Poder 🇺🇦

@TanelPoder

4 years

Can some Unix people help me, I've been told you can use cat to display a file's contents on the screen?

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Tanel Poder 🇺🇦

@TanelPoder

2 months

Systematic SQL optimization explained in one sentence: Measure what takes the most time in your SQL execution and *do it less*!

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Tanel Poder 🇺🇦

@TanelPoder

6 years

I have uploaded today's SQL Monitoring hacking session video to youtube and also recorded a new short Oracle Write Consistency hacking session video too! . See you at the ASH hacking session next Wednesday!

Oracle SQL Monitoring and Write Consistency Demo

This hacking session demonstrates the effect of Oracle's write consistency requirements and statement restarts done under the hood when specific conditions a...

www.youtube.com

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Tanel Poder 🇺🇦

@TanelPoder

1 month

@gunnarmorling One is from Microsoft, the other from Oracle?

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Tanel Poder 🇺🇦

@TanelPoder

5 months

Accidentally discovered a website with open-source related articles and multiple useful-looking FREE ebooks to download:

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Tanel Poder 🇺🇦

@TanelPoder

6 years

I'm running two free "hacking session" webinars in September! Wed 5 Sep - Oracle SQL Monitoring hacking & less known stuff + Wed 12 Sep - Getting the Most Out of Oracle ASH with my ashtop.sql scripts etc. Will be fun, see you there!

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Tanel Poder 🇺🇦

@TanelPoder

5 years

New Oracle Internals Blog: What Caused This Wait Event: Using Oracle's wait_event[] tracing

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Tanel Poder 🇺🇦

@TanelPoder

5 months

Wow Oracle 23c, has distributed Raft based replication "Raft replication provides built-in replication for Oracle Globally Distributed Database without requiring configuration of Oracle GoldenGate or Oracle Data Guard."

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Tanel Poder 🇺🇦

@TanelPoder

4 years

10 Things I Hate About PostgreSQL

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Tanel Poder 🇺🇦

@TanelPoder

4 years

If I were to give out Oracle DB-related awards, I’d give them to: 1) The group that invented ASH ( @OracleGraham @JBeresniewicz @kylelf_ ) 2) @oraclebase for all his work helping me to not have to think too much when setting up stuff or quickly learning new features. #WFHawards

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Tanel Poder 🇺🇦

@TanelPoder

5 years

New scripts xb.sql and xbi.sql: eXplain Better for Oracle - part 1:

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Tanel Poder 🇺🇦

@TanelPoder

4 years

Announcing my retirement (in 2030)!

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Tanel Poder 🇺🇦

@TanelPoder

4 years

Oracle Performance Troubleshooting Without OS Access, Part 1: Identifying CPU Scheduling Latency

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Tanel Poder 🇺🇦

@TanelPoder

4 years

I have uploaded my Troubleshooting Complex Oracle Performance Problems presentation slides to slideshare: And the videos are in YouTube (split into 2 parts):

Tanel Poder

This is Tanel Poder's computer performance & troubleshooting channel. Data, Databases, Linux, Scale-out, Scale-in & Cloud stuff. https://tanelpoder.com

www.youtube.com

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Tanel Poder 🇺🇦

@TanelPoder

5 years

New blog tutorial: Troubleshooting Linux SSH Login Delay - Why does logging in always take 10 seconds?

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Tanel Poder 🇺🇦

@TanelPoder

1 year

Oracle Database 19c is available for ARM platforms (aarch64)! Should be able to natively run it in a VM on the Apple Silicon Macs too.

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Tanel Poder 🇺🇦

@TanelPoder

2 months

Oracle 23 is called "23ai" now?

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Tanel Poder 🇺🇦

@TanelPoder

5 years

Too lazy to open a spreadsheet for totaling up numbers on your terminal screen? This helps: $ alias total='cat | awk "{ x=x+\$1 } END { print x }"'

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Tanel Poder 🇺🇦

@TanelPoder

5 years

How many DBAs does it take to buy a train ticket? #tvdpdays @ChrisAntognini @JLOracle

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Tanel Poder 🇺🇦

@TanelPoder

1 year

Systematic SQL optimization in one sentence: Measure what takes the most of your SQL execution time and *do it less*.

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Tanel Poder 🇺🇦

@TanelPoder

6 years

I'm running an advanced troubleshooting webinar next week: Troubleshooting a Complex Oracle Performance Issue. It's a case study of a complex problem troubleshooting + useful ASH scripts. Time: Tuesday Jun 12, 2018 12:00 PM EDT Register: See you soon!

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Tanel Poder 🇺🇦

@TanelPoder

2 months

FYI you can *download* the Oracle Autonomous Database FREE (container image)! DB version 19.22 (ADB image version 24.3). Max storage 20 GB, but you can test autonomous stuff (like automatic index creation and SQL Dev web) out with your dataset locally!

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Tanel Poder 🇺🇦

@TanelPoder

4 years

As promised, I'll deliver another Troubleshooting Complex Oracle Performance problems hacking session today! This one will be more practical than the previous internals deep dive, but still fun! ;-) Date & Time: Thu 30 Jan 12pm-1:30pm ET Register here:

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Tanel Poder 🇺🇦

@TanelPoder

6 years

New blog (Oracle): Scripts for Drilling Down Into Unknown Optimizer Changes

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Tanel Poder 🇺🇦

@TanelPoder

4 years

If you want me to run a quick hacking session about Oracle instance state objects' internals on this Wednesday 8. Jan 2020 @ 12pm ET, then retweet this tweet. If I get more than 42 RTs, I'll do it! ;-) #oracle #hackingsession

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Tanel Poder 🇺🇦

@TanelPoder

4 years

Announcing the next Virtual Conference: Oracle SQL Optimization in 2020! Dates: April 23-24 2020 Speakers: @JLOracle @CaryMillsap @Mautro @KerryOracleGuy @TanelPoder See you there!

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Tanel Poder 🇺🇦

@TanelPoder

6 years

Generate Oracle SQL Monitoring Reports as *HTML*, using SQL Developer v18.3. No Flash needed!

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Tanel Poder 🇺🇦

@TanelPoder

6 years

I have uploaded the Oracle ASH hacking session videos to my youtube channel:

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Tanel Poder 🇺🇦

@TanelPoder

4 years

I have some awesome announcements coming up! 🤓😎

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Tanel Poder 🇺🇦

@TanelPoder

5 years

I've been using Linux for 25 years (since '93) and I *finally* figured out how to remember all the options required for pstree: $ alias ptree='pstree -laugh' or... $ alias ptree='pstree -gulp' ...will also do. This site helps! ->

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Tanel Poder 🇺🇦

@TanelPoder

4 years

script: Measure CPU scheduling latency of a process at Linux level (without needing root access):

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Tanel Poder 🇺🇦

@TanelPoder

6 years

Did you know that you can run ALTER SYSTEM CANCEL SQL in Oracle 12.2 too, it's not just documented in that version :)

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Tanel Poder 🇺🇦

@TanelPoder

5 years

This still feels a little surreal

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Tanel Poder 🇺🇦

@TanelPoder

5 months

Wrote a new blog entry over a while - and it's a followup to my blog entry from 2007! :-) Oracle Index Parallel Degree Fix After Parallel Creation or Rebuild

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Tanel Poder 🇺🇦

@TanelPoder

4 years

Mark your calendars for an end-of-the-month Oracle hacking session, as promised: Thursday 30 Jan 2020 @ 12pm-1:30pm ET (9am PT) This one will be more practical than the previous geek-dive, will be more about troubleshooting examples + some slides too. Details & link tomorrow!

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Tanel Poder 🇺🇦

@TanelPoder

5 years

Sneak peek into what's coming in pSnapper 0.14 - real time file name lookup for I/O syscalls!

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Tanel Poder 🇺🇦

@TanelPoder

2 years

How is it possible to have v$sql Executions = 1, but Starts = 10 in an Oracle execution plan? The answer is (JDBC) statement batch execution. A bunch of stmt.addBatch() calls, followed by one stmt.executeBatch() will result in 1 Execution, but with multiple Starts..

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Tanel Poder 🇺🇦

@TanelPoder

5 years

Announcing the Linux Process Snapper tool and a Linux Troubleshooting Hacking Session (3rd April 9am PDT):

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Tanel Poder 🇺🇦

@TanelPoder

1 year

Just started reading Cary Millsap & Jeff Holt's new book Tracing Oracle - should be fun! I like the ideas there, like the "oceans-islands-rivers" approach for detecting which SQLs (that come from some connection pool) are part of the same app transaction.

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Tanel Poder 🇺🇦

@TanelPoder

2 months

As part of the Oracle 23c rebranding to Oracle 23ai, the entire RDBMS codebase is now written in the "ai" language and the storage cellsrv software is in "ai++". Oracle Client Interface is called OaiI now and there's also Pro*ai. (you're welcome)

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Tanel Poder 🇺🇦

@TanelPoder

5 years

I have uploaded the Linux /proc and pSnapper hacking session videos to youtube (and created a landing page for pSnapper too). Details here: (you may want to wait an hour before playing the videos, to give youtube time to encode higher resolution videos)

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Tanel Poder 🇺🇦

@TanelPoder

5 years

Check out what just arrived! (Mastering Oracle Trace Data v3 by Cary Millsap): /cc @CaryMillsap @MethodR

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Tanel Poder 🇺🇦

@TanelPoder

5 years

Oracle RAC 19c Technical Architecture:

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Tanel Poder 🇺🇦

@TanelPoder

6 years

Moving in to a new home (Miami Beach ;-) The most important part is done. Now need to think about getting my furniture and stuff.

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Tanel Poder 🇺🇦

@TanelPoder

5 months

Whoa, here goes my (another) weekend! Accidentally stumbled upon Magic Trace by @trishume that uses Intel Processor Trace and can report you about 10ms of activity that happened *before* you ended up in the traced/offending function or event!

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Tanel Poder 🇺🇦

@TanelPoder

4 years

Thanks for retweeting my hacking session question!!! Due to popular demand, I will run 2 different sessions in January, here's the first: "What are Oracle instance State Objects and How to Read System State Dumps" Wed, Jan 8, 2020 12:00pm-1:30pm EST

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Tanel Poder 🇺🇦

@TanelPoder

5 years

I published a description & ToC of my new "Practical Linux Performance and Application Troubleshooting" training class (starting on 29th April). We'll systematically troubleshoot both at system-level and do drilldown at application process/thread-level!

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Tanel Poder 🇺🇦

@TanelPoder

7 years

In case you missed it: I'm running my Advanced Oracle Troubleshooting online training once more in Jan/Feb 2018! We'll go very deep! :)

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Tanel Poder 🇺🇦

@TanelPoder

5 years

There's so much new stuff (including new background processes) added in Oracle 12.2, 18, 19, so I'm just reviewing this "architecture introduction" myself and have learned new stuff in 2 minutes already!

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Tanel Poder 🇺🇦

@TanelPoder

10 months

So, Oracle will co-locate Exadatas in Azure cloud regions now. Should help to lower Azure app-server <-> Database communication latency (over the previous direct link solution). "Oracle Exadata Database Service will be the first available product in this offering."

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Tanel Poder 🇺🇦

@TanelPoder

4 months

Introducing bpftop: bpftop provides a dynamic real-time view of running eBPF programs. It displays the average execution runtime, events per second, and estimated total CPU % for each program.

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Tanel Poder 🇺🇦

@TanelPoder

5 years

The Future of Database Management Systems Is Cloudy - Donald Feinberg

Gartner Business Insights, Strategies & Trends For Executives

Dive deeper on trends and topics that matter to business leaders. #BusinessGrowth #Trends #BusinessLeaders

www.gartner.com

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Tanel Poder 🇺🇦

@TanelPoder

6 years

Bought some holiday reading. End-to-end computer performance knowledge starts from electrical signals ;-P

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Tanel Poder 🇺🇦

@TanelPoder

6 months

Finally got my hands on all translations of the OG Expert Oracle Exadata book! 🙂

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Tanel Poder 🇺🇦

@TanelPoder

6 years

Ok, I ended up re-recording the whole video due to the PowerPoint crashes when doing this live. Here's the recording:

Troubleshooting a Complex Oracle Performance Issue

In this session Tanel will walk you through troubleshooting a yet another complex performance issue that he has faced in past. Again, the initial symptoms po...

www.youtube.com

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Tanel Poder 🇺🇦

@TanelPoder

6 years

PKG_XDOLLAR_SEARCH - Search in all X$ tables - DBA - Rodrigo Jorge - Oracle Tips and Guides

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Tanel Poder 🇺🇦

@TanelPoder

7 years

"Soon, I will post about a cool free tool that automates the implementation of SQL Plan Management on a high-rate OLTP where stability is more important than flexibility" - Looking forward to that!

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Tanel Poder 🇺🇦

@TanelPoder

5 years

Looks like @OracleSK wants to drink my beer #tvdpdays

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Tanel Poder 🇺🇦

@TanelPoder

9 days

New Process Watch Linux tool (based on snapshots of per-process CPU performance counter deltas). Useful for low level efficiency & troubleshooting things...

Ben Olson

@benbenolson1

2 years

Just released a new open-source profiling tool. Have you ever wondered if you can get per-process instruction mix? Well, with eBPF, now you can! Let me know what you think; still an active work-in-progress.

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Tanel Poder 🇺🇦

@TanelPoder

1 year

Oracle's "Understanding Shared Pool Memory Structures" paper from 2005 is still relevant if you want to keep up w the modern Oracle shared pool heap implementation:

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Tanel Poder 🇺🇦

@TanelPoder

6 years

A little Oracle CBO troubleshooting hack with vim - rename an optimizer trace file from .trc to .sql (or use :set syntax=sql) to get reasonable syntax highlighting of the CBO calculation sections too (makes reading the traces a little more bearable).

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Tanel Poder 🇺🇦

@TanelPoder

5 years

Red Hat Enterprise Linux 8 released

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Tanel Poder 🇺🇦

@TanelPoder

5 months

What's Inside a Linux Kernel Core Dump It also mentions the Python-based debugging library "drgn": Dealing with kernel things is easier if you code your troubleshooting path with drgn, instead of mucking around with "crash".

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Tanel Poder 🇺🇦

@TanelPoder

5 years

This Oracle bug sounds promising (for fun & troubleshooting): Bug 30158313 : DATABASE INSTANCE CRASHES WHEN SETTING SQL_TRACE IN CDB AND PDB

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Tanel Poder 🇺🇦

@TanelPoder

1 year

JVM Field Guide: Great article about analyzing Java/JVM memory allocation & usage:

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Tanel Poder 🇺🇦

@TanelPoder

6 years

Reminder - I'm doing my Advanced Oracle Troubleshooting v3.0 online traning later this month, starting on 26. Nov. Have new scripts, demos of complex troubleshooting scenarios, plus 12.2+18c stuff! Downloadable personal videos before/after the class too!

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Tanel Poder 🇺🇦

@TanelPoder

6 years

Learned something new today (from @AndrewSayer_ blog) about sqlplus 12.2. You can define bind variables *and* assign values to them with all sqplus syntax, previously had to "EXEC :bind = value" too.

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Tanel Poder 🇺🇦

@TanelPoder

1 year

Undo logs in Postgres: PostgreSQL: No More VACUUM, No More Bloat

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Tanel Poder 🇺🇦

@TanelPoder

5 years

Time to learn a new SQL dialect ...

AWS Open Source

@AWSOpen

5 years

Announcing PartiQL, one query language for your relational and non-relational data:

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Tanel Poder 🇺🇦

@TanelPoder

5 years

Traveling, Speaking, Training, Gluent and What I'm Up To (in 2019)

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Tanel Poder 🇺🇦

@TanelPoder

6 years

I’m waiting for Oracle to rewrite their SQL Monitoring report in HTML5. And then for every customer to upgrade to Oracle 19c or whatever version this will get put in. Should happen in my lifetime I hope.

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Tanel Poder 🇺🇦

@TanelPoder

2 months

Diagnostics + Tuning pack access is enabled (by default) in the new free Oracle 23ai release (IIRC, previously it was disabled by default)

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Tanel Poder 🇺🇦

@TanelPoder

6 years

Just published a little script sqlmon_restarts.sql for finding UPDATE/DELETE statements that hit the write consistency issue & have to restart under the hood: (it uses V$SQL_PLAN_MONITOR, so requires Diag+Tuning pack licenses)

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Tanel Poder 🇺🇦

@TanelPoder

5 years

@lukaseder To make life easier for developers (so that they’d never have to talk to a DBA again), store this data as a table in an Excel file. Then persist the Excel file as a BLOB in the DB. You’ll need locking to make sure that only one transaction can check out the file at a time

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Tanel Poder 🇺🇦

@TanelPoder

4 years

New blog: Oracle fatal background processes

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Tanel Poder 🇺🇦

@TanelPoder

6 years

Found and interesting GitHub repo with Oracle VLDB features code & trace examples, maintained by @vldbb

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Tanel Poder 🇺🇦

@TanelPoder

6 years

In case you missed it: I'm running an Advanced Oracle Troubleshooting case study webinar on Tuesday Jun 12, 2018 12:00 PM EDT. It's complex, educational & fun! Some systematic troubleshooting method stuff too! Register:

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Tanel Poder 🇺🇦

@TanelPoder

4 years

New post: Oracle Shared Pool Internals: List Chunk Position in the LRU List

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Tanel Poder 🇺🇦

@TanelPoder

5 years

As expected, I couldn’t help it👇 Sorry, all the folks who still have to manage with only 32 GB of RAM in their laptop.

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Tanel Poder 🇺🇦

@TanelPoder

5 years

Ok pSnapper v0.13 released with kstack support! There's also a changelog file in the repo now. ./psn --list will list all currently possible reporting columns. You see we have a lot of work (and fun) ahead!

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Tanel Poder 🇺🇦

@TanelPoder

4 years

This is my version /cc @GeraldVenzl

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Tanel Poder 🇺🇦

@TanelPoder

7 years

Bought some holiday reading! :)

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