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Reposted by Alfonso Subiotto

Polar Signals @polarsignals.com · Sep 3

We're excited to be at @rustconf.com 2025!
Let's talk about profiling Rust with zero compromise!
#rustconf25

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Reposted by Alfonso Subiotto

Polar Signals @polarsignals.com · Sep 3

We recently made some performance improvements to our Flame Graph by implementing backend pre-computation and viewport culling. Read more in our latest blog post: www.polarsignals.com/blog/posts/2...

Parallel Flame Graph Rendering

How we improved our flame graph rendering by moving computation to the backend.

www.polarsignals.com

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Alfonso Subiotto @asubiotto.com · Aug 26

I wrote about why we should treat German string encoding/StringViews as Just Another Encoding™

Polar Signals @polarsignals.com · Aug 26

German strings 🇩🇪 have become very popular in the database world. However, they're not a silver bullet. Read more in our latest blog post:

Das Problem mit German Strings

And why I don't want my database to choose the best encoding for me (yet)

www.polarsignals.com

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Alfonso Subiotto @asubiotto.com · Aug 22

Thanks for the pointer. Do you know where though? This is what I could find of the representation: github.com/vortex-data/.... Also the pushed-down filter kernel seems to convert to arrow and delegate: github.com/vortex-data/.... In arrow I'm pretty sure the prefixes are not a separate array.

github.com

Alfonso Subiotto @asubiotto.com · Aug 20

Do any database systems "columnarize" the German string encoding so rather than storing a 16-byte view for each element which includes length+prefix+pointer you'd store all lengths together, prefixes together etc...? Seems like prefix operations would be more SIMD friendly.

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Alfonso Subiotto @asubiotto.com · Aug 19

The hardest part about writing a blog post is the introduction. Here I am, 4 hours later.

Reposted by Alfonso Subiotto

Polar Signals @polarsignals.com · Aug 13

Tame the OOM killer with OOMProf, the new eBPF memory profiler for Go programs being taken out by the kernels OOM killer!
www.polarsignals.com/blog/posts/2...

OOMProf - Profiling on the Brink

Using eBPF to record your programs dying breathes

www.polarsignals.com

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Reposted by Alfonso Subiotto

Polar Signals @polarsignals.com · Aug 7

We're excited to share that the Parca Agent now works offline! Store CPU profiles locally when disconnected, upload when ready. Because not all computing happens in data centers.
Read how we built it: www.polarsignals.com/blog/posts/2...

Offline Mode for the Parca Agent

Collect and upload profiles -- even without a network connection

www.polarsignals.com

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Alfonso Subiotto @asubiotto.com · Jul 31

Problem: Everything is JSON. Solution: MORE JSON!

Haha, but thanks for pointing this out. Now I'm going to have to do a little researching

Alfonso Subiotto @asubiotto.com · Jul 31

New storage format RFC in the works 👀 Early preview:

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Reposted by Alfonso Subiotto

Polar Signals @polarsignals.com · Jul 30

🚀 Today, we're excited to launch Off-CPU profiling! Check out our blog on what we needed to do to make it most useful and how you can get started with it! 🧊

www.polarsignals.com/blog/posts/2...

Introducing Off-CPU Profiling

How Off-CPU profiling works and how to get the most out of it

www.polarsignals.com

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Alfonso Subiotto @asubiotto.com · Jul 29

Unfortunately no plans to be in SF around then but we'll keep it in mind in case anyone does end up being there.

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Alfonso Subiotto @asubiotto.com · Jul 18

@metalmatze.de built an MCP server so you can hook up your agent to your profiling data. Check it out!

Matthias Loibl @metalmatze.de · Jul 17

🔥 Have you ever stared at a flame graph wondering why your app is slow?

Using the new @PolarSignalsIO MCP, you can now ask "Why is my service slow?" and e.g. @anthropic.com's Claude Code or @cursor.com.web.brid.gy will analyze your production profiles and suggest code fixes.

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Reposted by Alfonso Subiotto

Polar Signals @polarsignals.com · Jul 8

📔Writing our Rust database from scratch gave us a golden opportunity to implement deterministic simulation testing as a core feature. Learn about the architecture that gives us full control over DST ingredients. 🧊

www.polarsignals.com/blog/posts/2...

Deterministic Simulation Testing in Rust: A Theater Of State Machines

How we designed our database for complete control over concurrency, time, randomness, and failure injection.

www.polarsignals.com

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Alfonso Subiotto @asubiotto.com · Jul 8

I assumed links were downranked everywhere, good to know!

Alfonso Subiotto @asubiotto.com · Jul 8

www.polarsignals.com/blog/posts/2...

Deterministic Simulation Testing in Rust: A Theater Of State Machines

How we designed our database for complete control over concurrency, time, randomness, and failure injection.

www.polarsignals.com

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Alfonso Subiotto @asubiotto.com · Jul 8

Writing our Rust database from scratch gave us a golden opportunity to implement deterministic simulation testing as a core feature. I wrote a blog post about the architecture that gives us full control over concurrency, time, randomness, and failure injection. (link in comment)

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Alfonso Subiotto @asubiotto.com · Jul 7

If you're serious about performance, you need continuous profiling in your life

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Alfonso Subiotto @asubiotto.com · Jul 7

Nice read about how maybe it's time to delete some tests (not your DST test though): andre.arko.net/2025/06/30/y...

You should delete tests

We’ve had decades of thought leadership around testing, especially coming from wholistic development philosophies like Agile, TDD, and BDD. After all that time and several supposedly superseding…

andre.arko.net

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Reposted by Alfonso Subiotto

Chris @chris.blue · Jul 4

This was a fun read. Speed runs building a cloud DB. Hill climbing the design can lead to a local maximum. Lots of lessons. Now I need to read their next post on the new one!

Chris (Links) @links.chris.blue · Jul 2

Best Laid Plans

What we learned from building a database

www.polarsignals.com

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Alfonso Subiotto @asubiotto.com · Jul 4

Looking forward to speaking at @eurorust.eu about the deterministic simulation testing we're doing at @polarsignals.com!

EuroRust @eurorust.eu · Jul 4

Haunted by that one production bug you just can’t reproduce? This talk is for you.

At #EuroRust25, @asubiotto.bsky.social will show how deterministic simulation testing lets you find and replay bugs before they hit prod.

🧵1/3

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Reposted by Alfonso Subiotto

Frederic Branczyk @brancz.com · Jun 20

Our very own @asubiotto.bsky.social for the first time publicly talking about the DST approach we’re taking in our new database.

(Blog post coming soon as well!)

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Alfonso Subiotto @asubiotto.com · Jun 18

www.polarsignals.com/blog/posts/2...

New year new database

Bringing what we've learned to our next generation database.

www.polarsignals.com

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Alfonso Subiotto @asubiotto.com · Jun 18

You know that urge to rewrite your database in Rust? We gave in.

(Link in comment)

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Alfonso Subiotto @asubiotto.com · Jun 18

Off to Systems Distributed. See you in Amsterdam!

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