Nevin Ahluwalia

full stack engineer , currently helping to make learner
prev buildspace s3, worked on voice cloning and translation software

[Nevin Ahluwalia @Nevinahl]

Qualified for CIUK 2025 Comp in Manchester !!

CIUK is a HPC competition where we will have to tune a cluster to certain specifications.

Pretty crazy given our team knew literally nothing about HPC a month ago

Everything I've learned is attached below

[Nevin Ahluwalia @Nevinahl]

More coming ...

[Nevin Ahluwalia @Nevinahl]

Qualified for CIUK 2025 Comp in Manchester !!

CIUK is a HPC competition where we will have to tune a cluster to certain specifications.

Pretty crazy given our team knew literally nothing about HPC a month ago

Everything I've learned is attached below

[Nevin Ahluwalia @Nevinahl]

What is InfiniBand?

It is a high performance networking technology used in mainly HPC clusters

How does it communicate ?

RDMA -> Remote Direct Memory Access

This network card is crazy as it SKIPS the OS so you can write directly from RAM on one node to another.

[Nevin Ahluwalia @Nevinahl]

Why does distance to memory matter?

It influences bandwidth as it takes more time for data to be sent across a longer distance so it can leave the CPU sitting idle

Its why the L1 - L3 cache is so fast !

[Nevin Ahluwalia @Nevinahl]

What is NUMA ?

NUMA is a memory architecture used in multi-CPU systems where not all memory is equally close to every CPU

-Each CPU has its own local memory
-CPUs can also access remote memory allocated to another CPU but its slower due to interconnect latency

[Nevin Ahluwalia @Nevinahl]

What are cores?

A core is an independent processing unit within a CPU. Each core can fetch , decode , execute and retire its own sequence of instructions effectively acting like a smaller processer within the main CPU chip

[Nevin Ahluwalia @Nevinahl]

What is the Stream Triad?

It is a vector calculations that has a low arithmetic intensity.

This is crucial because then we can isolate whether a HPC is memory bound or not as we know that it is not compute bound , due to its low arithmetic intensity.

[Nevin Ahluwalia @Nevinahl]

Why do we want to optimise for FLOPS/s ?

This allows us to run our supercomputers faster meaning we can train LLMs faster run models and simulations faster , anything arithmetically heavy can be done significantly faster

[Nevin Ahluwalia @Nevinahl]

How are FLOPS/s are capped ?

1. Compute Bound -> The processor cannot execute the instructions fast enough
2. Memory Bandwidth Bound -> The CPU is sitting idle waiting for data to move to it
3. I/O Bound -> Latency is introduced in the system via read write operations

[Nevin Ahluwalia @Nevinahl]

What the fuck is Likwid-Bench?

This was my exact question at first , Likwid-Bench is a test suite of microkernels designed to a host of benchmarks on these HPCs

Why run these benchmarks?

FLOPS/s (Floating point operations per second) is capped in 3 ways

[Nevin Ahluwalia @Nevinahl]

What is HPC?
It refers to using supercomputers to perform extremely large or complex computations that would be too slow on a normal desktop or laptop.

How did we Qualify?
We had to compete in 3 challenges the one I did in my team involved optimising LIKWID and the STREAM TRIAD

[Nevin Ahluwalia @Nevinahl]

Writing all my tasks down for the UGC dashboard
(search ->https://t.co/6IuqA2gQ8K, WIP) makes coding that much more satisfying and almost gamifies it in a way

[Nevin Ahluwalia @Nevinahl]

Supabase has served as the ideal database for managing the data for the backend of the UGC dashboard I am working on

(link to the dashboard landing page,WIP)
https://t.co/6IuqA2gQ8K

Only problem so far is an overwhelming amount of tables to manage any ideas how to deal w this?

[Nevin Ahluwalia @Nevinahl]

The unofficial TikTok api on GitHub , is unbelievable for scraping data on TikTok

Likes shares comments everything it’s on there and it’s implementation was key to the dashboard

[Nevin Ahluwalia @Nevinahl]

Currently working on weekly reports for the UGC dashboard

This will contain all the weekly trends encapsulated into cards that can be clicked through

All I had to do was add timestamp columns to my supabase tables so I could track data changes and hence calculate trends

[Nevin Ahluwalia @Nevinahl]

I am trying to become a better SWE and here is one thing I learnt

Stepping back and questioning the approach when implementing a feature will save days of work

Now instead of wasting days I only waste hours, so I'll take the improvement

[Nevin Ahluwalia @Nevinahl]

@PranavAhl can u comment on my posts u bum you clearly dont get the algo

[Nevin Ahluwalia @Nevinahl]

@PranavAhl w w w w

[Nevin Ahluwalia @Nevinahl]

@PranavAhl W x 3

[Nevin Ahluwalia @Nevinahl]

I am never writing useless git commit messages again

I needed to revert to a previous commit and this is the garbage I have to look through 🤦‍♂️

what even is this....