Rohan makes compilers better 🛠️🚀
@rohan_devarc
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Database & Compiler architect | BLAS | HTAP | C++ | FPGAs and other cool electronic circuits
Joined June 2022
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Finally got LiteX as well as UART working on Tang Primer 25K with Linux. Sipeed example repo is not helpful. Some examples don't work on the board.
- Had to fix driver for FT2232 so usb/jtag multiplexing can work properly.
- Firmware has many bugs wrt UART. It's producing
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🚨Trigger Warning: Exercises and solutions have some errors. Some exercises even have wrong answers. Don't trust sections that mention MMU.
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Read this to to your children, it has some cool bed time stories about green and red dragons.
(Yes, even a 6th grader can build a compiler in 2 weeks)
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@MrSinha_
Linguistic chauvinism is a medal of honor for Dravidar Kazhagam. In a culturally literate state, people accept a common link language. However, such a kind of literacy goes against their practices of tribalism.
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All main memory workloads eventually end up being bottlenecked by throughput of a DRAM. This further causes bad perf metrics which are reflected in CPU memory stalls.
A master class in performance engineering!
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Leave the realm of the database/compilers!
They already have people that are more skilled in their craft than you could ever be as a novice.
Rather start learning hardware!
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Found this amazing prof-
MIT 6.824 Distributed Systems (Spring 2020)
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Pretty great resource for FPGA HLS as RTL tend to become very complex for big applications.
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@theskindoctor13
Fine till now. He must bring FDI or it would be tough for MP to break $1700 GDP per capita.
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This book of "singleton patterns" has taught me to never write a interpreter this way!
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@shantanugoel
All pillars of democracy should declare their assets. Lets start with saint peters and his sons.
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Modern CPUs are very abstract.
If you deal with query optimizers for data plane, its one thing to assume selectivity estimates can help, but note that fancy micro-optimization to influence branch prediction surely won't help.
Compiler folks can help -
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Reading some light stuff on weekend
Prince of Persia was a great video game that got me hooked to video games. This book however is more of a journal that the author is maintaining as he develops the game over years.
If you appreciate art like me, then this book is for you.
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This looks comparable to what the CMU DB course provided for a btree visualizer. As always,
@PlanetScale
delivers excellent content.
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It's a beautiful day today! let's expose some misconceptions with hard facts. Relevant for
#developers
and SREs.
Stay tuned for the thread🧵...
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Amazing work by team
@Vicharak_In
. In addition to creating a superb board - VAAMAN, they also took feedback and improved software stack for notably the high speed CPU-FPGA link.
This CPU-FPGA link improves the FPGA experience by allowing you to create custom protocols on the fly
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That's why everyone should take legacy hardware and write a C compiler for it. Bare metal provides deep insights beyond textbooks.
Feeling tired? read this instead -
@rohan_devarc
I am confused with memory alignment - "The address of the memory your data resides in needs to be divisible by the number of bytes required by the instruction/data.
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Yeah, but then author rewrote all assembly code into C++ for AoE Definitive Editions.
This is more about compilers being shitty than magic of assembly.
Same goes with "xyz tycoon"-
Think Assembly code is useless to learn?
Age of Empires I+II used ~13,000 lines of x86 32-bit assembly code.
"The use of assembly in the drawing core resulting in a ~10x sprite drawing speed improvement over the C++ reference implementations, and AoE's drawing core was notably
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Must read🚨
SIEVE, an alternative to LRU eviction algorithm.
Paper link -
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It's not surprising that workplace politics compel skilled engineers to resign.
What relationship does a tech podcast have with a company's commercial practises?
This is "cancel culture" driven by personal vengeance.
"Over application of cancel culture is a cancer culture"
I do not have any time for any e-lafdas; so please do not drag me into one.
I am busy with coding, learning, and becoming a better engineer. 4.3k contributions in the last 365 days working on projects and prototypes that I love.
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In my career, I've learnt to use dense benchmarking strategies for Database testing. I still remember asking my CTO "How do I test for ACID? Is our DB good enough with BASE? Shall I start with I/O perf? Shall I use TLA+?"
Here
@duckdb
's strategy is a good starting point, if your
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Even Turkish people are not afraid of calling out barbaric Mughal/Mogul occupation.
Don't know what dark soul has swept our own country men that they deny civilizational justice to their own people.
Jai Shree Ram🕉️🏹
In the Indian city of Ayodhya, the country’s Prime Minister Narendra Modi is preparing to inaugurate a vast Hindu temple.
The site of the temple was once that of the Babri Masjid, a 16th century mosque, built during Muslim Mughal rule that occupied India from the early 16th to
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The alternative to clean code: no nonsense, no unnecessary abstractions!
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RAM capacity of modern servers enables the storage of the entire database in memory. If you're coming from this idea, then you're taking an easy way out by keeping all workloads main-memory resident.
There is a technique called "anti-caching" which puts data into main memory and
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This will persist despite shifts in the software industry.
- Modeling engineering problems with Applied Math.
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Ofc, now you know the reason why he is going bald!
Btw write a compiler for 8-bit PIC devices to know C better. This is pretty much doable given limited ISA, memory and public datasheets.
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I bet future of software industry on two things -
1) Compilers - They do two things they represent things and transform them. Hence there's a lot of things that end up being compilers.
2) EDA tools - SaaS offering has great potential to roll out a unified tool.
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@Chopsyturvey
This is CGI. There is no such thing in Chennai.
Yet another vannila reality video for propaganda by Dravidian parties.
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io_uring support in libuv
That means Nodejs soon will have a 8x bump in throughput.
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There he goes.....on weed again!
How can a Renesas H8/3644 series microcontroller chip, which has no wireless or network capabilities and no ADC capabilities, get hacked?
Unless there is a transnational attack on chip manufacturing unit, counter-argument is complete bunkum!
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Years ago, my late father and his engineering team visited a notable sitting Congress MP to settle concerns with an ongoing project. The Congress MP refused to listen to any demands, instead replied blatantly - "We don't win because of your vote, we win....". And since then, we
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"SCNAVM", or abstract machine, the stated formalization model in a nutshell.
I will, unfortunately, have to disappoint you:
C is a High Level Language that compiles to an Semantically-Constrained, Nondeterministic, Abstract Virtual Machine (SCNAVM) that is then projected and modeled onto ${TARGET_PLATFORM}.
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🚨 A fresh approach to resurrecting the forgotten craft of engineering through tech documentaries.
@arpit_bhayani
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Writing your own OS is awesome.
Building your own cpu core is also awesome.
Writing your own compiler is awesome
Writing your own database is also awesome
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Finally no geeks-for-geeks in search results-
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Those celebrating death of innocent israeli citizens should be educated on humanity's core principles.
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Ace hardware design before its too late!
It is unclear whether AI will replace you, but this person will undoubtedly replace you.🧵
I've spent the past ~2 weeks trying to make a chip from scratch with no prior experience. It's been an incredible source of learning so far.
Progress tracker in thread (coolest stuff at the end)👇
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🚨Don't buy!!
Pro buying tip: Never trust the book which doen't have git repository!!!!
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The problem with most DoE folks on tech twitter is that they want to become chad opinion makers, possibly to assert their status outside of the job.
To achieve that they make sure that their opinions should overshadow every else's. Then what follows is ugly exchange due to ego
If you ever see
@championswimmer
retarded mf in Bangalore, give him a tapli on the head, ask why he sh*ts his pants, and block 👍
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@aka_striker
@sagayrajp
@WeDravidians
But unfortunate reality is that he is now being made a hero by "Namma kannadigga" folks.
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Such blatant racism by Canadian/American wignat🇨🇦🇺🇸. Imagine harassing a Polish-Indian couple in Poland with such impunity.
Also, never forget or forgive our dumb Indian women, who have normalized such insults and generalizations against our own men.
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This iranian armed forces guy is holding a ZedBoard with Zynq 7000 FPGA(XC7Z020-CLG484-1). They want to simulate quantum circuits on this FPGA board.
FPGAs are good fit for doing stuff parallelly, and may also be a good fit for emulating qubits. It may be very slow on this
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She deserves a new life and has no legal obligation whatsoever to look after his in-laws.
Even son once married off, no longer obligated to give any of his assets to his parents. His only obligation till he's alive is to give mere bharan-poshan, so his parents won't die of
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Linux Kernel is the most horribly written software.
- `syscall` actually calls `do_syscall`.
- which in turn calls `_do_syscall`. got it?
- and that turns around and calls `____syscall`. which is basically a wrapper for `__syscall`, that's the real thing.
Fuck You LINUS
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These India-China standoffs are pure gem.
"Maa kasam bol raha hu ben..stokes!"😂
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(Assuming read heavy workload)
For 2500 qps, its better to create primary indexes on <uid,eid>. This way high cardinality columns can be optimized for read locks. That justiifes the order in PK.
Absence of "state" in the PK raises a question, but it's reasonable to assume
Picking the right primary key is one of the most important design decisions of your schema; because an optimal key helps you avoid multiple unnecessary secondary indexes.
Here's the schema of one of the production tables. The table
- holds 82GiB data
- has a primary key
- has
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PostgreSQL uses heap-only-tables and puts indexes as separate. A poor configuration for garbage collector would not only bloat the primary data structure on disk but bloat the indexes as well.
`zheap` aims to solve some of those issues!
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LMAO so India did it way before USA, tides are turning for real!
500 drones in Irving, Texas last night showed us that China isn’t the only country where drones are putting fireworks to shame.
This is an incredible sight.
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LMAO complete m0r0ns!😂
This process is known as software testing. Build systems like Bazel provide a remote cache and subsequent remote execution, allowing you to run tests on several systems simultaneously.
An inside view of the notorious IT cell. When you see swarms attacking you, it could be just two or three guys from multiple accounts.
[Representative video]
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@MrAndyNgo
How to divide people in an already war torn state like Manipur?
W̶o̶m̶a̶n̶ ̶
T̶r̶i̶b̶a̶l̶ ̶w̶o̶m̶a̶n̶ ̶
Christian Women
M̶o̶b̶ ̶
T̶r̶i̶b̶a̶l̶ ̶M̶o̶b̶
Hindu Mob
Remember that there are Metei Christians as well as Kuki Christians. This is civil war between tribes.
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Some throw mud at India because they cannot comprehend the civilizational existence of our nation.
This year keep 🇮🇳/engg alive, and appreciate men & women of this soil, be it father of fiber optics Narinder Singh Kapany, or be it any individual alleviating India Inc.
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I love it when rust folks discover actual computer science. coz its a rare sight.
Its almost like another "Look maa!, I discovered integral calculus" moment 🙃.
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@arpit_bhayani
Breaking news🚨
Engineers chose to remain engineers. Clearly, they rather prefer walking through pages in DRAM than sit through board meetings.
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Rust is a replacement for Java, not C++. Rust is not feature complete enough to be even be considered a replacement.
You're better off using golang and C++.
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Angelina Jolie(1995) - "RISC architecture is gonna change everything!" 💯
They also anticipated that how concept of SoC (system-on-chip) with integrated PCI buses will pave the way for the future.
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Compiler literature is somewhat started to get reflected in the present state of tools.
Dynamic Binary Optimization reminds me of LLVM BOLT. While doing RISCV stuff, I stumbled upon how BOLT is being ported to RISCV.
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Amazing stream by
@ajay9470
!
➡️Be it compilers or databases, always concentrate on fundamentals.
➡️ If you're banking on LLVM factory, you would end up getting more confused with compiler mechanics.
➡️ Revisit concepts like control flow graphs to get better at craft.
Do check -
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SPSC queue implementation is still important since it solves several subproblems.
Applying "Lock-Free" everywhere simply because buzzwords must be taken seriously is ridiculous.
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Tinder has become great again!🥳🥳
Systems programming to save the day!
Now my potential throughput is about 100 dates/minute.
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Don't build something from "scratch" merely for the sake of building it. Instead, build products that address challenges.
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It's brutal that
@github
has laid off its entire engineering team in India!
Its time for India to setup its own sophisticated tech companies. Whats the point of brain draining our own nation while west would adopt blanket policy of use and throw?
Never trust your employer
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I never liked how book overused singletons, probably it is done to fit entire code in between the text. It assumes that you're implementing it while you're reading the text.
The positive aspect is that your code will never break and will continue to call singletons (with zero
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Any software - OS/hypervisor implementing synchronization primitives through conditional branches without any serializing instruction on that path, allowing speculative execution is vulnerable to SRC or Speculative Race Conditions.
💀💀
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@ScienceIsDope_
Educate yourself!
Ramayana(Journey of Ram) and Mahabharata(Story of Bhārata dynasty) are literally Itihasas.
Itihasa - इति + हास - ऐसा हुआ था - "It happened!"
Word "history" comes from historicism which has more to do with christianity than with past account of events.
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A swarm of developers creating Javascript for browsers began self-identifying as "full-stack" then were promoted to puncture putras
Puncture putras often summon their inner copycat kid who used to plagiarize college assignments, and there it goes "Update "
What is wrong with people? 🤦♂️
People are spamming a great OSS project like ExpressJS with random README file changes like
- adding their own names,
- adding random links, and
- adding random HTML files
ref:
India already has a really bad reputation,
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A custom distribution around an Android Kernel?? Again IIT Madras with its disgraceful projects conning entire nation.
Last one "a RISC core" was a complete rip off. Anyone can buy $2000 FPGA hardware from SiFive and craft a RISC core on it. Govt is burning cash on IIT Madras🤦♂️
Tested Indian ‘Operating System’ - BharOS developed at
@iitmadras
with
@dpradhanbjp
Ji; A leap forward in PM
@narendramodi
Ji’s
#AatmanirbharBharat
journey.
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🚨Proprietary chip markets have already started looking out for hardware-centric compiler development skills.
LLVM is a compiler-generation framework, however when using proprietary chips, there is a silver lining-
✨"You can escape frontend jungle and work on llvm backend"
@thefossguy
Think bottom up!
-> Database professionals have already shifted their focus to specialized hardware-backed innovation. As a result, capitalize on hardware initially.
-> Compiler folks in recent years, have been working on a proprietary chip from some company. Demand for folks
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C is a lovely language, but before rolling your own vtable, make sure you have well-defined macros so that compiler screams at any illegal cast at compile-time itself.
Other languages are just mid.
And Ben Affleck is also mid.
C is not just a bad language. It is a demonic instrument, that leaves scars on your soul that not even time can heal.
We had a small bug recently where one extension that works with SQLite stopped working with libSQL. One of our engineers,
@iavins
, spent a whole day debugging
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@sarna_dev
...but why when we have this
this
and Linkers and Loaders by Levine.
@SureshK51146910
The book is in a encyclopedia format(breadth first, rather than depth first), you can easily find good books for each one of the chapters. Also, choose titles for a chapter based on modern hardware. Market is full of legacy literature which is not valid any more.
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Wonderful blog by
@richardstartin
!
Also check
@thegeeknarrator
podcast on Pinot .
Remember core performance is deeply rooted with data structures and algorithm. Don't jump to shiny new systems programming languages; just because of PR.
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Bricked my keyboard coz I was playing around with firmware.😭😭
After much profound thinking, I've concluded that my new life goal is to downgrade myself.
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Finally got
@GOWIN_SEMI
GW5AST fpga working with Gowin Analyzer Oscilloscope on linux
It took me few days to fix issues on linux, but windows experience was quite smooth. However if tools were open source it would've been better.
Now I can play with DDR3 and PCIe on
#GOWIN
LitePCIe support for
@latticesemi
CertusPro-NX (Gen3 X4) and
@GOWIN_SEMI
GW5 (Gen2 X4) is coming along nicely! 🚀
We've got MMAP accesses up and running and will focus on MSI(X) and DMA support.
All using the same Linux driver and LiteX integration as the other already
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@Ravisutanjani
LOL! this kannadiga auto wala came from obscure village to Bengaluru for earning livelihood; apparently he don't want any customers.
Irony died million times; he got no customers, so he begged.🙃
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Ab ye post karne ke baad toh bawaal hi ho jaye ga!
waiting for all chewtiya techbros !
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@protosphinx
Kukiland is the CIA's latest pet project to establish a new Christian state in order to keep India and China under control. And their B team needs to support it, so there will be no noise.
There are no protests since the USCIRF, which organizes such protests, is a branch of
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In the days of 128K dial-up modem, the only way to share music was to burn blank CDs, something the Spotify generation will never understand.
With subscription model, it's impossible to physically own music, communism has won and Gen Z losers are still clueless😔
this spotify generation won’t ever get the struggle of this🫶🏻
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ejml is a complete goldmine if you want to explore how matrix algebra is implemened programatically.
In C++ realm, I used to work with Eigen. Intricacies of matrix algebra has close co-relation with most intuitive programming techniques.
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Back then, I wasn't a backend developer; instead, I knew C++ and Scala, I was building non-web-scale applications that typically ran on a limited number of machines/MPI, serving handful of servers.
Arpit's course gave me clarity on scaling my own stuff beyond adhoc use of MPI.
Thrilled to announce that the admissions for my System Design February Cohort are now open ⚡
In the course, we will build systems exactly how they are built and scaled in the real world. Instead of throwing jargon and drawing random boxes, we will brainstorm minute
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🚨 RISC-V enters data centers!
🇫🇷 Scaleway, the rival of AWS launches cloud with RV64GCV RISC-V EM-RV1 instances with Chinese T-Head C910 SoC, 16GB LPDDR RAM, and 128GB eMMC storage for $17/month.
India has to catch up fast or it'll be too late.
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