omr
multiversion-concurrency-control
omr | multiversion-concurrency-control | |
---|---|---|
4 | 19 | |
931 | 66 | |
0.5% | - | |
9.6 | 7.3 | |
1 day ago | 4 months ago | |
C++ | Java | |
GNU General Public License v3.0 or later | - |
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omr
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A Compiler Writing Playground
Thank you.
There is also OMR
https://github.com/eclipse/omr
but I'm not sure how powerful that is.
I started writing a simple multithreaded interpreter that processes an imaginary assembly. Here's a program in that imaginary assembly that sends integers to other threads and then sends a jump instruction to another thread to jump to some code.
threads 25
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Chibicc – A Small C Compiler
I am interested in this too. I would do different tradeoffs. I am more interested in optional garbage collection, the parallelism and async story in the language such as threading and coroutines or both together.
I suspect combining garbage collection, exceptions, closures, tail call optimisation, parallelism, JIT compilation and coroutines is difficult to do orthogonally.
On eatonphil's discord someone recently shared this link: This is a framework for building high performance language runtimes
https://github.com/eclipse/omr
I am currently implementing a programming language and compiler and interpreter in my multiversion-concurrency-control repository.
https://github.com/samsquire/multiversion-concurrency-contro...
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4 Git Habits & curated list of life-saving articles
Git Crash Course by eclipse/omr project at github.com
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IBM joins Eclipse Adoptium and offers free certified JDKs with Eclipse OpenJ9
I like this part "We continue to employ dozens of developers that work directly and openly in the Eclipse OMR and Eclipse OpenJ9 projects at GitHub. IBM doesn’t produce a separate enterprise version of OpenJ9; we don’t hold back any of the innovation in our runtime."
multiversion-concurrency-control
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Statelines - an idea for representing asynchronicity elegantly
The code is in this repository https://github.com/samsquire/multiversion-concurrency-control in MultiplexingThread.java and MultiplexProgramParser.java
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CRDT-richtext: Rust implementation of Peritext and Fugue
https://github.com/samsquire/multiversion-concurrency-contro...
And I implemented a 3 way text diff with myers algorithm based on https://blog.jcoglan.com/2017/02/12/the-myers-diff-algorithm...
https://github.com/samsquire/text-diff
I implemented an eventually consistent mesh protocol that uses timestamps to provide last write wins
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A collection of lock-free data structures written in standard C++11
I think I lean towards per-thread sharding instead of mutex based or lock free data structures except for lockfree ringbuffers.
You can get embarassingly parallel performance if you split your data by thread and aggregate periodically.
If you need a consistent view of your entire set of data, that is slow path with sharding.
In my experiments with multithreaded software I simulate a bank where many bankaccounts are randomly withdrawn from and deposited to. https://github.com/samsquire/multiversion-concurrency-contro...
I get 700 million requests per second due to the sharding of money over accounts.
- How to get started?
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The “Build Your Own Database” book is finished
If you want some sample code to implement MVCC, I implemented MVCC in multithreaded Java as a toy example
https://github.com/samsquire/multiversion-concurrency-contro...
First read TransactionC.java then read MVCC.java
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Let's write a setjmp
I wrote an unrolled switch statement in Java to simulate eager async/await across treads.
https://github.com/samsquire/multiversion-concurrency-contro...
The goal is that a compiler should generate this for you. This code is equivalent to the following:
task1:
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Structured Concurrency Definition
https://doc.rust-lang.org/book/ch16-00-concurrency.html
I've been working on implementing Java async/await state machine with switch statements and a scheduling loop. If the user doesn't await the async task handle, then the task's returnvalue is never handled. This is similar to the Go problem with the go statement.
https://github.com/samsquire/multiversion-concurrency-contro...
If your async call returns a handle and
- Are there any languages with transactions as a first-class concept?
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Small VMs and Coroutines
yield value2++
https://github.com/samsquire/multiversion-concurrency-contro...
I am still working on allowing multiple coroutines to be in flight in parallel at the same time. At the moment the tasks share the same background thread.
I asked this stackoverflow question regarding C++ coroutines, as I wanted to use coroutines with a thread pool.
https://stackoverflow.com/questions/74520133/how-can-i-pass-...
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Hctree is an experimental high-concurrency database back end for SQLite
This is very interesting. Thank you for submitting this and thank you for working on this.
I am highly interested in parallelism and high concurrency. I implemented multiversion concurrency control in Java.
https://github.com/samsquire/multiversion-concurrency-contro...
I am curious how to handle replication with high concurrency. I'm not sure how you detect dangerous reads+writes to the same key (tuples/fields) across different replica machines. In other words, multiple master.
I am aware Google uses truetime and some form of timestamp ordering and detection of interfering timestamps. But I'm not sure how to replicate that.
I began working on an algorithm to synchronize database records, do a sort, then a hash for each row where hash(row) = hash(previous_row.hash + row.data)
Then do a binary search on hashes matching/not matching. This is a synchronization algorithm I'm designing that requires minimal data transfer but multiple round trips.
The binary search would check the end of the data set for hash(replica_a.row[last]) == hash(replica_b.row[last]) then split the hash list in half and check the middle item, this shall tell you which row and which columns are different.
What are some alternatives?
OpenJ9 - Eclipse OpenJ9: A Java Virtual Machine for OpenJDK that's optimized for small footprint, fast start-up, and high throughput. Builds on Eclipse OMR (https://github.com/eclipse/omr) and combines with the Extensions for OpenJDK for OpenJ9 repo.
electric - Local-first sync layer for web and mobile apps. Build reactive, realtime, local-first apps directly on Postgres.
tesseract-ocr - Tesseract Open Source OCR Engine (main repository)
glibc - GNU Libc
clauf - A C interpreter developed live on YouTube
tree-flat - TreeFlat is the simplest way to build & traverse a pre-order Tree in Rust
ImHex - 🔍 A Hex Editor for Reverse Engineers, Programmers and people who value their retinas when working at 3 AM.
marisa-trie - MARISA: Matching Algorithm with Recursively Implemented StorAge
x64dbg - An open-source user mode debugger for Windows. Optimized for reverse engineering and malware analysis.
pybktree - Python BK-tree data structure to allow fast querying of "close" matches
ClickHouse - ClickHouse® is a free analytics DBMS for big data
abseil-cpp - Abseil Common Libraries (C++)