nbdkit
abseil-cpp
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nbdkit | abseil-cpp | |
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17 | 54 | |
- | 13,917 | |
- | 2.4% | |
- | 9.5 | |
- | 5 days ago | |
C++ | ||
- | Apache License 2.0 |
Stars - the number of stars that a project has on GitHub. Growth - month over month growth in stars.
Activity is a relative number indicating how actively a project is being developed. Recent commits have higher weight than older ones.
For example, an activity of 9.0 indicates that a project is amongst the top 10% of the most actively developed projects that we are tracking.
nbdkit
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Why AWS Supports Valkey
This is correct, but doesn't quite explain why. It's because when you accept contributions from a variety of authors, without using a CLA, then your code base ends up with a patchwork of copyright, making relicensing practically impossible as you have to get buy-in from every author or else determine that author's contributions and remove/rewrite them.
GPL/LGPL are excellent licenses, but this patchwork of copyright can apply for any license you use. For a small project we wrote which was under BSD, we recently had to make a small (non-functional) change to the license, and we got buy-in from all the authors to do this which took quite a long time: https://gitlab.com/nbdkit/nbdkit/-/commit/952ffe0fc7685ea775...
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Disk write buffering and its interactions with write flushes
That second link is wrong, should be: https://gitlab.com/nbdkit/nbdkit/-/commit/a956e2e75d6c88eeef...
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The C++20 Naughty and Nice List for Game Devs
I think an exception might be made for a plain "C-like" struct that doesn't initialize members or contain anything except basic types. In the specific example[0] the code is actually surrounded by extern "C" { ... } so I suppose that the compiler "knows" this is a plain C struct?
[0] https://gitlab.com/nbdkit/nbdkit/-/blob/cd761c9bf770b23f678f...
- Static Analysis Tools for C
- jq 1.7 Released
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The OpenTF Manifesto
We relicensed[1] a project which had 10 contributors, and we got every single one of them to do an Acked-by (by email) which took some weeks. That was the advice from our lawyers. Can't imagine the impossible hassle of doing the same for something like Linux.
[1] https://gitlab.com/nbdkit/nbdkit/-/commit/952ffe0fc7685ea775...
- TIL: You Can Stop Updating Copyright Attribution Years (2021)
- Starting October 19, storage limit will be enforced on all Gitlab Free accounts
- nbdkit: High performance Linux block devices in userspace
abseil-cpp
- Sane C++ Libraries
- Open source collection of Google's C++ libraries
- Is Ada safer than Rust?
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Appending to an std:string character-by-character: how does the capacity grow?
Yeah, it's nice! And Abseil does it, IFF you use LLVM libc++.
https://github.com/abseil/abseil-cpp/blob/master/absl/string...
The standard adopted it as resize_and_overwrite. Which I think is a little clunky.
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Shaving 40% Off Google’s B-Tree Implementation with Go Generics
This may be confusing to those familiar with Google's libraries. The baseline is the Go BTree, which I personally never heard of until just now, not the C++ absl::btree_set. The benchmarks aren't directly comparable, but the C++ version also comes with good microbenchmark coverage.
https://github.com/google/btree
https://github.com/abseil/abseil-cpp/blob/master/absl/contai...
- Faster Sorting Beyond DeepMind’s AlphaDev
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“Once” one-time concurrent initialization with an integer
An implementation of call_once that accommodates callbacks that throw: https://github.com/abseil/abseil-cpp/blob/master/absl/base/c...
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[R] AlphaDev discovers faster sorting algorithms
I wouldn't say it's that cryptic. It's just a few bitwise rotations/shifts/xor operations.
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Deepmind Alphadev: Faster sorting algorithms discovered using deep RL
You can see hashing optimizations as well https://www.deepmind.com/blog/alphadev-discovers-faster-sort..., https://github.com/abseil/abseil-cpp/commit/74eee2aff683cc7d...
I was one of the members who reviewed expertly what has been done both in sorting and hashing. Overall it's more about assembly, finding missed compiler optimizations and balancing between correctness and distribution (in hashing in particular).
It was not revolutionary in a sense it hasn't found completely new approaches but converged to something incomprehensible for humans but relatively good for performance which proves the point that optimal programs are very inhuman.
Note that for instructions in sorting, removing them does not always lead to better performance, for example, instructions can run in parallel and the effect can be less profound. Benchmarks can lie and compiler could do something differently when recompiling the sort3 function which was changed. There was some evidence that the effect can come from the other side.
For hashing it was even funnier, very small strings up to 64 bit already used 3 instructions like add some constant -> multiply 64x64 -> xor upper/lower. For bigger ones the question becomes more complicated, that's why 9-16 was a better spot and it simplified from 2 multiplications to just one and a rotation. Distribution on real workloads was good, it almost passed smhasher and we decided it was good enough to try out in prod. We did not rollback as you can see from abseil :)
But even given all that, it was fascinating to watch how this system was searching and was able to find particular programs can be further simplified. Kudos to everyone involved, it's a great incremental change that can bring more results in the future.
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Backward compatible implementations of newer standards constructs?
Check out https://abseil.io. It offers absl::optional, which is a backport of std::optional.
What are some alternatives?
dattobd - kernel module for taking block-level snapshots and incremental backups of Linux block devices
Folly - An open-source C++ library developed and used at Facebook.
libnbd
Boost - Super-project for modularized Boost
qemu
spdlog - Fast C++ logging library.
transgui - 🧲 A feature rich cross platform Transmission BitTorrent client. Faster and has more functionality than the built-in web GUI.
Qt - Qt Base (Core, Gui, Widgets, Network, ...)
jackson-jq - jq for Jackson Java JSON Processor
EASTL - Obsolete repo, please go to: https://github.com/electronicarts/EASTL
git-filter-repo - Quickly rewrite git repository history (filter-branch replacement)
BDE - Basic Development Environment - a set of foundational C++ libraries used at Bloomberg.