dragonfly VS amzn-drivers

https://github.com/dragonflydb/dragonfly is another option. Not a fork but API-compatible reimplementation.

Our journey will involve leveraging the capabilities of Dragonfly, a highly efficient drop-in replacement for Redis, known for its ultra-high throughput and multi-threaded share-nothing architecture. Specifically, we'll be utilizing two of Dragonfly's data types: Sorted-Set and Hash. These data structures are perfect for handling real-time data and ranking systems, making them ideal for our leaderboards.

2023 has been a year with remarkable advancements in AI capabilities, and at Dragonfly, we are thrilled to power new use cases with our latest release: Dragonfly Search. This new feature set, debuting in Dragonfly v1.13, is a subset of RediSearch-compatible commands implemented natively in Dragonfly, allowing for both vector search and faceted search use cases in the highly scalable and performant Dragonfly in-memory data store.

If you have not heard about Dragonfly - please check it out. It uses - what I hope - novel and interesting ideas backed up by the research from recent years [1] and [2]. It's meant to fix many problems that exist with Redis today. I have been working on Dragonfly for the last 7 months and it has been one of the more interesting and challenging projects I've ever done!

I recently ran across the the license for Dragonfly [1] which has some restrictions (rights reserved), but 5 years after the license date the license switches to Apache 2.0. Basically a timed-limited rights reservation. I don't hate it. I might even contribute to such a project for free.

I would consider something like this: When I release code, it's rights reserved for 5 years, then open-source (and this baked into an irrevocable license). Anyone may use the software for non-commercial purposes. Anyone may contribute, those who contribute will be granted permission for commercial use if I deem their contributions significant enough. Anyone may distribute the software under these terms.

If such a model became popular, I have a hard time imagining it could make things any worse. It might even accelerate open-source development. You might say, "but it's not open-source", fair enough, but we can view it as open-source contribution with a delay. For example, if this model became wildely popular this year, and we saw great progress with this model, then come 2028 we would be flooded with new open-source software and ultimately might be better off than it would have been without this model.

(And this whole thing makes me rethink copyright and patents and how much they really contribute to society. Perhaps they should be shortened?)

[1]: https://github.com/dragonflydb/dragonfly/blob/main/LICENSE.m...

Maybe check out https://www.dragonflydb.io/ It claims to have a full redis implementation.

Amazon (AWS) cloud EC2 instance specific role (Kernel and User space networking, linux OS related). Amazon has it's own network card with it's own linux driver (open source), for user space they use DPDK (open source). https://github.com/amzn/amzn-drivers I've measured the time between calling tcp send in software, and packet leaving the NIC (network card), it is around ~50 microseconds latency, aws also stated in a paper it is around that number. Goals:- Figure out the way to build from source code and load the kernel.- Reduce latency

It means, for example, writing a FreeBSD kernel driver for Elastic Network Adapter (ENA). Both Linux kernel driver and FreeBSD kernel driver is available at https://github.com/amzn/amzn-drivers

Of course, there are.

I was mostly running on AWS. In terms of hardware, for small packets loadtests most systems are constrained on throughput, i.e. number of packets per second. Some systems saturate on interrupts reaching 100% CPU on all cores and some can not even saturate the CPU and you will see that CPU is at 60% but you can not go beyond some limit. Best systems networkwise are c6gn family types. They are also better than other cloud provide. btw, you mentioned hypervisors... About 8 months ago I opened a bug on AWS Graviton team https://github.com/amzn/amzn-drivers/issues/195 - about performance issue they had on their instances at high throughput. Recently they issued the fix. I suspect it was in their hypervisor.

In terms of my software I found many performance bugs at those speeds. For example, using a default allocator is a big no. I use mimalloc for uncontended allocations. In general, you can not use mutexes and spinlocks at those speeds. Those will just cripple the system. Sometimes it can be very annoying since you can not rely on a 3rd party library without carefully analyzing its design. For example, I could not use openmetrics c++ library because it was not performant enough. Even to implement a simple counter, say to gather statistics for INFO command becomes an interesting engineering problem:

https://doc.dpdk.org/guides/nics/ena.html

and:

https://github.com/amzn/amzn-drivers/tree/master/userspace/dpdk/enav2-vfio-patch

Enabling IOMMU on i3 or c5 metal instances is as easy as adding "iommu=1 intel_iommu=on" to /etc/default/grub followed by update-grub, reboot.

I can't get this to work. Everything I update grub and reboot I cannot re-connected via ssh. Also EC2 console fails to get good status.

My config:

Ubuntu 20.04 stock AWS AMI x86 64-bit