Seastar VS unikraft

I used glommio as the async executor (instead of something like tokio), and it is wonderful. For people wondering whether it's "good enough" or to use C++ and seastar (as I have thought about a lot before starting this project), take the leap of faith, it's fast - both in terms of run time and to code.

b) It's proven now e.g Seastar, Glommio that the fastest way to run a multi-threaded application is to have one instance with one thread pinned per CPU core. Then to have fibers/lightweight threads on top handling all of the asynchronous code. Your approach of lots of instances is the slowest so there will be a ton of unnecessary thread context-switching.

The most common example is DPDK [1]. It's a framework for building bespoke networking stacks that are usable from userspace, without involving the kernel.

You'll find DPDK mentioned a lot in the networking/HPC/data center literature. An example of a backend framework that uses DPDK is the seastar framework [2]. Also, I recently stumbled upon a paper for efficient RPC networks in data centers [3].

If you want to learn more, the p99 conference by ScyllaDB has tons of speakers talking about some interesting challenges.

[1] https://www.dpdk.org/.

[2] https://github.com/scylladb/seastar

[3] https://github.com/erpc-io/eRPC

I assume Tokio itself, see e.g monoio or glommio, but also Seastar for C++.

https://core.dpdk.org/supported/ lists supported nics. You're best just reading material from the dpdk website for figuring out roughly what it is. It is used for a lot of different goals. For most web C++ stuff it's mainly used because you can avoid round trips of data passing through the kernel and can reference network data without tons of copying. For an example check out the SeaStar framework, https://seastar.io/, which is under the hood of ScyllaDB.

As this is a Kafka sub, this may be a good opportunity to mention that Redpanda is based on the same framework (seastar) as Scylla. The idea of sharding work to CPU cores turns out to apply very well to the Kafka data model, too!

Seastar which is a thread per core runtime written by the Scylla devs thats used in both Redpanda and Scylla as the underlying runtime. https://github.com/scylladb/seastar

ScyllaDB is, ironically, maybe one of the worst examples the author could have come up with for "abstraction" in the article.

If folks aren't familiar with their work/internal tech, go check out some of their repos like Seastar. They have some of the most talented systems programmers on the planet writing thin veneers over kernel and hardware API's to squeeze every ounce out of performance.

https://github.com/scylladb/seastar

I know it's beside the point, but I just had to share because I thought that was funny

I’ve seen frameworks for c++ (https://seastar.io/) and rust (https://github.com/actix/actix) which support what you’re describing out of the box.

If you're interested in scaling and asynchronous programming in c++ I highly recommend you investigate the SeaStar application framework. You wouldn't build a web service with SeaStar, rather you would build the infrastructure that you would use to build the web service on top of. https://github.com/scylladb/seastar

You should also probably check out Unikraft (https://unikraft.org) , supports many languages/apps, x86/ARM64 and QEMU/Firecracker. Is also able to run an ELF built under Linux as a unikernel (see https://unikraft.org/guides/bincompat). Discord is at https://unikraft.org/discord .

>"For performance-oriented UDP-based apps, much of the OS networking stack is useless:

the app could simply use the driver API, much like DPDK-style applications already do.

There is currently no way to easily remove just the network stack but not the entire network sub-system from standard OSes."

This page is a great read for any current or future OS developer...

Related:

"Unikraft is a fast, secure and open-source Unikernel Development Kit":

https://unikraft.org/

"Unikraft is an automated system for building specialized OSes known as unikernels."

https://github.com/unikraft/unikraft

unikernel is not the same microkernel.

I've found these after some quick googling:

https://unikraft.org/

Check out https://github.com/unikraft/unikraft

Wow, just now seeing this topic. I work for a cloud company hosted in AWS. We started out, Netflix/Spotify style microservices. We were all on ec2 images generate by packer (and later with AWS Image Factory). When Docker hit, we kicked the tires but never did anything with it beyond using it for running unit tests, and later, infrastructure tests. 5 years ago, during a hackathon, our little group began experimenting with Unikernels, or library operating systems. Interestingly enough, these Unikernels were all stripped down BSD kernels. OSv is FreeBSD based, and Rumprun is NetBSD based. Services running in EC2 on Unikernels would spin up and start sending and receiving traffic before the AWS EC2 healthchecks completed. They are blazing fast! Only problem in 2017, was the tooling. It would have taken too much effort to use Unikernals with our infrastructure. As soon as they start making Unikernels that can run Java bytecode like native code, the fate of containerization will be sealed, IMO. We could get basic JVM webservers running on OSv, but not Cassandra, not Kafka, not yet. OSv now runs on Firecracker, but I have not tried it out, yet. Some links if you are interested: OSv: https://osv.io Rumprun: https://github.com/rumpkernel/rumprun We used this tooling during the Hackathon, but doesn't look like it has been touched in 3 years: https://github.com/solo-io/unik Unikraft Unikernel Dev kit: https://unikraft.org/ And don't forget Firecracker running in Kubernetes https://www.weave.works/oss/firekube/ And of course, being a FreeBSD subreddit, let's not forget FreeBSD on Firecracker https://www.daemonology.net/blog/2022-10-18-FreeBSD-Firecracker.html

and Unikraft