You can start with all your microservices sharing a single node, add nodes and have the storage layer distributed horizontally in a way transparent to the services themselves.

There no longer is an enterprise version, what runs on Azure is the exact same Citus that you can run yourself. We even invested in Patroni, to make it easier for the community to self-host Citus with HA setups.

While we obviously want people using Citus on Azure, having Citus as a viable open-source choice is our path to achieving that. I wasn't part of the company when the acquisition happened so can't speak to that, but I can imagine how that could have made sales at the transition time unclear.

Personally I would also like to add, that the team is full of long term open-source contributors. We contribute both to PostgreSQL and projects around it (like pgbouncer). I understand and respect your reservation, but wanted to share my perspective on it.

We worked upstream to have `search_path` properly handled (tracked per client) by pgbouncer.

https://github.com/pgbouncer/pgbouncer/commit/8c18fc4d213ad4...

Check config.md in that commit for a verbose, humanized description.

By large and small we are referring to the amount of data each schema holds currently. They can grow over time and some of them may become very big while others will remain small (storage wise).

Comments URL: https://news.ycombinator.com/item?id=36777053

Points: 160

# Comments: 45

> Citus also exists for Postgres but their docs basically tell you that it's only recommended for analytics

Could you point me at the docs that made you think that? We find Citus very good at multi-tenant SaaS apps (OLTP), IoT (HTAP) workloads and analytics (OLAP).

> And it sounds like all it's doing is a basic master-slave postgres setup with quite a few manual things you have to do to even benefit (manually altering tables to make them sharded/partitioned)

This is true for now. We are looking into ways to make onboarding easier. That said, the time spent on defining a good sharding model for your data often leads to very good perf characteristics. Regarding the architecture, I personally find Citus closer in spirit/design to what Vitess is doing. Additionally, every node in the cluster is able to take both writes and reads, so I don't see the parallel to a basic primary/secondary setup.

It is worth to note that the stated problem, of accessing a file after it is closed was addressed in the Phd thesis by [1] Joe Armstrong in which he suggested a solution for exactly this problem by introducing a new testing & development methodology he named "protocol checkers" (9.1 Protocols, page 195). Relevant quote from the thesis:

> Given a protocol which is specified in a manner similar to the above it is possible to write a simple “protocol checking” program which can be placed between any pair of processes.

The protocol is a state machine, which would detect the attempt to write to a file after it was closed.

[1] - https://erlang.org/download/armstrong_thesis_2003.pdf

Comments URL: https://news.ycombinator.com/item?id=31678336

Points: 207

# Comments: 77

- Schedule peer programming sessions, especially with less senior staff. Without the office environment they have less opportunities to grow.

- All meetings should have a note listing all decisions made.

- Promote async communication. Have people describe a problem instead of saying hi and waiting for a reply.

I stopped using multiple browser for exactly that purpose. It actually increases your attack surface. While compartmentalization of browsers helps somewhat against tracking you now have to keep all of them updated. RCE bug in one of them already compromises everything you have on your machine, so having multiple browsers just means the attacker can pick from a wider array of targets.

I assume this has been ported from Windows and later never implemented the ripped out components. That said, I don't know the windows API so apart from confirming that they exist in Windows docs[2] I can't assess how valid their usage was.

[1] - https://github.com/microsoft/omi/commit/edbe231042173018c529...

[2] - https://docs.microsoft.com/en-us/windows/win32/api/dpapi/nf-...

> By a process of elimination, we decided to try writing POSTGRES in LISP. We expected that it would be especially easy to write the optimizer and inference engine in LISP, since both are mostly tree processing modules. Moreover, we were seduced by AI claims of high programmer productivity for applications written in LISP.

> We soon realized that parts of the system were more easily coded in C, for example the buffer manager which moves 8K pages back and forth to the disk and uses a modified LRU algorithm to control what pages are resident. Hence, we adopted the policy that we would use both C and LISP and code modules of POSTGRES in whichever language was most appropriate. By the time Version 1 was operational, it contained about 17000 lines of LISP and about 63000 lines of C.

src: https://dsf.berkeley.edu/papers/ERL-M90-34.pdf

It also had time travel (from the same paper):

> Lastly, POSTGRES supports the notion of time travel. This feature allows a user to run historical queries. For example to find the salary of Sam at time T one would query:

    retrieve (EMP.salary)
    using EMP [T]
    where EMP.name = "Sam"

Regarding your project:

> Databases are implemented as directories containing one file per table.

PostgreSQL splits tables into 1 GB segments (1 segment is one file). This is done for filesystems that can't have large files. Isn't one file per DB too limiting in that regard?

Are you aiming to be ACID compliant? Can you expand on 'versioned'? PostgreSQL achieves that with copy-on-write, did you take the same approach? I quickly looked over the code, it's been a while since I read some lisp. The on-disk representation seems to be just key value records where each record can be a sexp(?). Where is the relational part and do you plan to implement a query language?

In essence, the guy was a micromanager with trust issues. They later replaced him, with someone that was actually worse.

Hope this makes you feel slightly better: https://www.folklore.org/StoryView.py?story=Negative_2000_Li...

It is impossible to measure someones productivity using metrics like commit counts and SLOC. There are times where I don't commit for weeks and provide actual business value by solving direct client issues without even a ticket being present.

At one time at my second IT job, I had a manager reprimand me (yelling over the phone) that I was away from my desk. I was remotely supporting a bank fixing consortium credit contracts (substantial amounts) after a migration. I was told to stop doing that. So, I told the support tech that my 1-up blocked this. He told the people at the bank; this went up the chain at the bank to the main accountants which resulted in a nasty call from the client to the skip manager of my manager. He called me back and asked me to resume what I did almost crying on the phone. Later that year I was selected employee of the year mostly because of that client constantly sending positive feedback on my help.

> A blueprint is a reproduction of a technical drawing or engineering drawing [...] allowed rapid and accurate production of an unlimited number of copies.

and even if no-one reads the definition, the term is in common use. Spies stealing blueprints of weapons in movies / real-life being an immediate example.

On top of that there is a question of billing and refunds in the case of long-term plans being paid up front (eg. one year subscription).