cortex VS ClickHouse

now if its more metric data you are using and want to do APM, prometheus is your man https://prometheus.io/, want to make prometheus your full time job? deploy cortex https://cortexmetrics.io/, honorable mention in the metrics space, Zabbix, https://www.zabbix.com/ I've seen use cases of zabbix going way beyond its intended use its a fantastic tool

Yes, but also no. The Prometheus ecosystem already has two FOSS time-series databases that are complementary to Prometheus itself. Thanos and Mimir. Not to mention M3db, developed at Uber, and Cortex, then ancestor of Mimir. There's a bunch of others I won't mention as it would take too long.

You can use the Remote write feature to send to a centralized location. It would have to be scalable like Cortex https://cortexmetrics.io/

Cortex is not really good for high-cardinality metrics (if you are talking about https://github.com/cortexproject/cortex)

For a homelab I think prometheus + grafana is easy to get started and scales well. There are lots of ways to set up the architecture. Prometheus can write to a directory on a filesystem, it can be set to write to a remote server, and there are other projects to integrate object storage (s3, minio, etc) or influxdb for long term storage and downsampling.

Cortex (it is renamed to Mimir recently).

Disclosure: I work for AWS, but I don't work on the Amazon Managed Service for Prometheus. I have my own very long held opinions about Free and Open Source software, and I am only speaking for myself.

To me, the AGPLv3 license isn't about forcing software users to "give changes back" to a project. It is about giving the permissions to users of software that are necessary for Software Freedom [1] when they access a program over a network. In practice, that means that changes often flow "upstream" to copyleft licensed programs one way or another. But it was never about obligating changes to be "given back" to upstream. In my personal opinion, you should be "free to fork" Free and Open Source Software (FOSS). Indeed, the Grafana folks seem to have decided to do that with Grafana Mimir.

Personally, I hope that they accept contributions under the AGPLv3 license, and hold themselves to the same obligations that others are held to with regard to providing corresponding source code of derivative works when it is made available to users over a network. In my personal opinion, too often companies use a contributor agreement that excuses them from those obligations, and also allows them to sell the software to others under licenses that do not carry copyleft obligations. See [2] for a blog post that goes into some detail about this.

If you look at the Coretex project MAINTAINERS file [3], you will see that there are two folks listed that currently work at AWS, but no other company other than Grafana Labs today. I would love to see more diversity in maintainers for a project like this, as I think too many maintainers from any one company isn't the best for long term project sustainability.

I think if you look at the Cortex Community Meeting minutes [4], you can see that AWS folks are regularly "showing up" in healthy numbers, and working collaboratively with anyone who accepts the open invitation to participate. There have been some pretty big improvements to Coretex that have merged lately, like some of the work on parallel compaction [5, 6].

TL;DR, I think it is easy to jump to some conclusions about how things are going in a FOSS project that don't hold water if you do some cursory exploration. I think best way to know what's going on in a project is to get involved!

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[1] the rights needed to: run the program for any purpose; to study how the program works, and modify it; to redistribute copies; to distribute copies of modified versions to others

[2] https://meshedinsights.com/2021/06/14/legally-ignoring-the-l...

[3] https://github.com/cortexproject/cortex/blob/master/MAINTAIN...

[4] https://docs.google.com/document/d/1shtXSAqp3t7fiC-9uZcKkq3m...

[5] https://aws.amazon.com/blogs/opensource/scaling-cortex-with-...

[6] https://github.com/cortexproject/cortex/pull/4624

> [...] that feed into a prometheus -> cortex store, so I can then map them on Grafana.

I had to Google because I've never heard of any of those. Did I find the right ones?

https://prometheus.io/

https://cortexmetrics.io/

https://grafana.com/

Mine is much more primitive. My indoor temperature monitor is an ESP8266 that uploads the temperature to a simple PHP page that saves it in an sqlite DB. A cron job runs a Perl script every few minutes that extract the data for the last hour, 3 hours, 12 hours, 48 hours, and since the beginning of time and uses gnuplot to produce PNG graphs. There's a static page on my server that displays those graphs.

My outdoor temperature monitor uses a cheap AcuRite 433 MHz indoor/outdoor thermometer I bought. I have an RPi with an RTL-SDR attached spying on the communications between the AcuRite sensor outside and the AcuRite display inside using rtl_433. A script looks at the rtl_433 and finds the AcuRite sensor data and puts it in an sqlite DB. I haven't yet gotten around to making something to graph it.

The nice thing about that approach is that it was also easy to add support for other 433 MHz wireless sensors near me, such as the AcuRite fridge/freezer thermometer I have. I can also see a few assorted sensors of neighbors (temperature, humidity, soil moisture, tire pressure, wind speed, wind direction, rain, and a few other random things). If I wanted to it would be easy to add them to the DB.

When I made a wireless tipping range gauge recently. I used a 433 MHz transmitter module [1] and added a decoder [2] to rtl_433 that understands my data stream format. That gets my data into the rtl_433 output. No need to futz around with 433 MHz receiver modules which appear to be a pain in the ass [3]. An ATTiny85 counts the tips and runs the transmitter. The ATTiny85, the transmitter module, a battery holder, an RJ11 socket because the rain gauge has an RJ11 connector, a board to put those things on [4], and a small waterproof case is pretty much the complete parts list.

I think I'm going to standardize on this general approach. For things that do not have WiFi and only need to report data 433 MHz modules and custom decoders fro rtl_433 on the RPi. For things that do have WiFi, such as any future ESP projects I do, they will just use WiFi to talk to the RPi. If anything needs to get sent outside of my LAN the RPi will handle it.

The RPi is also currently controlling a space heater in my living room, getting connection data from my cable modem periodically and recording that in an sqlite DB, and serving a simple web page that lets me quickly change inputs and volume on my Denon receiver and so I'm already pretty much committed to keeping it running all the time.

[1] https://www.sparkfun.com/products/10534

[2] Decoders can be specified in a simple text file. Here's the one for my rain guage as an example:

  decoder {

Yes, we are working on it! :) Taking some of the learnings from current experimental JSON Object datatype, we are now working on what will become the production-ready implementation. Details here: https://github.com/ClickHouse/ClickHouse/issues/54864

Variant datatype is already available as experimental in 24.1, Dynamic datatype is WIP (PR almost ready), and JSON datatype is next up. Check out the latest comment on that issue with how the Dynamic datatype will work: https://github.com/ClickHouse/ClickHouse/issues/54864#issuec...

In our repository, I've set up a few hard limits: each translation unit cannot spend more than a certain amount of memory for compilation and a certain amount of CPU time, and the compiled binary has to be not larger than a certain size.

When these limits are reached, the CI stops working, and we have to remove the bloat: https://github.com/ClickHouse/ClickHouse/issues/61121

Although these limits are too generous as of today: for example, the maximum CPU time to compile a translation unit is set to 1000 seconds, and the memory limit is 5 GB, which is ridiculously high.

I have a project dedicated to this topic: https://github.com/ClickHouse/ClickBench

It is important to explain the limitations of a benchmark, provide a methodology, and make it reproducible. It also has to be simple enough, otherwise it will not be realistic to include a large number of participants.

I'm also collecting all database benchmarks I could find: https://github.com/ClickHouse/ClickHouse/issues/22398

ClickHouse: A fast open-source column-oriented database management system. ClickHouse is designed for real-time analytics on large datasets and excels in high-speed data insertion and querying, making it ideal for real-time monitoring and reporting.

Today we're going to create an UDF (User-defined Function) in Golang that can be run inside Clickhouse query, this function will parse uuid v1 and return timestamp of it since Clickhouse doesn't have this function for now. Inspired from the python version with TabSeparated delimiter (since it's easiest to parse), UDF in Clickhouse will read line by line (each row is each line, and each text separated with tab is each column/cell value):

For the third, examples here might be analytics plugins in specialized databases like Clickhouse, data-transformations in places like your ETL pipeline using Airflow or Fivetran, or special integrations in your authentication workflow with Auth0 hooks and rules.

Online analytical processing (OLAP) databases like Apache Druid, Apache Pinot, and ClickHouse shine in addressing user-initiated analytical queries. You might write a query to analyze historical data to find the most-clicked products over the past month efficiently using OLAP databases. When contrasting with streaming databases, they may not be optimized for incremental computation, leading to challenges in maintaining the freshness of results. The query in the streaming database focuses on recent data, making it suitable for continuous monitoring. Using streaming databases, you can run queries like finding the top 10 sold products where the “top 10 product list” might change in real-time.

Proton is a lightweight streaming processing "add-on" for ClickHouse, and we are making these delta parts as standalone as possible. Meanwhile contributing back to the ClickHouse community can also help a lot.

Please check this PR from the proton team: https://github.com/ClickHouse/ClickHouse/pull/54870

curl https://clickhouse.com/ | sh

But I continue to find garbage in some of our CI scripts.

Here is an example: https://github.com/ClickHouse/ClickHouse/pull/58794/files

The right way is to:

- always pin versions of all packages;