You can go deeper and model a queue as a ring-esque buffer with a write head (can just be a serial id) and a read head. The read head starts at the same place as the write head and advances only up to the write head and no further via nextval(). The main benefit is you now remove the lock contention as many workers attempt to dequeue at once.

The super advanced version of this is pgque - https://pgque.dev/ - but that’s more like Kafka in Postgres. I wouldn’t go there if you don’t know the Kafka model already and you want it.

FWIW I use atuin (https://atuin.sh/) and am reasonably happy with it, especially the infinite capacity & snapiness. Ignoring the sync features, I believe it's also sqlite backed when running in local-only mode.

The readme starts by saying how the author used to use atuin, and why they wrote stinkpot as a less featureful alternative.

AFAIK it is always backed by a sqlite DB. That way the sync just populates the DB and the completion process doesn't care (or wait for) the central source.

So can it run without AI? They promote their own AI on the website and that is really the last thing I want in my Shell

When you measure latency, you’re measuring it based on requests. So in some bucket if you had a request take 2s and a request take 10s, you would say the average is 6s. This answers the question “how long should I expect a single request to take”.

But the articles point is that to the people - it’s not the number of requests that matters - it’s how often they are waiting for them. The question is “how much time am I sitting here waiting?” In that case the 10s request is 5x worse than a 2s request - it takes 5x of the “time spent”.

So you can change the weighing to 1 / 2 2s 1 / 2 10s to 1 * 2/12 & 1 * 10/12 - that gives us 17% and 83%. And the average there is 9.04s.

The difference is the question. If you think about it as road segments, let’s say you have a group of road segments with different lengths. You can ask the “average length of segment” - or you can ask “if you pick a random point among all the segments, how long is the segment that I landed in?” You’re picking very differently there - the second is proportional to the length!

Technically IMO the blog is slightly off - you want to use “mean residual life”. Ie if I pick a random TIME how long do I have to wait for my request to finish. But it’s reasonably close.

This is standard statistics terminology - E(X) is https://en.wikipedia.org/wiki/Expected_value . E_a is presumably Alice's perceived expected value. Var(X) is https://en.wikipedia.org/wiki/Variance . The law of large numbers says the arithmetic average of observations becomes E(X) with enough samples.

I'm pretty sure what the author is saying is:

E(X) =:= \sum_t(t * P(X = t)) is the definition

another important note is P(X^2 = t^2) = P(X = t) - because it's the same distribution.

E_a(X) is a bit sloppy, but consider X_a aka Alice's latency "experience" distribution. The argument is:

P(X_a = t) = t * P(X = t) / \sum_u(u * P(X = u)) - i.e. scale the probability up by t but make it sum to 1.

Then

E(X_a) = \sum_t(t * P(X_a = t)) = \sum_t(t * t * P(X = t) / \sum_u(u * P(X = u))

aka

E(X^2) / E(X)

Then (from wikipedia)

Var(X) = E(X^2) - (E(X))^2

And we get

E(X_a) = (Var(X) + (E(X))^2) / E(X) = E(X) + Var(X) / E(X)

Thanks!

This might speak to the craziness of the gstreamer plugin ecosystem - good/bad/ugly might be a fun maintenance mnemonic, but `voaacenc` is actually in `bad` - not `ugly`. Most plugins you'd want to use aren't in `good`. How are you supposed to actually use "well supported plugins" with gstreamer? Is it just to not use gstreamer at all?

I was recently in the market for one of these! I ended up going with https://github.com/dbohdan/recur due to the nice stdout and stdin handling. Though this has stdout/stderr pattern matching for failures which is nice too!

Cool, I hadn't seen this one yet! Using Starlark is a very good idea. I ended up writing some tiny DSLs to specify certain things like status code patterns and durations; using an off the shelf DSL like Starlark would've saved a lot of effort.

Very nice work!

I am very far from expert, but understood expect: https://linux.die.net/man/1/expect to be the "swiss army knife" for this type of thing.

I'll confess I've never used `expect`, but I think `expect` is for interactive commands. I think if you were going to write retry logic in bash you would pipe it to `grep` and examine the return code. If `grep` doesn't find any matches, it'll exit with a status code of 1.

I'd never heard of the `wish` command shell (discussed briefly in that document) but you can always rely on the Tcl community to find a great pun.

Facebook’s wormhole seems like a better approach here - just tailing the MySQL bin log gets you commit safety for messages without running into this kind of locking behavior.

IMO mermaid is awesome, but for two somewhat indirect reasons:

- There’s an almost wysiwig editor for mermaid at https://www.mermaidchart.com/play . It’s very convenient and appropriately changes the layout as you draw arrows!

- Notion supports inline mermaid charts in code blocks (with preview!) It’s awesome for putting some architecture diagrams in Eng docs.

Obsidian also supports inline mermaid charts in markdown code blocks. One of those features I don't see mentioned much.

LLMs (I use ChatGPT) can take a generic process description, spit out the result in mermaid, which can then be imported and refined in something like draw.io. Yes, you’ll have to correct a few things by hand, but it drastically speeds things up. Last time I check draw.io is supported in obsidian.

I recently tried this, but the import to draw.io did not go well. It imported as a single static image rather an editable diagram. Maybe I did something wrong?

Usually in such cases either copy and paste the error message from draw.io, or screenshot it and upload to chatGPT. It will debug it for you.

There’s also a specific sequence of steps to import mermaid scripts, I don’t remember the menu location by heart, ChatGPT can also give you the steps needed to do this.

github / gitlab too!

Supernotes too!

Github supports inline mermaid charts, too!

I've been starting to include them in my bigger PRs and reviewers really like them.

About Notion, they do indeed support Mermaid, but their included version is quite obsolete and they don’t seems so eager to update it. A shame.

Hugo does this as well.

Agreed - concretely with-redefs forces single threaded test execution. So eg you can’t use the eftest multithreaded mode.

Explicit dynamic bindings are better if you need something like this since those are thread local.

Usually the controversial decision for Clojure code highlighting is rainbow parens. This color scheme is horrific and unreadable (on mobile at least).

I don't like the color scheme, and in some of the snippets I don't understand the correlation, but some of them, I think the structural highlighting is very nice.