Graph/30303a83-72a8-4605-838f-71a5da538050

Domainunvalidated

Concurrency

30303a83-72a8-4605-838f-71a5da538050

Concurrency

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Public graph metadata

Updated4/30/2026

PageRank0.0007

Effectiveness0.000

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50 linked nodes

Button may be clickable when it should be disabled in onButtonClick

RELATES_TOProblem

too many open database connections — after the update to 4.0. Tension: FATAL: remaining connection slots are reserved for non-replication superuser connections.

PERTAIN_TOProblem

Audio toggle in Next.js is unreliable; it plays the first time but doesn't always pause or resume

PERTAIN_TOSolution

Use useRef instead of a root reference and call play() and pause() through audioRef.current

PERTAIN_TOSolution

set((state) => ({ appSettings: {...state.appSettings, [val]: data} })) — // store.ts. Tension: it has no effect. Outcome: a working code.

PERTAIN_TOProblem

getMessages(channelId) causes an infinite loop when used in Zustand selector

PERTAIN_TOSolution

Use useShallow() around the selector so Zustand can compare the selected result shallowly

PERTAIN_TOProblem

Both `onServerCode` and `onServerRecommendation` have a stale closure over the initial `projectIdStorage` state — socket.on("server_recommendation", onServerRecommendation); socket.on("server_code", onServerCode);. Tension: the server event handlers have the current project id value. Outcome: Update the `useEffect` hook to use a dependency on the `projectIdStorage` value.

PERTAIN_TOSolution

Update the `useEffect` hook to use a dependency on the `projectIdStorage` value — const projectIdStorage = useProjectStore((state) => state.projectIdStorage);. Tension: Both `onServerCode` and `onServerRecommendation` have a stale closure over the initial `projectIdStorage` state. Outcome: so that the server event handlers have the current project id value.

PERTAIN_TOSolution

Make both select inputs controlled components by binding their value to the zustand language state (using `value={language}`) and updating the store on change via the store `set`/action, so both selects re-render and stay in sync.

PERTAIN_TOProblem

Button may be clickable when it should be disabled in onButtonClick

PERTAIN_TOSolution

Add a guard inside onButtonClick that returns early when the button should be disabled

PERTAIN_TOSolution

Use the event value directly for the network call (e.g., `event.value`) or move the dependent side effect to a store subscription/`useEffect` that runs after `sortBy` updates.

PERTAIN_TOProblem

event.value != sortBy — setSort(event.value). Tension: I can't use the state variable inside of this function. It doesn't await, resolve or behave the way I think it will. Outcome: console.log(store.getState().sortBy) // event.value == sortBy.

PERTAIN_TOProblem

As long as you lock more than a single thing at a time, you risk deadlocks. — lock more than a single thing at a time. Tension: You hold B waiting for A, they hold A waiting for B. Outcome: one of you has to abort or you're stuck.

PERTAIN_TOProblem

previous in-flight requests are not cancelled by `injectQuery` — Angular 18 with TanStack Angular Query. Outcome: I searched for a possible workaround, but did not find any.

PERTAIN_TOSolution

Due to availability of `signal` property, we can use it with `fetch API` to achieve this behavior. Tension: previous in-flight requests are not cancelled by `injectQuery`. Outcome: queryFn: ({ signal }) => fetch('https://api.github.com/repos/tanstack/query', { signal: signal, }).then((x) => x.json()),.

PERTAIN_TOProblem

will the next request be initiated 10 seconds after the start of the previous request, or 10 seconds after the previous request completes? — If `refetchInterval` is set to 10 seconds in `useQuery`, and a given request takes 2 seconds to complete. Tension: I looked at the documentation of React Query, but it isn't entirely clear on this point. Outcome: It will be 10 seconds after the previous request completes.

PERTAIN_TOSolution

It will be 10 seconds after the previous request completes. — If `refetchInterval` is set to 10 seconds in `useQuery`. Tension: Understanding the behavior would help me to pick correct `refetchInterval` value. Outcome: The timer re-starts every time when data is put into the cache.

PERTAIN_TOSolution

Add a `placeholderData` method inside config passed to useInfiniteQuery — This method receives the `previousValue`. Tension: useInfiniteQuery does not have this option. Outcome: staleTime: 1000 * 60 * 5, retry: 3.

PERTAIN_TOProblem

If I try to refetch/invalidate I get the RangeError message. — On the first render, the prefetched data comes correctly (as shown in the react-query tools). Tension: So it happens with all the other useFetch I'm using for brevity. Outcome: I have tried to make the fetchFilters a server action, but it will complain that the response is not of a proper format data.

PERTAIN_TOProblem

re-downloading the entire collection every time — a database collection that can be updated by a large number of users in real-time. Tension: the collection is large.

PERTAIN_TOSolution

use a normal `query` and pass `queryClient` into the `queryFn`. Tension: you'll get a query that saves the previous results, fetches any updates whenever the query remounts. Outcome: merges in those updates using whatever merge function you specify.

PERTAIN_TOSolution

As long as you lock more than a single thing at a time, you risk deadlocks. — lock more than a single thing at a time. Tension: You hold B waiting for A, they hold A waiting for B. Outcome: one of you has to abort or you're stuck.

PERTAIN_TOProblem

parallel workers sometimes grab overlapping sets, then wait to mark them as being processed — At the time of item selection, you neither lock them nor check whether they're locked. Tension: someone else could've already grabbed a subset of those. Outcome: duplicate their work on the items they happened to share.

PERTAIN_TOProblem

the cache doesn't work across processes — workers might be pre-forked. Tension: is using lru caching doing what I am expecting, that is - will it only initialize sentry once even though i attempt to do it multiple times? Outcome: provided it's called within the same process.

PERTAIN_TOSolution

provided it's called within the same process — workers might be pre-forked. Tension: the cache doesn't work across processes. Outcome: each process got its own cache.

PERTAIN_TOProblem

if line exists `await startup_consumer()` then there are no logs of `startup_sync_consumer()` and vise a versa — I am running two kafka consummers in fastAPI application. Tension: Looks like each consumer blocks event loop. Outcome: How to fix it?

PERTAIN_TOSolution

spawn it via `asyncio.create_task()` and store the task so you can cancel it on shutdown — Instead of awaiting `consume_messages()`. Outcome: store the task so you can cancel it on shutdown.

PERTAIN_TOProblem

background task blocks eventloop — reload = True or workers > 1. Tension: I immediately get response in my browser and then background task blocks eventloop.

PERTAIN_TOSolution

single worker running async loop. Outcome: So you have a single worker running async loop and you block that loop.

PERTAIN_TOProblem

the background job never runs — my `BackgroundTasks` only execute when declared inside an async dependency. Tension: No exception is raised, the route returns normally. Outcome: If I move the `bg.add_task()` call into the route itself, it works as expected.

PERTAIN_TOSolution

Pass `BackgroundTasks` from the route into your dependency. — when declared inside an async dependency. Tension: the background job never runs. Outcome: async def test_route(bg: BackgroundTasks, data=Depends(dependency)):.

PERTAIN_TOProblem

sqlite3.OperationalError: database is locked. — I trigger `/session_a` and `/session_b` almost simultaneously. Tension: session A reaching commit earlier than session B, but session B is already holding the write lock. Outcome: A will inevitably fail with a database is locked error.

PERTAIN_TOSolution

If you convert all operations to perform asynchronously (using `aiosqlite`) , the issue will be mitigated. — When a route in FastAPI is listed as asynchronous (`async def`). Tension: that doesn't fully solve the inherent single writer problem of Sqlite. Outcome: Here's a fully operational update of the FastAPI server logic:.

PERTAIN_TOProblem

facing error that `event loop is closed` — I have been working on yet another API using FastAPI and trying to write test cases for the APIs. Tension: using `asyncpg` driver/library to connect to the main db and for testcases using `aiosqlite` driver/library. Outcome: re-run the tests and report back on if it mitigates the issue.

PERTAIN_TOProblem

Running the Uvicorn CLI with typical FastAPI arguments (e.g., main:app, --port, --host, --reload) fails with "uvicorn: error: unrecognized arguments". The server launch never starts correctly.

PERTAIN_TOSolution

Avoid letting the application’s argparse parse Uvicorn’s CLI arguments; instead handle your own arguments separately (or create and pass reload/host/port programmatically into uvicorn.run) so Uvicorn receives only its expected parameters.

PERTAIN_TOProblem

I am using FastAPI to make a `GET` request, which runs a `.jar` file that returns some text data. Tension: The Java program takes about `30` seconds to complete and I have attempted to run it asynchronously, but have been unable to.

PERTAIN_TOSolution

Solution 1 — within an `async def` endpoint.

PERTAIN_TORootCause

This prevents blocking the main event loop and freezing the server. — use asyncio.to_thread(). Tension: run the code in a separate thread.

PERTAIN_TOProblem

the `/login/` endpoint hangs indefinitely after the Firestore query using `.stream()` — during development. Tension: Everything works fine in production, but during development.

PERTAIN_TORootCause

query = users_ref.where("email", "==", user.email).limit(1).stream() — @router.post("/login/", tags=["users"]) async def login(user: UserLogin):. Tension: the `/login/` endpoint hangs indefinitely after the Firestore query using `.stream()`. Outcome: the login/ endpoint does not freeze.

PERTAIN_TOSolution

I tried using a `docker-compose` and it worked quite well — I still don't know how to solve this directly from the Dockerfile. Tension: the login/ endpoint does not freeze. Outcome: in fact it returns all valid tokens.

PERTAIN_TOProblem

the two requests are executed "in parallel." — If I make two requests — the first one to the sync endpoint and the second one to the async endpoint — almost at the same time. Tension: I expected the event loop to be blocked. Outcome: the two requests are executed "in parallel.".

PERTAIN_TOSolution

python interpreter just pauses one task and looks at other — In your scenerio where you use asynchronous. Tension: it is not completly usesless. Outcome: Think it like a round-robin.

PERTAIN_TOProblem

If I proxy 6 streams, then my FastAPI app stops accepting any further requests — testing the application through a web browser. Outcome: all subsequent requests would get stalled and queued, until a connection is available.

PERTAIN_TOSolution

Tension: as the browser might be waiting for a response to the previous request from the server.

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