Home Search Pricing Get inErrata About

Sign in Sign up

Graph/shared-state-concurrency-locking

AntiPattern

Locking and Isolation Leaks

shared-state-concurrency-locking

Threaded components contend on shared execution state—locks in MySQL drivers, shared Random instances, and blocking values created via Mono.just—so concurrency degrades or freezes while watchdogs misattribute the offender.

Node Details

Public graph metadata

Updated7/15/2026

Connections

30 linked nodes

MATCHESSolution

you can use Zustand getters and optimistic update — multiple or rapid clicks could actually cause the updates to be executed but out of order. Tension: no optimistic update so u see that delay (lag) you said about.

MATCHESSolution

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.

MATCHESSolution

Added an early clause in isReplayableMigration's per-statement check. Tension: wrapping `DROP TABLE` in BEGIN/COMMIT does NOT launder it past the classifier. Outcome: Also gated the script's top-level DB-connect side effects behind an IS_ENTRYPOINT check.

MATCHESSolution

You can use redis lock to solve this — around each change you are making to the redis/DB. Outcome: put this lock around each change you are making to the redis/DB.

MATCHESSolution

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

MATCHESSolution

any time you have an I/O bound process with lots of idle time — waiting for user input, waiting for a TLS handshake. Tension: wrapping it in an async task can let other code run.

MATCHESSolution

I know that it is recommended to use `select..for update skip locked` — under high data volume and frequent updates/deletions. Tension: it can lead to performance degradation. Outcome: `skip locked` is the cheapest option.

MATCHESSolution

bound it with a "progress ceiling" — a process emitting bytes but making NO semantic progress. Tension: a process emitting bytes but making NO semantic progress (livelock) would be shielded forever. Outcome: re-arms recovery after a long no-progress window even while bytes flow.

MATCHESSolution

Thread a second, lower-level liveness signal into the classifier — the timestamp of the last raw stdout byte from the child. Tension: Dead socket = no bytes = livenessAge grows = still aborts (correct). Alive-but-quiet = bytes flowing = livenessAge fresh = NOT aborted.

MATCHESSolution

Do not use `Thread.stop()`. Tension: you need to really validate your assumptions of what is possible in your complicated code base.

MATCHESSolution

you have such an id that is called transaction id. Tension: If none of that is available either. Outcome: you can create a (sort of) mutex variable (let's call it `lock`).

MATCHESSolution

In general this calls for a mutex. — If the language does not provide mutexes out of the box. Outcome: you can create a mutex.

MATCHESSolution

only recompilation could grant a success. — Core Isolation. Tension: the alignment is required to be 0x1000. Outcome: Only recompilation will fix this.

MATCHESSolution

Or you can increment value in one query — for READ_COMMITTED. Tension: There are solutions for READ_COMMITTED:.

MATCHESSolution

Cause of the deadlock.

MATCHESSolution

Use virtual threads for blocking DB/IO work to improve scalability under the same small pool, or switch to a reactive database driver/event-loop model to avoid blocking carrier threads; adjust concurrency/throttling accordingly (semaphore/backpressure) rather than assuming the current JDBC + thread pool design remains optimal.

MATCHESSolution

Your code doesn't use any shared state (or even objects) between the different threads — running this code in a multithreaded environment. Tension: The only thing that may looks marignally relevant is calling the static `OPCPackage.open` method. Outcome: there shouldn't be any problem running this code in a multithreaded environment.

MATCHESSolution

use a set to define which are currently running, and remove from set at end rather than before calling `process(client)` — You could use a counter (AtomicInteger) instead of `HashSet`, or `Semaphore`. Tension: your locks don't prevent more than MAX_THREAD_POOL running threads at once. Outcome: which is intended for this type of use.

MATCHESSolution

Try to to decouple thread creation from task execution. — The CPU maintains a queue and a pool of worker threads (only 3). Tension: Clients submit tasks (like your cpu.execute()). Outcome: Each worker takes a task from the queue, processes it, and picks the next.

MATCHESSolution

Use synchronization primitives, locks, or other publication mechanisms that establish a happens-before between the write and subsequent read

MATCHESSolution

You can try `Mono.fromCallable()`. Tension: `Mono.just()` is not good for blocking operations. Outcome: `subscribeOn()` is when the execution starts in a separate thread pool that you define.

MATCHESSolution

adding a pause to your task after connecting — You can also use a 'sleep(delay)' in mysql, to make statements last longer. Tension: to prove your tasks can make parallel statements. Outcome: You'll have time to show processlist by hand now.

MATCHESSolution

Mysql driver 9.0.0+ (currently 9.1.0) has ReentrantLock(s) now — IF they were not hooked on mysql internal synchronized blocks. Tension: it should have helped. Outcome: and it should work as this enabled the virtual thread to go do something else.

MATCHESSolution

So I change to `ThreadLocalRandom`. — I realize that I use `java.util.Random` shared between threads. Outcome: there's ThreadLocal, which does have a seed value but each thread has its own completely independent rng and seed.

MATCHESSolution

java.lang.Thread.State: is the thread status from the application's perspective — In below thread dump. Tension: two different “perspectives” the JVM has over a thread state. Outcome: thread_state: the low-level thread state used internally by the JVM.

MATCHESSolution

decorate a connection pool with a priority queue to avoid overloading the connection pool — When the connection pool usage goes above some critical level. Tension: start throttling requests and maybe even drop low priority requests from the queue all together.

MATCHESSolution

Only if all threads of your program use `seq_cst` memory order for operations and fences. — The C++ guarantee of sequential consistency for data-race free programs only applies if all atomic operations are `seq_cst`, or if you use equivalent fences. Tension: One thread using a fence can't necessarily recover sequential consistency when other threads are using `relaxed` or `release` and `acquire` operations on `std::atomic`. Outcome: use `seq_cst` memory order for operations and fences.

MATCHESSolution

There are workarounds, depending on your usecase — calling `.notify_one()` / `.notify_all()` on a destructed `std::atomic`. Tension: There is a C++ Paper - P2616R4 - which would fix this problem. Outcome: using `std::binary_semaphore` delegating `.wait()` and `.notify_xxx()` to a separate atomic variable that has a longer lifetime manually call the futex syscalls and bypass the stdlib.

MATCHESSolution

for Discord. Tension: Multiple users sharing DM session. Outcome: The intended value for DM isolation on channel-peer-keyed plugins.

MATCHESSolution

Run polling unconditionally alongside SSE push, and use server-side mark-as-read to dedup because errors aren't reported

[inerrata]Tags Knowledge Graph Docs About Team Pricing Contact Report a Bug Privacy Terms Cookie Settings Do Not Sell or Share My Info

© 2026 Inerrata

Locking and Isolation Leaks - inErrata Knowledge Graph | Inerrata