TSC Regression causing crash (Heap OOM) between version 4.8.4 & 4.9.3 in large project

[whitespine]

Bug Report

When updating typescript within our project from version 4.7.3 to a more recent version, our project began experiencing OOM issues.
Specifically, it is completely unable to build via tsc or even tsc --noEmit.
Ours is a somewhat large project, so I couldn't point to a minimal reproduction (sorry!).
I have 16GB of RAM so I doubt its a "classic" memory error, seems more likely something started infinitely using memory during a version upgrade.

<--- Last few GCs --->

[7915:0x5f6b230]    32781 ms: Mark-sweep (reduce) 2041.6 (2082.5) -> 2040.8 (2083.0) MB, 492.6 / 0.0 ms  (average mu = 0.088, current mu = 0.038) allocation failure; scavenge might not succeed
[7915:0x5f6b230]    33342 ms: Mark-sweep (reduce) 2041.9 (2083.0) -> 2041.1 (2083.2) MB, 556.2 / 0.0 ms  (average mu = 0.047, current mu = 0.009) allocation failure; scavenge might not succeed


<--- JS stacktrace --->

FATAL ERROR: Ineffective mark-compacts near heap limit Allocation failed - JavaScript heap out of memory
 1: 0xb6d470 node::Abort() [node]
 2: 0xa7e0a8  [node]
 3: 0xd46ee0 v8::Utils::ReportOOMFailure(v8::internal::Isolate*, char const*, bool) [node]
 4: 0xd47287 v8::internal::V8::FatalProcessOutOfMemory(v8::internal::Isolate*, char const*, bool) [node]
 5: 0xf24645  [node]
 6: 0xf25548 v8::internal::Heap::RecomputeLimits(v8::internal::GarbageCollector) [node]
 7: 0xf35a53  [node]
 8: 0xf368c8 v8::internal::Heap::CollectGarbage(v8::internal::AllocationSpace, v8::internal::GarbageCollectionReason, v8::GCCallbackFlags) [node]
 9: 0xf1122e v8::internal::HeapAllocator::AllocateRawWithLightRetrySlowPath(int, v8::internal::AllocationType, v8::internal::AllocationOrigin, v8::internal::AllocationAlignment) [node]
10: 0xf125f7 v8::internal::HeapAllocator::AllocateRawWithRetryOrFailSlowPath(int, v8::internal::AllocationType, v8::internal::AllocationOrigin, v8::internal::AllocationAlignment) [node]
11: 0xef37ca v8::internal::Factory::NewFillerObject(int, v8::internal::AllocationAlignment, v8::internal::AllocationType, v8::internal::AllocationOrigin) [node]
12: 0x12b6d6f v8::internal::Runtime_AllocateInYoungGeneration(int, unsigned long*, v8::internal::Isolate*) [node]
13: 0x16e89b9  [node]
[1]    7915 abort      tsc --noEmit

🔎 Search Terms

tsc 4.9 4.9.5 Out of Memory Heap Out of Memory Crash Killed Silent Error
(Am i doing this right?)

🕗 Version & Regression Information

Error began occuring when updating from typescript 4.7.3 to any 4.9.3^ version.
Issue persists into Version 5.1.0-dev.20230303 (nightly at time of testing).
Issue is NOT present in v4.8.4, or any prior version we tried (that satisfied our dependencies, anyways.)

• This is a crash
• This changed between versions 4.8.4 and 4.9.3

💻 Code

Branch state is: https://github.com/Eranziel/foundryvtt-lancer/tree/oom

Was unable to produce a minimally viable reproduction, as the OOM error gives next to no context as to where the issue occurs or why. Sorry. More than willing to provide more investigative information, but I don't really know what there is to provide.

🙁 Actual behavior

It crashes on more recent versions for no clear reason.

🙂 Expected behavior

I'd rather it didn't.

[liuxingbaoyu]

FYI: You can try https://github.com/microsoft/TypeScript/wiki/Performance-Tracing, it helped us locate the problem in #50515.

[whitespine]

FYI: You can try https://github.com/microsoft/TypeScript/wiki/Performance-Tracing, it helped us locate the problem in #50515.

I will attempt this as soon as i have recruited someone with enough ram to run it without crashing :)

[whitespine]

4.8.4 Diagnostic information:

Files:                        1023
Lines of Library:            28146
Lines of Definitions:       218302
Lines of TypeScript:         25936
Lines of JavaScript:             0
Lines of JSON:                   0
Lines of Other:                  0
Nodes of Library:           118224
Nodes of Definitions:       564026
Nodes of TypeScript:        115815
Nodes of JavaScript:             0
Nodes of JSON:                   0
Nodes of Other:                  0
Identifiers:                301992
Symbols:                    865373
Types:                      208799
Instantiations:             365698
Memory used:               909729K
Assignability cache size:    27600
Identity cache size:          4422
Subtype cache size:           7237
Strict subtype cache size:    9428
Tracing time:                0.17s
I/O Read time:               0.06s
Parse time:                  0.96s
ResolveModule time:          0.08s
ResolveTypeReference time:   0.00s
Program time:                1.27s
Bind time:                   0.62s
Check time:                  2.85s
printTime time:              0.00s
Emit time:                   0.00s
Dump types time:             9.03s
Total time:                  4.74s

5.1.0-dev.20230305 Diagnostic information:

Files:                         1029
Lines of Library:             29397
Lines of Definitions:        218302
Lines of TypeScript:          25916
Lines of JavaScript:              0
Lines of JSON:                    0
Lines of Other:                   0
Identifiers:                 302941
Symbols:                    6242486
Types:                       702542
Instantiations:              417693
Memory used:               5496499K
Assignability cache size:     31947
Identity cache size:           4714
Subtype cache size:            5307
Strict subtype cache size:     7579
Tracing time:                 0.08s
I/O Read time:                0.04s
Parse time:                   0.94s
ResolveModule time:           0.09s
ResolveTypeReference time:    0.00s
Program time:                 1.19s
Bind time:                    0.49s
Check time:                  57.68s
printTime time:               0.00s
Emit time:                    0.00s
Dump types time:              7.27s
Total time:                  59.37s

Notably there is an about 5x increase in memory usage, as well as a >5x increase in the "Types" and "Symbols".

Now that I can actually build on v10 there several new errors, most interesting among them the following:

src/module/item/license-sheet.ts:37:23 - error TS2590: Expression produces a union type that is too complex to represent.

The line is ```TS
for (let d of docs as LancerItem[])

    // Find the assoc frame
    for (let et of [EntryType.FRAME, EntryType.MECH_SYSTEM, EntryType.MECH_WEAPON, EntryType.WEAPON_MOD]) {
      let pack = game.packs.get(`world.${et}`);
      if (pack) {
        let docs = await pack.getDocuments({ "system.license": license.system.key });
        for (let d of docs as LancerItem[]) {
          let rank = (d as any).system.license_level as number;
          while (unlocks.length <= rank) {
            unlocks.push([]);
          }
          unlocks[rank].push(d);
        }
      }
    }

Where docs is of type:
docs: StoredDocument<LancerActor | Scene | LancerItem | JournalEntry | Macro | Playlist | RollTable>[].
Here's where "it's a big project" sort of bites us, in that I can't really minimally represent these types here in this comment. Each is a unique class, all with a shared parent class.

Maybe this is indicative of large union types being the root of our problem?

...

Observing the trace, the file src/module/comp-builder.ts is responsible for an entire 53 SECONDS of the total 57 second Check Time. It produces no errors.

Unsure how to proceed from here.

[ritschwumm]

i had a quite similar issue recently after upgrading typescript. i can't remember the details, but it seems the problem was that under some circumstances tsc started creating a lot of types internally when asked to infer the type of a (typewise) complicated function. in the end, writing const foo:FunctionType = (it) => ... instead of const foo = (it:FunctionArgs):FunctionReturn => ... solved the issue. maybe something similar is happening here?

[Raynos]

Ran into this issue myself today on a large project.

[arlyon]

Similar regression on 5.0.2. For me, 4.8.3 is ok.

thanks for the exceptional bug report @whitespine!

[karlhorky]

I guess there's another issue about JavaScript heap out of memory errors over here (about 4.3):

• JavaScript heap out of memory after upgrading to 4.3 #44299

[jakebailey]

This issue specifically mentions a OOM when going from 4.8 to 4.9; if you are experiencing an OOM that isn't explicitly when you go from 4.8 to 4.9, your issue is most certainly different and should be reported as a new issue with its own repro.

[Raynos]

I was able to solve the OOM issue for myself with

NODE_OPTIONS=--max-old-space-size=8192 tsc

[JarekToro]

Since @Raynos solution is really just a stop gap. What is needed to further this ticket. We also have a large project that works fine on 4.8.4 but cant upgrade to 4.9 or 5.0 because tsc gets an OOM error

[JarekToro]

Here is what I have gathered from running some test.
Test Ran with
NODE_OPTIONS=--max-old-space-size=8192 tsc --noEmit --diagnostics --extendedDiagnostics --incremental false
Here is 4.8

Files:                        2979
Lines of Library:            33311
Lines of Definitions:       233669
Lines of TypeScript:         59133
Lines of JavaScript:             0
Lines of JSON:                 943
Lines of Other:                  0
Nodes of Library:           148246
Nodes of Definitions:       723896
Nodes of TypeScript:        250983
Nodes of JavaScript:             0
Nodes of JSON:                2256
Nodes of Other:                  0
Identifiers:                382980
Symbols:                    597111
Types:                      216450
Instantiations:            7252666
Memory used:               684086K
Assignability cache size:   202376
Identity cache size:          3213
Subtype cache size:          12303
Strict subtype cache size:    4719
I/O Read time:               0.11s
Parse time:                  1.95s
ResolveModule time:          0.58s
ResolveTypeReference time:   0.01s
Program time:                3.04s
Bind time:                   1.00s
Check time:                 16.47s
printTime time:              0.00s
Emit time:                   0.00s
Total time:                 20.50s

Here is 4.9

Files:                         2980
Lines of Library:             33853
Lines of Definitions:        233669
Lines of TypeScript:          59133
Lines of JavaScript:              0
Lines of JSON:                  943
Lines of Other:                   0
Identifiers:                 384065
Symbols:                     571900
Types:                     18112640
Instantiations:             7055141
Memory used:               5726426K
Assignability cache size:  10914208
Identity cache size:           3215
Subtype cache size:           11958
Strict subtype cache size:     4719
I/O Read time:                0.15s
Parse time:                   1.72s
ResolveModule time:           0.47s
ResolveTypeReference time:    0.01s
Program time:                 2.65s
Bind time:                    0.79s
Check time:                 199.89s
printTime time:               0.00s
Emit time:                    0.00s
Total time:                 203.33s

I also generated a trace

From looking into the trace. It seems to be stuck in a loop related to the i18next & react-i18next

This is basically the part that loops (if I followed the trace right)

import type { Namespace, TFuncKey } from 'i18next';
import { i18n } from './i18n';

export interface I18nText<N extends Namespace = Namespace> {
  namespace: N;
  keyName: TFuncKey<N>; // <-- TFuncKey seems to be the culprit
}

That lib is for sure complicated typewise. But it worked as it should in 4.8 and breaks compilation in 4.9 and 5.0

Anything else I can provide? @jakebailey