writeFile cannot handle big payloads (~100MB+)

[muhammad-st]

Current behavior

When cy.writeFile is called with 100MB+ of text it hangs forever. also when I try to inspect the websocket in chrome browser (in that case) the whole browser freezes.

Desired behavior

cy.writeFile should either handle big payloads or have some explicit limitations.

Test code to reproduce

describe('big file spec', () => {
  it('should fail', () => {
    cy.visit('https://www.google.com');
    cy.writeFile('./text.txt', 'x'.repeat(100*1024*1024));
  });
});

Cypress Version

8.3.0

Other

tried to use a task and faced the same result, since it seems to be failing to send the serialized args (in case of big payloads).

[jennifer-shehane]

Yah there's something not being handled correctly with writeFile. This is strange considering this used to be the behavior: #3350 So something may have changed.

[walkerburgin]

We're seeing issues with writeFile() and ~100mb files as well (electron, cypress@8.0.0). For us it's manifesting as the Electron process OOM'ing and crashing.

I'm not sure if it's relevant or helpful, but even just creating a similarly sized Buffer will reliably crash the process. This starts failing somewhere in between 100 and 125mb:

describe("Big buffer spec", () => {
    it("should fail", () => {
        console.log(" >>> Big buffer: " + Buffer.from("x".repeat(125 * 1024 * 1024)).length);
    });
});

┌─────────┬───────────────────┬──────────────┬──────────────────────────────────────┬────────────┬────────────────┬──────────┬──────────────┬─────────────┐
│ (index) │       group       │ processCount │                 pids                 │ cpuPercent │ meanCpuPercent │ memRssMb │ meanMemRssMb │ maxMemRssMb │
├─────────┼───────────────────┼──────────────┼──────────────────────────────────────┼────────────┼────────────────┼──────────┼──────────────┼─────────────┤
│    0    │    'Electron'     │      1       │              '1617654'               │    7.17    │       5        │  759.84  │    401.3     │   1180.23   │
│    1    │     'cypress'     │      1       │              '1617118'               │    2.48    │      3.23      │  276.01  │    266.52    │   286.26    │
│    2    │     'plugin'      │      1       │              '1617483'               │     0      │      3.55      │  271.29  │    211.41    │   271.29    │
│    3    │ 'electron-shared' │      4       │ '1617122, 1617303, 1617123, 1617455' │    0.46    │      0.39      │  255.32  │    239.59    │   255.32    │
│    4    │     'ffmpeg'      │      1       │              '1617649'               │     0      │      0.01      │  13.36   │    11.24     │    13.36    │
│    5    │      'other'      │      2       │          '1619759, 1619760'          │     0      │       0        │   3.63   │     3.66     │    3.75     │
│    6    │      'TOTAL'      │      10      │                 '-'                  │   10.11    │     11.03      │ 1579.45  │   1049.46    │   1999.3    │
└─────────┴───────────────────┴──────────────┴──────────────────────────────────────┴────────────┴────────────────┴──────────┴──────────────┴─────────────┘

<--- Last few GCs --->

[1617654:0x382500000000]     9429 ms: Scavenge 600.3 (614.6) -> 592.6 (614.6) MB, 0.2 / 0.0 ms  (average mu = 0.894, current mu = 0.862) allocation failure
[1617654:0x382500000000]     9437 ms: Scavenge 600.3 (614.6) -> 592.6 (614.6) MB, 0.1 / 0.0 ms  (average mu = 0.894, current mu = 0.862) allocation failure
[1617654:0x382500000000]     9444 ms: Scavenge 600.3 (614.6) -> 592.6 (614.6) MB, 0.1 / 0.0 ms  (average mu = 0.894, current mu = 0.862) allocation failure


<--- JS stacktrace --->

[cypress-app-bot]

This issue has not had any activity in 180 days. Cypress evolves quickly and the reported behavior should be tested on the latest version of Cypress to verify the behavior is still occurring. It will be closed in 14 days if no updates are provided.

[cypress-app-bot]

This issue has been closed due to inactivity.