Experiment 1: Explicitly commit IndexedDB write transactions

[stopachka]

Problem

If you background a tab in android, sometimes it causes active tabs to freeze

Reason

We open a transaction on IndexedDB when we save pending mutations. If Chrome decides to freeze while the tx is open, all other transactions to IndexedDB will be blocked, waiting for that transaction

Solution

Unfortunately there is no easy way to tell IndexedDB to time out when we are sending a tx.

But one thing we can do is to commit the transaction faster:

We call IDBTransaction.commit() after setItem, multiSet, and removeItem right away.

This lets IDB commit the transaction, before having to send back a "done" result to our callback.

When running tests, this reduced the number of noticed blocks from 4/6 to 1/6

Detailed explainer: https://instant-frozen-tab-idb.stopa.chatgpt.site

Future Work

This still may not be enough. It's still possible that we try to do a very large write (with lots of pending mutations), and just at that moment Android freezes us.

To avoid this, we would have to start saving each transaction as a separate row, so we could start to bound writes to pendingMutations.

This may be a bit more involved, so I wanted to first ship this version, before experimenting with a full on rewrite.

@dwwoelfel @nezaj

[coderabbitai]

No actionable comments were generated in the recent review. 🎉

ℹ️ Recent review info

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Configuration used: Repository UI

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Run ID: c7273bd0-3f20-4b2d-801e-55c5895ba293

📥 Commits

Reviewing files that changed from the base of the PR and between 647e3aa and a5a460e.

📒 Files selected for processing (1)

• client/packages/version/src/version.ts

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📝 Walkthrough

Walkthrough

IndexedDBStorage now explicitly commits supported write transactions for setItem, multiSet, and removeItem. Tests verify commit calls and stored values. The shared package version changes to v1.0.64.

Changes

IndexedDB transaction commits

Layer / File(s)	Summary
Storage transaction handling client/packages/core/src/IndexedDBStorage.ts, client/packages/core/__tests__/src/utils/PersistedObject.test.ts	Write operations call the optional commit method. Tests verify three commit calls, stored values, and spy cleanup.
Package version update client/packages/version/src/version.ts	The shared version changes from v1.0.63 to v1.0.64.

Estimated code review effort: 2 (Simple) | ~10 minutes

Suggested reviewers: nezaj

🚥 Pre-merge checks | ✅ 5

✅ Passed checks (5 passed)

Check name	Status	Explanation
Description check	✅ Passed	The description clearly explains the IndexedDB transaction problem, the explicit commit solution, observed results, and future work.
Title check	✅ Passed	The title clearly and concisely describes the primary change: explicit commits for IndexedDB write transactions.
Docstring Coverage	✅ Passed	No functions found in the changed files to evaluate docstring coverage. Skipping docstring coverage check.
Linked Issues check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Out of Scope Changes check	✅ Passed	Check skipped because no linked issues were found for this pull request.

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[coderabbitai]

🧹 Nitpick comments (1)

client/packages/core/__tests__/src/utils/PersistedObject.test.ts (1)

432-439: 🎯 Functional Correctness | 🔵 Trivial | ⚡ Quick win

Assert one commit per write helper.

The aggregate assertion at Line 439 does not prove that setItem, multiSet, and removeItem each call commit() once. For example, two calls in one helper and no call in another would still pass. Clear the spy and assert one call after each awaited helper.

Proposed test adjustment

     await idb.setItem('key1', 'value1');
+    expect(commitSpy).toHaveBeenCalledTimes(1);
+    commitSpy.mockClear();

     await idb.multiSet([
       ['key2', 'value2'],
       ['key3', 'value3'],
     ]);
+    expect(commitSpy).toHaveBeenCalledTimes(1);
+    commitSpy.mockClear();

     await idb.removeItem('key3');

-    expect(commitSpy).toHaveBeenCalledTimes(3);
+    expect(commitSpy).toHaveBeenCalledTimes(1);

🤖 Prompt for AI Agents

Verify each finding against current code. Fix only still-valid issues, skip the
rest with a brief reason, keep changes minimal, and validate.

In `@client/packages/core/__tests__/src/utils/PersistedObject.test.ts` around
lines 432 - 439, Update the test around setItem, multiSet, and removeItem to
clear commitSpy before each awaited helper, then assert it was called exactly
once immediately afterward. Remove the aggregate commitSpy assertion so each
write helper’s individual commit behavior is verified.

🤖 Prompt for all review comments with AI agents

Verify each finding against current code. Fix only still-valid issues, skip the
rest with a brief reason, keep changes minimal, and validate.

Nitpick comments:
In `@client/packages/core/__tests__/src/utils/PersistedObject.test.ts`:
- Around line 432-439: Update the test around setItem, multiSet, and removeItem
to clear commitSpy before each awaited helper, then assert it was called exactly
once immediately afterward. Remove the aggregate commitSpy assertion so each
write helper’s individual commit behavior is verified.

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ℹ️ Review info

⚙️ Run configuration

Configuration used: Repository UI

Review profile: CHILL

Plan: Pro Plus

Run ID: 132c8cb6-2b2c-4189-9f50-8f1f37bc9699

📥 Commits

Reviewing files that changed from the base of the PR and between c14e0c0 and 647e3aa.

📒 Files selected for processing (2)

• client/packages/core/__tests__/src/utils/PersistedObject.test.ts
• client/packages/core/src/IndexedDBStorage.ts

🚧 Files skipped from review as they are similar to previous changes (1)

• client/packages/core/src/IndexedDBStorage.ts

[github-actions]

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[dwwoelfel]

Cool!