Limit log batching to maximum 100 logs per batch

[denrase]

📜 Description

This took some digging. I was testing sending logs in a tight loop and got rejected by the backend.

[Sentry] [debug] [1763038665.309155] [SentryRequestOperation:36] Request status: 400
[Sentry] [debug] [1763038665.309175] [SentryRequestOperation:42] Request response: {"detail":"envelope exceeded size limits for type 'log' (https://develop.sentry.dev/sdk/envelopes/#size-limits)"}

So I checked replay code. The issue is that it has 1000 logs MAX item limit, which is not in any documentation we used when implementing the log batching. Its documented here (https://develop.sentry.dev/sdk/telemetry/logs/#buffering)

Another issue I saw during testing is that envelopes persisted with > 1000 log items are being re-tried, so this is something that clients out there may be experiencing.

💡 Motivation and Context

Log envelopes dropped by the backend.

💚 How did you test it?

Unit tests. Sample app.

📝 Checklist

You have to check all boxes before merging:

• I added tests to verify the changes.
• No new PII added or SDK only sends newly added PII if sendDefaultPII is enabled.
• I updated the docs if needed.
• I updated the wizard if needed.
• Review from the native team if needed.
• No breaking change or entry added to the changelog.
• No breaking change for hybrid SDKs or communicated to hybrid SDKs.

Closes #6770

[denrase]

@philipphofmann @noahsmartin I'm thinking if we should also drop individual log item > 1MB or prune large attributes. WDYT?

[codecov]

❌ 1 Tests Failed:

Tests completed	Failed	Passed	Skipped
3926	1	3925	52

View the top 1 failed test(s) by shortest run time

iOS_Swift6_UITests.UITests::testLaunchAndCaptureError

Stack Traces | 0s run time

.../iOS-Swift6/iOS-Swift6-UITests/UITests.swift:11 - Failed to launch <XCUIApplicationImpl: 0x600000d00a20 io.sentry.sample.iOS-Swift6 at .../Products/TestCI-iphonesimulator/iOS-Swift6.app> via Xcode: Timed out while launching application via Xcode.

To view more test analytics, go to the Test Analytics Dashboard
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[cleptric]

Let's please cap this at 100, as in https://develop.sentry.dev/sdk/telemetry/logs/#buffering.
We can always raise limits at a later date, but lowering them is hard.
Yes, Relay technically allows up to 1000 items, but we aligned on 100 across SDKs.

[github-actions]

Performance metrics 🚀

	Plain	With Sentry	Diff
Startup time	1214.73 ms	1243.87 ms	29.14 ms
Size	24.14 KiB	1.01 MiB	1014.03 KiB

Baseline results on branch: main

Startup times

Revision	Plain	With Sentry	Diff
7273bf4	1202.42 ms	1227.62 ms	25.21 ms
8d944ac	1236.92 ms	1254.91 ms	18.00 ms
c6c1cb7	1235.71 ms	1263.80 ms	28.08 ms
a4c5ddc	1239.61 ms	1266.41 ms	26.80 ms
1bf44b4	1238.14 ms	1275.45 ms	37.31 ms
e0e5391	1191.21 ms	1243.14 ms	51.93 ms
7dabfb9	1227.55 ms	1243.94 ms	16.39 ms
cbbc82c	1246.43 ms	1266.13 ms	19.70 ms
aa96485	1215.37 ms	1234.04 ms	18.67 ms
4f36ea5	1216.87 ms	1246.34 ms	29.47 ms

App size

Revision	Plain	With Sentry	Diff
7273bf4	23.75 KiB	908.01 KiB	884.26 KiB
8d944ac	23.75 KiB	919.69 KiB	895.94 KiB
c6c1cb7	23.75 KiB	928.15 KiB	904.40 KiB
a4c5ddc	23.75 KiB	977.30 KiB	953.55 KiB
1bf44b4	23.75 KiB	1021.20 KiB	997.45 KiB
e0e5391	23.74 KiB	1022.21 KiB	998.46 KiB
7dabfb9	23.75 KiB	980.80 KiB	957.05 KiB
cbbc82c	23.75 KiB	995.22 KiB	971.47 KiB
aa96485	23.75 KiB	874.46 KiB	850.71 KiB
4f36ea5	23.75 KiB	995.08 KiB	971.33 KiB

[philipphofmann]

Thanks

[philipphofmann]

Let's please cap this at 100, as in https://develop.sentry.dev/sdk/telemetry/logs/#buffering. We can always raise limits at a later date, but lowering them is hard. Yes, Relay technically allows up to 1000 items, but we aligned on 100 across SDKs.

I also added this as recommendation to getsentry/sentry-docs#15513