How frequently does the bug occur?

Sometimes

Description

I have a database with a very limited amount of used bytes, although the overall file size is well over 50 MB. I expected this database to compacted on launch by using RealmConfiguration.Builder(....).compactOnLaunch(), but that didn't happen.

Checking the documentation of DEFAULT_COMPACT_ON_LAUNCH_CALLBACK, I see this comment:

> The default implementation for determining if a file should be compacted or not. This implementation will only trigger if the file is above 50 MB and 50% or more of the space can be reclaimed.

But it seems that the current implementation is checking if less than 50% can be reclaimed, so the other way around than described in the comment.

Adding the last assertion to the unit test confirms this:

@Test
fun `doCompact test`() = runTest {
    assertEquals(false, LocalStorageInitializer.doCompact(50 * 1024 * 1024, 40 * 1024 *1024)) // not > 50MB and < 50% reclaimable -> should be false
    assertEquals(false, LocalStorageInitializer.doCompact(50 * 1024 * 1024 + 8, 25 * 1024 * 1024)) // > 50MB and > 50% reclaimable -> should be true
    assertEquals(false, LocalStorageInitializer.doCompact(50 * 1024 * 1024 + 8, 25 * 1024 * 1024 + 3)) // > 50MB and > 50% reclaimable -> should be true
    assertEquals(true, LocalStorageInitializer.doCompact(50 * 1024 * 1024 + 8, 25 * 1024 * 1024 + 4)) // > 50MB and >= 50% reclaimable -> should be true
    assertEquals(true, LocalStorageInitializer.doCompact(50 * 1024 * 1024 + 8, 25 * 1024 * 1024 + 5)) // > 50MB and < 50% reclaimable -> should be false

    // adding the following test, more than 50MB filesize and 25 bytes used, should be compacted
    assertEquals(true, LocalStorageInitializer.doCompact(50 * 1024 * 1024 + 8, 25)) // > 50MB and > 50% reclaimable -> should be true
}

Stacktrace & log output

N/A

Can you reproduce the bug?

Always

Reproduction Steps

Use the unit test doCompact test, that currently exists in the codebase.

Version

all versions since https://github.com/realm/realm-kotlin/commit/10acd38d4c3a8dae6c3ed9ba27aeb709df4965bd

What Atlas App Services are you using?

Local Database only

Are you using encryption?

No

Platform OS and version(s)

Android 10+

Build environment

Android Studio version: 2022.2.1
Android Build Tools version: 33.0.2
Gradle version: 7.6.1