**Build scan:**
https://gradle-enterprise.elastic.co/s/b5y5vbatvwffy/tests/:x-pack:plugin:blob-cache:test/org.elasticsearch.blobcache.shared.SharedBlobCacheServiceTests/testFetchFullCacheEntry

**Reproduction line:**
```
./gradlew ':x-pack:plugin:blob-cache:test' --tests "org.elasticsearch.blobcache.shared.SharedBlobCacheServiceTests.testFetchFullCacheEntry" -Dtests.seed=CEAC7E143D9D8854 -Dtests.locale=vi -Dtests.timezone=Cuba -Druntime.java=20
```

**Applicable branches:**
main

**Reproduces locally?:**
No

**Failure history:**
https://gradle-enterprise.elastic.co/scans/tests?tests.container=org.elasticsearch.blobcache.shared.SharedBlobCacheServiceTests&tests.test=testFetchFullCacheEntry

**Failure excerpt:**
```
java.lang.AssertionError: expected:<0> but was:<204800>

  at __randomizedtesting.SeedInfo.seed([CEAC7E143D9D8854:41BA89DFD434327B]:0)
  at org.junit.Assert.fail(Assert.java:88)
  at org.junit.Assert.failNotEquals(Assert.java:834)
  at org.junit.Assert.assertEquals(Assert.java:645)
  at org.junit.Assert.assertEquals(Assert.java:631)
  at org.elasticsearch.blobcache.shared.SharedBlobCacheServiceTests.testFetchFullCacheEntry(SharedBlobCacheServiceTests.java:380)
  at jdk.internal.reflect.DirectMethodHandleAccessor.invoke(DirectMethodHandleAccessor.java:104)
  at java.lang.reflect.Method.invoke(Method.java:578)
  at com.carrotsearch.randomizedtesting.RandomizedRunner.invoke(RandomizedRunner.java:1758)
  at com.carrotsearch.randomizedtesting.RandomizedRunner$8.evaluate(RandomizedRunner.java:946)
  at com.carrotsearch.randomizedtesting.RandomizedRunner$9.evaluate(RandomizedRunner.java:982)
  at com.carrotsearch.randomizedtesting.RandomizedRunner$10.evaluate(RandomizedRunner.java:996)
  at com.carrotsearch.randomizedtesting.rules.StatementAdapter.evaluate(StatementAdapter.java:36)
  at org.apache.lucene.tests.util.TestRuleSetupTeardownChained$1.evaluate(TestRuleSetupTeardownChained.java:48)
  at org.apache.lucene.tests.util.AbstractBeforeAfterRule$1.evaluate(AbstractBeforeAfterRule.java:43)
  at org.apache.lucene.tests.util.TestRuleThreadAndTestName$1.evaluate(TestRuleThreadAndTestName.java:45)
  at org.apache.lucene.tests.util.TestRuleIgnoreAfterMaxFailures$1.evaluate(TestRuleIgnoreAfterMaxFailures.java:60)
  at org.apache.lucene.tests.util.TestRuleMarkFailure$1.evaluate(TestRuleMarkFailure.java:44)
  at com.carrotsearch.randomizedtesting.rules.StatementAdapter.evaluate(StatementAdapter.java:36)
  at com.carrotsearch.randomizedtesting.ThreadLeakControl$StatementRunner.run(ThreadLeakControl.java:390)
  at com.carrotsearch.randomizedtesting.ThreadLeakControl.forkTimeoutingTask(ThreadLeakControl.java:843)
  at com.carrotsearch.randomizedtesting.ThreadLeakControl$3.evaluate(ThreadLeakControl.java:490)
  at com.carrotsearch.randomizedtesting.RandomizedRunner.runSingleTest(RandomizedRunner.java:955)
  at com.carrotsearch.randomizedtesting.RandomizedRunner$5.evaluate(RandomizedRunner.java:840)
  at com.carrotsearch.randomizedtesting.RandomizedRunner$6.evaluate(RandomizedRunner.java:891)
  at com.carrotsearch.randomizedtesting.RandomizedRunner$7.evaluate(RandomizedRunner.java:902)
  at org.apache.lucene.tests.util.AbstractBeforeAfterRule$1.evaluate(AbstractBeforeAfterRule.java:43)
  at com.carrotsearch.randomizedtesting.rules.StatementAdapter.evaluate(StatementAdapter.java:36)
  at org.apache.lucene.tests.util.TestRuleStoreClassName$1.evaluate(TestRuleStoreClassName.java:38)
  at com.carrotsearch.randomizedtesting.rules.NoShadowingOrOverridesOnMethodsRule$1.evaluate(NoShadowingOrOverridesOnMethodsRule.java:40)
  at com.carrotsearch.randomizedtesting.rules.NoShadowingOrOverridesOnMethodsRule$1.evaluate(NoShadowingOrOverridesOnMethodsRule.java:40)
  at com.carrotsearch.randomizedtesting.rules.StatementAdapter.evaluate(StatementAdapter.java:36)
  at com.carrotsearch.randomizedtesting.rules.StatementAdapter.evaluate(StatementAdapter.java:36)
  at org.apache.lucene.tests.util.TestRuleAssertionsRequired$1.evaluate(TestRuleAssertionsRequired.java:53)
  at org.apache.lucene.tests.util.AbstractBeforeAfterRule$1.evaluate(AbstractBeforeAfterRule.java:43)
  at org.apache.lucene.tests.util.TestRuleMarkFailure$1.evaluate(TestRuleMarkFailure.java:44)
  at org.apache.lucene.tests.util.TestRuleIgnoreAfterMaxFailures$1.evaluate(TestRuleIgnoreAfterMaxFailures.java:60)
  at org.apache.lucene.tests.util.TestRuleIgnoreTestSuites$1.evaluate(TestRuleIgnoreTestSuites.java:47)
  at com.carrotsearch.randomizedtesting.rules.StatementAdapter.evaluate(StatementAdapter.java:36)
  at com.carrotsearch.randomizedtesting.ThreadLeakControl$StatementRunner.run(ThreadLeakControl.java:390)
  at com.carrotsearch.randomizedtesting.ThreadLeakControl.lambda$forkTimeoutingTask$0(ThreadLeakControl.java:850)
  at java.lang.Thread.run(Thread.java:1623)

```
x-pack/plugin/blob-cache/src/test/java/org/elasticsearch/blobcache/shared/SharedBlobCacheServiceTests.java
)
            .build();
        RelativeByteSizeValue relativeCacheSize = SharedBlobCacheService.SHARED_CACHE_SIZE_SETTING.get(settings);
        assertThat(relativeCacheSize.isNonZeroSize(), is(false));
        assertThat(relativeCacheSize.isAbsolute(), is(true));
        assertThat(relativeCacheSize.getAbsolute(), equalTo(ByteSizeValue.ZERO));
        assertThat(SharedBlobCacheService.SHARED_CACHE_SIZE_MAX_HEADROOM_SETTING.get(settings), equalTo(ByteSizeValue.ofBytes(-1)));
    }
    public void testSearchOrIndexNodeCacheSizeDefaults() {
        final Settings settings = Settings.builder()
            .putList(
                NodeRoleSettings.NODE_ROLES_SETTING.getKey(),
                randomFrom(DiscoveryNodeRole.SEARCH_ROLE, DiscoveryNodeRole.INDEX_ROLE).roleName()
            )
            .build();
        RelativeByteSizeValue relativeCacheSize = SharedBlobCacheService.SHARED_CACHE_SIZE_SETTING.get(settings);
        assertThat(relativeCacheSize.isAbsolute(), is(false));
        assertThat(relativeCacheSize.isNonZeroSize(), is(true));
        assertThat(relativeCacheSize.calculateValue(ByteSizeValue.ofBytes(10000), null), equalTo(ByteSizeValue.ofBytes(9000)));
        assertThat(SharedBlobCacheService.SHARED_CACHE_SIZE_MAX_HEADROOM_SETTING.get(settings), equalTo(ByteSizeValue.ofGb(100)));
    }
    public void testMaxHeadroomRejectedForAbsoluteCacheSize() {
        String cacheSize = ByteSizeValue.ofBytes(size(500)).getStringRep();
        final Settings settings = Settings.builder()
            .put(SharedBlobCacheService.SHARED_CACHE_SIZE_SETTING.getKey(), cacheSize)
            .put(SharedBlobCacheService.SHARED_CACHE_SIZE_MAX_HEADROOM_SETTING.getKey(), ByteSizeValue.ofBytes(size(100)).getStringRep())
            .putList(NodeRoleSettings.NODE_ROLES_SETTING.getKey(), DiscoveryNodeRole.DATA_FROZEN_NODE_ROLE.roleName())
            .build();
        final IllegalArgumentException e = expectThrows(
            IllegalArgumentException.class,