Skip to content

Flink: Backport: Fix monitor source rate limit for sub-second intervals (#16979) #16992

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Merged
singhpk234 merged 1 commit into from
Jun 28, 2026
+44 −2
Merged

Flink: Backport: Fix monitor source rate limit for sub-second intervals (#16979) #16992

Show file tree
Hide file tree
Changes from all commits
Commits
Show all changes
1 commit
Select commit
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
15 changes: 14 additions & 1 deletion .../v1.20/flink/src/main/java/org/apache/iceberg/flink/maintenance/api/TableMaintenance.java
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -26,6 +26,7 @@
import java.util.UUID;
import javax.annotation.Nullable;
import org.apache.flink.annotation.Internal;
import org.apache.flink.annotation.VisibleForTesting;
import org.apache.flink.api.common.ExecutionConfig;
import org.apache.flink.api.common.eventtime.TimestampAssigner;
import org.apache.flink.api.common.eventtime.TimestampAssignerSupplier;
Expand Down Expand Up @@ -378,7 +379,9 @@ private DataStream<TableChange> changeStream(String tableName, TableLoader loade
// Create a monitor source to provide the TableChange stream
MonitorSource source =
new MonitorSource(
loader, RateLimiterStrategy.perSecond(1.0 / rateLimit.getSeconds()), maxReadBack);
loader,
RateLimiterStrategy.perSecond(monitorRatePerSecond(rateLimit.toMillis())),
maxReadBack);
return setSlotSharingGroup(
env.fromSource(
source,
Expand All @@ -395,6 +398,16 @@ private static String nameFor(MaintenanceTaskBuilder<?> streamBuilder, int taskI
return String.format(Locale.ROOT, "%s [%d]", streamBuilder.maintenanceTaskName(), taskIndex);
}

/**
* Monitor poll rate per rate-limit interval, in checks/second. We compute from millis instead
* of seconds, otherwise sub-second intervals could be truncated to 0, yielding an infinite rate
* which busy-loops the source.
*/
@VisibleForTesting
static double monitorRatePerSecond(long rateLimitMillis) {
return 1000.0 / rateLimitMillis;
}

private <T> SingleOutputStreamOperator<T> setSlotSharingGroup(
SingleOutputStreamOperator<T> operator) {
return slotSharingGroup == null ? operator : operator.slotSharingGroup(slotSharingGroup);
Expand Down
8 changes: 8 additions & 0 deletions ...20/flink/src/test/java/org/apache/iceberg/flink/maintenance/api/TestTableMaintenance.java
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -350,6 +350,14 @@ void testUidAndSlotSharingGroupForMonitorSource() throws IOException {
checkSlotSharingGroupsAreSet(env, SLOT_SHARING_GROUP);
}

@Test
void testMonitorRatePerSecond() {
// Sub-second rate limits must not yield infinite (unthrottled) monitor rates.
assertThat(TableMaintenance.Builder.monitorRatePerSecond(50)).isEqualTo(20.0);
assertThat(TableMaintenance.Builder.monitorRatePerSecond(100)).isEqualTo(10.0);
assertThat(TableMaintenance.Builder.monitorRatePerSecond(60_000)).isEqualTo(1.0 / 60);
}

/**
* Sends the events though the {@link ManualSource} provided, and waits until the given number of
* records are processed.
Expand Down
15 changes: 14 additions & 1 deletion ...k/v2.0/flink/src/main/java/org/apache/iceberg/flink/maintenance/api/TableMaintenance.java
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -26,6 +26,7 @@
import java.util.UUID;
import javax.annotation.Nullable;
import org.apache.flink.annotation.Internal;
import org.apache.flink.annotation.VisibleForTesting;
import org.apache.flink.api.common.ExecutionConfig;
import org.apache.flink.api.common.eventtime.TimestampAssigner;
import org.apache.flink.api.common.eventtime.TimestampAssignerSupplier;
Expand Down Expand Up @@ -378,7 +379,9 @@ private DataStream<TableChange> changeStream(String tableName, TableLoader loade
// Create a monitor source to provide the TableChange stream
MonitorSource source =
new MonitorSource(
loader, RateLimiterStrategy.perSecond(1.0 / rateLimit.getSeconds()), maxReadBack);
loader,
RateLimiterStrategy.perSecond(monitorRatePerSecond(rateLimit.toMillis())),
maxReadBack);
return setSlotSharingGroup(
env.fromSource(
source,
Expand All @@ -395,6 +398,16 @@ private static String nameFor(MaintenanceTaskBuilder<?> streamBuilder, int taskI
return String.format(Locale.ROOT, "%s [%d]", streamBuilder.maintenanceTaskName(), taskIndex);
}

/**
* Monitor poll rate per rate-limit interval, in checks/second. We compute from millis instead
* of seconds, otherwise sub-second intervals could be truncated to 0, yielding an infinite rate
* which busy-loops the source.
*/
@VisibleForTesting
static double monitorRatePerSecond(long rateLimitMillis) {
return 1000.0 / rateLimitMillis;
}

private <T> SingleOutputStreamOperator<T> setSlotSharingGroup(
SingleOutputStreamOperator<T> operator) {
return slotSharingGroup == null ? operator : operator.slotSharingGroup(slotSharingGroup);
Expand Down
8 changes: 8 additions & 0 deletions ....0/flink/src/test/java/org/apache/iceberg/flink/maintenance/api/TestTableMaintenance.java
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -350,6 +350,14 @@ void testUidAndSlotSharingGroupForMonitorSource() throws IOException {
checkSlotSharingGroupsAreSet(env, SLOT_SHARING_GROUP);
}

@Test
void testMonitorRatePerSecond() {
// Sub-second rate limits must not yield infinite (unthrottled) monitor rates.
assertThat(TableMaintenance.Builder.monitorRatePerSecond(50)).isEqualTo(20.0);
assertThat(TableMaintenance.Builder.monitorRatePerSecond(100)).isEqualTo(10.0);
assertThat(TableMaintenance.Builder.monitorRatePerSecond(60_000)).isEqualTo(1.0 / 60);
}

/**
* Sends the events though the {@link ManualSource} provided, and waits until the given number of
* records are processed.
Expand Down