Add Backend Service Custom Metrics. #13205

efimki · 2025-02-26T21:36:14Z

Release Note Template for Downstream PRs (will be copied)

compute: added `custom_metrics` field to `backend_service` resource. (beta)

gemini-code-assist

Hello @efimki, I'm Gemini Code Assist¹! I'm currently reviewing this pull request and will post my feedback shortly. In the meantime, here's a summary to help you and other reviewers quickly get up to speed!

Summary of Changes

This pull request introduces the ability to use custom metrics for load balancing in Google Compute Engine's Backend Services. It modifies the BackendService.yaml file to include support for CUSTOM_METRICS as a balancing mode and adds related properties for configuring custom metrics. It also introduces WEIGHTED_ROUND_ROBIN as a locality load balancing policy, which uses custom metrics reported by backends to compute weights for per-endpoint load balancing.

Highlights

Balancing Mode: Adds CUSTOM_METRICS as a valid balancing mode for Backend Services, allowing load balancing based on custom utilization signals.
Custom Metrics Configuration: Introduces a customMetrics property to configure the custom metrics used for load balancing, including the metric name, dry-run mode, and target utilization.
Weighted Round Robin Load Balancing: Adds WEIGHTED_ROUND_ROBIN as a locality load balancing policy, enabling per-endpoint weighted round-robin load balancing based on custom metrics reported by backends.
Backend Service Custom Metrics: Adds a customMetrics property to the Backend service, which is a list of custom metrics used for the WEIGHTED_ROUND_ROBIN locality load balancing policy.

Changelog

mmv1/products/compute/BackendService.yaml
- Added CUSTOM_METRICS to the list of valid values for the balancingMode property.
- Added a customMetrics property to configure custom metrics for the CUSTOM_METRICS balancing mode, including name, dryRun, and maxUtilization.
- Added WEIGHTED_ROUND_ROBIN to the list of valid values for the localityLbPolicy property.
- Added a customMetrics property to configure custom metrics for the WEIGHTED_ROUND_ROBIN locality load balancing policy, including name and dryRun.

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A backend's plight, with metrics untold,
Load balancing's dance, both new and old.
Custom signals rise, a weighted decree,
Routing traffic with metrics to see.

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gemini-code-assist

Code Review

This pull request introduces custom metrics for backend services, enhancing the flexibility and control over load balancing configurations. The addition of 'CUSTOM_METRICS' as a balancing mode and the associated properties are well-structured. However, some descriptions could be improved for clarity.

Summary of Findings

Description Clarity: The descriptions for 'customMetrics' and its nested properties could benefit from more clarity, especially regarding the purpose and usage of the metrics.
Dry Run Functionality: The description for the 'dryRun' field could be more explicit about its behavior and implications for load balancing.

Assessment

The pull request introduces custom metrics for backend services, which is a valuable addition. The code changes seem well-structured, but there are a few points that need attention before merging. I recommend addressing the comments provided, particularly regarding the descriptions and potential clarification of the 'dryRun' functionality. Once these issues are resolved, the pull request should be in good shape for merging. As always, ensure that others review and approve this code before merging.

modular-magician · 2025-02-26T21:48:29Z

Hi there, I'm the Modular magician. I've detected the following information about your changes:

Diff report

Your PR generated some diffs in downstreams - here they are.

google provider: Diff ( 3 files changed, 313 insertions(+), 10 deletions(-))
google-beta provider: Diff ( 3 files changed, 313 insertions(+), 10 deletions(-))
terraform-google-conversion: Diff ( 1 file changed, 98 insertions(+))

Missing test report

Your PR includes resource fields which are not covered by any test.

Resource: google_compute_backend_service (182 total tests)
Please add an acceptance test which includes these fields. The test should include the following:

resource "google_compute_backend_service" "primary" {
  backend {
    custom_metrics {
      dry_run         = # value needed
      max_utilization = # value needed
      name            = # value needed
    }
  }
  custom_metrics {
    dry_run = # value needed
    name    = # value needed
  }
}

modular-magician · 2025-02-26T22:10:06Z

Tests analytics

Total tests: 1120
Passed tests: 1043
Skipped tests: 77
Affected tests: 0

Click here to see the affected service packages

compute

🟢 All tests passed!

View the build log

Signed-off-by: Misha Efimov <[email protected]>

modular-magician · 2025-02-26T22:23:03Z

Hi there, I'm the Modular magician. I've detected the following information about your changes:

Diff report

Your PR generated some diffs in downstreams - here they are.

google provider: Diff ( 3 files changed, 356 insertions(+), 10 deletions(-))
google-beta provider: Diff ( 4 files changed, 419 insertions(+), 10 deletions(-))
terraform-google-conversion: Diff ( 1 file changed, 98 insertions(+))

Missing test report

Your PR includes resource fields which are not covered by any test.

Resource: google_compute_backend_service (183 total tests)
Please add an acceptance test which includes these fields. The test should include the following:

resource "google_compute_backend_service" "primary" {
  backend {
    custom_metrics {
      max_utilization = # value needed
    }
  }
}

Signed-off-by: Misha Efimov <[email protected]>

modular-magician · 2025-02-26T22:42:33Z

Tests analytics

Total tests: 1121
Passed tests: 1043
Skipped tests: 77
Affected tests: 1

Click here to see the affected service packages

compute

Action taken

Found 1 affected test(s) by replaying old test recordings. Starting RECORDING based on the most recent commit. Click here to see the affected tests

TestAccComputeBackendService_backendServiceCustomMetricsExample

Get to know how VCR tests work

modular-magician · 2025-02-26T22:43:13Z

🔴 Tests failed during RECORDING mode:
TestAccComputeBackendService_backendServiceCustomMetricsExample [Error message] [Debug log]

🔴 Errors occurred during RECORDING mode. Please fix them to complete your PR.

View the build log or the debug log for each test

modular-magician · 2025-02-26T22:44:32Z

Hi there, I'm the Modular magician. I've detected the following information about your changes:

Diff report

Your PR generated some diffs in downstreams - here they are.

google provider: Diff ( 3 files changed, 354 insertions(+), 10 deletions(-))
google-beta provider: Diff ( 4 files changed, 415 insertions(+), 10 deletions(-))
terraform-google-conversion: Diff ( 1 file changed, 98 insertions(+))

Signed-off-by: Misha Efimov <[email protected]>

modular-magician · 2025-02-26T23:06:04Z

Tests analytics

Total tests: 1121
Passed tests: 1043
Skipped tests: 77
Affected tests: 1

Click here to see the affected service packages

compute

Action taken

Found 1 affected test(s) by replaying old test recordings. Starting RECORDING based on the most recent commit. Click here to see the affected tests

TestAccComputeBackendService_backendServiceCustomMetricsExample

Get to know how VCR tests work

modular-magician · 2025-02-26T23:06:18Z

🔴 Tests failed during RECORDING mode:
TestAccComputeBackendService_backendServiceCustomMetricsExample [Error message] [Debug log]

🔴 Errors occurred during RECORDING mode. Please fix them to complete your PR.

View the build log or the debug log for each test

Signed-off-by: Misha Efimov <[email protected]>

modular-magician · 2025-02-26T23:17:39Z

Hi there, I'm the Modular magician. I've detected the following information about your changes:

Diff report

Your PR generated some diffs in downstreams - here they are.

google provider: Diff ( 3 files changed, 355 insertions(+), 10 deletions(-))
google-beta provider: Diff ( 4 files changed, 417 insertions(+), 10 deletions(-))
terraform-google-conversion: Diff ( 1 file changed, 98 insertions(+))

modular-magician · 2025-02-26T23:28:19Z

Hi there, I'm the Modular magician. I've detected the following information about your changes:

Diff report

Your PR generated some diffs in downstreams - here they are.

google provider: Diff ( 3 files changed, 362 insertions(+), 10 deletions(-))
google-beta provider: Diff ( 4 files changed, 431 insertions(+), 10 deletions(-))
terraform-google-conversion: Diff ( 1 file changed, 98 insertions(+))

modular-magician · 2025-02-26T23:37:25Z

Tests analytics

Total tests: 1121
Passed tests: 1043
Skipped tests: 77
Affected tests: 1

Click here to see the affected service packages

compute

Action taken

Found 1 affected test(s) by replaying old test recordings. Starting RECORDING based on the most recent commit. Click here to see the affected tests

TestAccComputeBackendService_backendServiceCustomMetricsExample

Get to know how VCR tests work

modular-magician · 2025-02-26T23:37:38Z

🔴 Tests failed during RECORDING mode:
TestAccComputeBackendService_backendServiceCustomMetricsExample [Error message] [Debug log]

🔴 Errors occurred during RECORDING mode. Please fix them to complete your PR.

View the build log or the debug log for each test

modular-magician · 2025-02-26T23:47:53Z

Tests analytics

Total tests: 1121
Passed tests: 1043
Skipped tests: 77
Affected tests: 1

Click here to see the affected service packages

compute

Action taken

Found 1 affected test(s) by replaying old test recordings. Starting RECORDING based on the most recent commit. Click here to see the affected tests

TestAccComputeBackendService_backendServiceCustomMetricsExample

Get to know how VCR tests work

modular-magician · 2025-02-26T23:48:07Z

🔴 Tests failed during RECORDING mode:
TestAccComputeBackendService_backendServiceCustomMetricsExample [Error message] [Debug log]

🔴 Errors occurred during RECORDING mode. Please fix them to complete your PR.

View the build log or the debug log for each test

Signed-off-by: Misha Efimov <[email protected]>

modular-magician · 2025-02-27T00:50:44Z

Hi there, I'm the Modular magician. I've detected the following information about your changes:

Diff report

Your PR generated some diffs in downstreams - here they are.

google provider: Diff ( 3 files changed, 359 insertions(+), 10 deletions(-))
google-beta provider: Diff ( 4 files changed, 425 insertions(+), 10 deletions(-))
terraform-google-conversion: Diff ( 1 file changed, 98 insertions(+))

modular-magician · 2025-02-27T01:12:00Z

Tests analytics

Total tests: 1121
Passed tests: 1043
Skipped tests: 77
Affected tests: 1

Click here to see the affected service packages

compute

Action taken

Found 1 affected test(s) by replaying old test recordings. Starting RECORDING based on the most recent commit. Click here to see the affected tests

TestAccComputeBackendService_backendServiceCustomMetricsExample

Get to know how VCR tests work

modular-magician · 2025-02-27T01:12:16Z

🔴 Tests failed during RECORDING mode:
TestAccComputeBackendService_backendServiceCustomMetricsExample [Error message] [Debug log]

🔴 Errors occurred during RECORDING mode. Please fix them to complete your PR.

View the build log or the debug log for each test

Signed-off-by: Misha Efimov <[email protected]>

modular-magician · 2025-02-27T13:19:14Z

Hi there, I'm the Modular magician. I've detected the following information about your changes:

Diff report

Your PR generated some diffs in downstreams - here they are.

google provider: Diff ( 3 files changed, 362 insertions(+), 10 deletions(-))
google-beta provider: Diff ( 4 files changed, 431 insertions(+), 10 deletions(-))
terraform-google-conversion: Diff ( 1 file changed, 98 insertions(+))

modular-magician · 2025-02-27T13:39:28Z

Tests analytics

Total tests: 1121
Passed tests: 1043
Skipped tests: 77
Affected tests: 1

Click here to see the affected service packages

compute

Action taken

Found 1 affected test(s) by replaying old test recordings. Starting RECORDING based on the most recent commit. Click here to see the affected tests

TestAccComputeBackendService_backendServiceCustomMetricsExample

Get to know how VCR tests work

modular-magician · 2025-02-27T13:39:43Z

🔴 Tests failed during RECORDING mode:
TestAccComputeBackendService_backendServiceCustomMetricsExample [Error message] [Debug log]

🔴 Errors occurred during RECORDING mode. Please fix them to complete your PR.

View the build log or the debug log for each test

Signed-off-by: Misha Efimov <[email protected]>

modular-magician · 2025-02-27T15:06:49Z

Hi there, I'm the Modular magician. I've detected the following information about your changes:

Diff report

Your PR generated some diffs in downstreams - here they are.

google provider: Diff ( 3 files changed, 378 insertions(+), 10 deletions(-))
google-beta provider: Diff ( 4 files changed, 463 insertions(+), 10 deletions(-))
terraform-google-conversion: Diff ( 1 file changed, 98 insertions(+))

modular-magician · 2025-02-27T15:26:46Z

Tests analytics

Total tests: 1121
Passed tests: 1043
Skipped tests: 77
Affected tests: 1

Click here to see the affected service packages

compute

Action taken

Found 1 affected test(s) by replaying old test recordings. Starting RECORDING based on the most recent commit. Click here to see the affected tests

TestAccComputeBackendService_backendServiceCustomMetricsExample

Get to know how VCR tests work

modular-magician · 2025-02-27T15:31:31Z

🟢 Tests passed during RECORDING mode:
TestAccComputeBackendService_backendServiceCustomMetricsExample [Debug log]

🟢 No issues found for passed tests after REPLAYING rerun.

🟢 All tests passed!

View the build log or the debug log for each test

efimki · 2025-02-27T15:41:51Z

/retest

Signed-off-by: Misha Efimov <[email protected]>

modular-magician · 2025-02-27T17:54:27Z

Hi there, I'm the Modular magician. I've detected the following information about your changes:

Diff report

Your PR generated some diffs in downstreams - here they are.

google provider: Diff ( 6 files changed, 749 insertions(+), 16 deletions(-))
google-beta provider: Diff ( 8 files changed, 916 insertions(+), 16 deletions(-))
terraform-google-conversion: Diff ( 2 files changed, 196 insertions(+))

modular-magician · 2025-02-27T18:00:53Z

Hi there, I'm the Modular magician. I've detected the following information about your changes:

Diff report

Your PR generated some diffs in downstreams - here they are.

google provider: Diff ( 6 files changed, 749 insertions(+), 16 deletions(-))
google-beta provider: Diff ( 8 files changed, 916 insertions(+), 16 deletions(-))
terraform-google-conversion: Diff ( 2 files changed, 196 insertions(+))

modular-magician · 2025-02-27T18:14:57Z

Tests analytics

Total tests: 1123
Passed tests: 1045
Skipped tests: 77
Affected tests: 1

Click here to see the affected service packages

compute

Action taken

Found 1 affected test(s) by replaying old test recordings. Starting RECORDING based on the most recent commit. Click here to see the affected tests

TestAccComputeRegionBackendService_regionBackendServiceIlbCustomMetricsExample

Get to know how VCR tests work

modular-magician · 2025-02-27T18:18:52Z

🟢 Tests passed during RECORDING mode:
TestAccComputeRegionBackendService_regionBackendServiceIlbCustomMetricsExample [Debug log]

🟢 No issues found for passed tests after REPLAYING rerun.

🟢 All tests passed!

View the build log or the debug log for each test

modular-magician · 2025-02-27T18:21:05Z

Tests analytics

Total tests: 1125
Passed tests: 1045
Skipped tests: 79
Affected tests: 1

Click here to see the affected service packages

compute

Action taken

Found 1 affected test(s) by replaying old test recordings. Starting RECORDING based on the most recent commit. Click here to see the affected tests

TestAccComputeRegionBackendService_regionBackendServiceIlbCustomMetricsExample

Get to know how VCR tests work

modular-magician · 2025-02-27T18:24:49Z

🟢 Tests passed during RECORDING mode:
TestAccComputeRegionBackendService_regionBackendServiceIlbCustomMetricsExample [Debug log]

🟢 No issues found for passed tests after REPLAYING rerun.

🟢 All tests passed!

View the build log or the debug log for each test

github-actions · 2025-02-28T17:14:10Z

Hello! I am a robot. Tests will require approval from a repository maintainer to run.

@slevenick, a repository maintainer, has been assigned to review your changes. If you have not received review feedback within 2 business days, please leave a comment on this PR asking them to take a look.

You can help make sure that review is quick by doing a self-review and by running impacted tests locally.

efimki · 2025-02-28T18:09:51Z

/gemini summary

slevenick

Please add an update test for updating some of these fields. Things like:

Adding a custom metric when several already exist
Removing a custom metric from several
Updating dry_run from true -> false. We typically see issues with this type of update, so it would be good to check

slevenick · 2025-02-28T21:36:57Z

mmv1/products/compute/BackendService.yaml

+          type: Array
+          description: |
+            The set of custom metrics that are used for <code>CUSTOM_METRICS</code> BalancingMode.
+          is_set: false


This should be the default, so it's not needed

slevenick · 2025-02-28T21:37:33Z

mmv1/products/compute/BackendService.yaml

@@ -960,6 +1010,31 @@ properties:
              description: |
                An optional, arbitrary JSON object with configuration data, understood
                by a locally installed custom policy implementation.
+  - name: 'customMetrics'


Does this not need maxUtilization?

slevenick · 2025-02-28T21:38:10Z

mmv1/templates/terraform/examples/region_backend_service_ilb_custom_metrics.tf.tmpl

+    }
+    custom_metrics {
+      name    = "orca.named_metrics.foo"
+      max_utilization = 0.9


Can you not set this value in one of these tests?

Add Backend Service Custom Metrics.

b4ae5ff

gemini-code-assist bot reviewed Feb 26, 2025

View reviewed changes

modular-magician added the service/compute-l7-load-balancer label Feb 26, 2025

Add an example.

d03dbd5

Signed-off-by: Misha Efimov <[email protected]>

Add max_utilization to an example.

267a5a2

Signed-off-by: Misha Efimov <[email protected]>

Set load_balancing_scheme = "EXTERNAL_MANAGED"

a64accf

Signed-off-by: Misha Efimov <[email protected]>

Use hybrid NEG.

6e2310a

Signed-off-by: Misha Efimov <[email protected]>

Remove provider=google-beta

1d8b4d6

Signed-off-by: Misha Efimov <[email protected]>

Add back provider = google-beta

c822f4a

Signed-off-by: Misha Efimov <[email protected]>

Make tests work locally.

d4d289c

Signed-off-by: Misha Efimov <[email protected]>

efimki added 2 commits February 27, 2025 12:42

Add Custom Metrics to Region Backend Service.

e0cfbae

Signed-off-by: Misha Efimov <[email protected]>

Fix trailing whitespace.

0c9fbe4

Signed-off-by: Misha Efimov <[email protected]>

efimki marked this pull request as ready for review February 28, 2025 17:13

github-actions bot requested a review from slevenick February 28, 2025 17:14

pawelJas approved these changes Feb 28, 2025

View reviewed changes

slevenick requested changes Feb 28, 2025

View reviewed changes

Add Backend Service Custom Metrics. #13205

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Add Backend Service Custom Metrics. #13205

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efimki commented Feb 26, 2025 • edited Loading

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Summary of Changes

Highlights

Changelog

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Code Review

Summary of Findings

Assessment

modular-magician commented Feb 26, 2025

Diff report

Missing test report

modular-magician commented Feb 26, 2025

Tests analytics

modular-magician commented Feb 26, 2025

Diff report

Missing test report

modular-magician commented Feb 26, 2025

Tests analytics

Action taken

modular-magician commented Feb 26, 2025

modular-magician commented Feb 26, 2025

Diff report

modular-magician commented Feb 26, 2025

Tests analytics

Action taken

modular-magician commented Feb 26, 2025

modular-magician commented Feb 26, 2025

Diff report

modular-magician commented Feb 26, 2025

Diff report

modular-magician commented Feb 26, 2025

Tests analytics

Action taken

modular-magician commented Feb 26, 2025

modular-magician commented Feb 26, 2025

Tests analytics

Action taken

modular-magician commented Feb 26, 2025

modular-magician commented Feb 27, 2025

Diff report

modular-magician commented Feb 27, 2025

Tests analytics

Action taken

modular-magician commented Feb 27, 2025

modular-magician commented Feb 27, 2025

Diff report

modular-magician commented Feb 27, 2025

Tests analytics

Action taken

modular-magician commented Feb 27, 2025

modular-magician commented Feb 27, 2025

Diff report

modular-magician commented Feb 27, 2025

Tests analytics

Action taken

modular-magician commented Feb 27, 2025

efimki commented Feb 27, 2025

modular-magician commented Feb 27, 2025

Diff report

modular-magician commented Feb 27, 2025

Diff report

modular-magician commented Feb 27, 2025

Tests analytics

Action taken

modular-magician commented Feb 27, 2025

modular-magician commented Feb 27, 2025

Tests analytics

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modular-magician commented Feb 27, 2025

github-actions bot commented Feb 28, 2025

efimki commented Feb 28, 2025

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efimki commented Feb 26, 2025 •

edited

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