Split sliding_window_size and max_histogram_buckets for the individual LCPP subprojects

Currently, LCPP projects share the following fields.

- sliding_window_size
- max_histogram_buckets

Sharing these fields prevents us from specifying different values for
the individual subprojects of LCPP.

Bug: 40063266
Change-Id: I92d88f17a48092f9f9200cdb1a72150509367293
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/6389125
Reviewed-by: Kouhei Ueno <kouhei@chromium.org>
Reviewed-by: Shunya Shishido <sisidovski@chromium.org>
Reviewed-by: Yoichi Osato <yoichio@chromium.org>
Commit-Queue: Minoru Chikamune <chikamune@chromium.org>
Cr-Commit-Position: refs/heads/main@{#1437957}

chrome/browser/predictors/lcp_critical_path_predictor/lcp_critical_path_predictor_util.cc

@@ -1000,27 +1000,29 @@ LcppDataInputs::~LcppDataInputs() = default;
 bool UpdateLcppStatWithLcppDataInputs(const LcppDataInputs& inputs,
                                       LcppStat& stat) {
   bool data_updated = false;
-  int sliding_window_size =
-      blink::features::kLCPCriticalPathPredictorHistogramSlidingWindowSize
-          .Get();
-  int max_histogram_buckets =
-      blink::features::kLCPCriticalPathPredictorMaxHistogramBuckets.Get();
   data_updated |= RecordLcpElementLocatorHistogram(
-      sliding_window_size, max_histogram_buckets, inputs.lcp_element_locator,
-      stat);
+      blink::features::kLCPCriticalPathPredictorSlidingWindowSize.Get(),
+      blink::features::kLCPCriticalPathPredictorMaxHistogramBuckets.Get(),
+      inputs.lcp_element_locator, stat);
   data_updated |= RecordLcpInfluencerScriptUrlsHistogram(
-      sliding_window_size, max_histogram_buckets, inputs.lcp_influencer_scripts,
-      stat);
+      blink::features::kLCPScriptObserverSlidingWindowSize.Get(),
+      blink::features::kLCPScriptObserverMaxHistogramBuckets.Get(),
+      inputs.lcp_influencer_scripts, stat);
   data_updated |= RecordFetchedFontUrlsHistogram(
-      sliding_window_size, max_histogram_buckets, inputs.font_urls, stat);
+      blink::features::kLCPPFontURLPredictorSlidingWindowSize.Get(),
+      blink::features::kLCPPFontURLPredictorMaxHistogramBuckets.Get(),
+      inputs.font_urls, stat);
   data_updated |= RecordFetchedSubresourceUrlsHistogram(
-      sliding_window_size, max_histogram_buckets, inputs.subresource_urls,
-      stat);
+      blink::features::kHttpDiskCachePrewarmingSlidingWindowSize.Get(),
+      blink::features::kHttpDiskCachePrewarmingMaxHistogramBuckets.Get(),
+      inputs.subresource_urls, stat);
   data_updated |= RecordPreconnectOriginsHistogram(
-      sliding_window_size, max_histogram_buckets, inputs.preconnect_origins,
-      stat);
+      blink::features::kLCPPAutoPreconnectSlidingWindowSize.Get(),
+      blink::features::kLCPPAutoPreconnectMaxHistogramBuckets.Get(),
+      inputs.preconnect_origins, stat);
   data_updated |= RecordUnusedPreloadUrlsHistogram(
-      sliding_window_size, max_histogram_buckets,
+      blink::features::kLCPPDeferUnusedPreloadSlidingWindowSize.Get(),
+      blink::features::kLCPPDeferUnusedPreloadMaxHistogramBuckets.Get(),
       inputs.unused_preload_resources, stat);
   base::UmaHistogramCounts10000("Blink.LCPP.ReportedFontCount",
                                 base::checked_cast<int>(inputs.font_url_count));

chrome/browser/predictors/lcp_critical_path_predictor/lcp_critical_path_predictor_util_unittest.cc

@@ -1466,15 +1466,49 @@ class LcppDataMapFeatures
   LcppDataMapFeatures() {
     scoped_feature_list_.InitWithFeatures(GetParam(),
                                           /*disabled_features=*/{});
+    constexpr char kSlidingWindowSize[] = "5";
+    constexpr char kMaxHistogramBuckets[] = "2";
     scoped_feature_list_for_sliding_window_and_buckets_
         .InitWithFeaturesAndParameters(
-            {{blink::features::kLCPCriticalPathPredictor,
-              {{blink::features::
-                    kLCPCriticalPathPredictorHistogramSlidingWindowSize.name,
-                "5"},
-               {blink::features::kLCPCriticalPathPredictorMaxHistogramBuckets
-                    .name,
-                "2"}}}},
+            {
+                {blink::features::kLCPCriticalPathPredictor,
+                 {{blink::features::kLCPCriticalPathPredictorSlidingWindowSize
+                       .name,
+                   kSlidingWindowSize},
+                  {blink::features::kLCPCriticalPathPredictorMaxHistogramBuckets
+                       .name,
+                   kMaxHistogramBuckets}}},
+                {blink::features::kLCPScriptObserver,
+                 {{blink::features::kLCPScriptObserverSlidingWindowSize.name,
+                   kSlidingWindowSize},
+                  {blink::features::kLCPScriptObserverMaxHistogramBuckets.name,
+                   kMaxHistogramBuckets}}},
+                {blink::features::kLCPPFontURLPredictor,
+                 {{blink::features::kLCPPFontURLPredictorSlidingWindowSize.name,
+                   kSlidingWindowSize},
+                  {blink::features::kLCPPFontURLPredictorMaxHistogramBuckets
+                       .name,
+                   kMaxHistogramBuckets}}},
+                {blink::features::kHttpDiskCachePrewarming,
+                 {{blink::features::kHttpDiskCachePrewarmingSlidingWindowSize
+                       .name,
+                   kSlidingWindowSize},
+                  {blink::features::kHttpDiskCachePrewarmingMaxHistogramBuckets
+                       .name,
+                   kMaxHistogramBuckets}}},
+                {blink::features::kLCPPAutoPreconnectLcpOrigin,
+                 {{blink::features::kLCPPAutoPreconnectSlidingWindowSize.name,
+                   kSlidingWindowSize},
+                  {blink::features::kLCPPAutoPreconnectMaxHistogramBuckets.name,
+                   kMaxHistogramBuckets}}},
+                {blink::features::kLCPPDeferUnusedPreload,
+                 {{blink::features::kLCPPDeferUnusedPreloadSlidingWindowSize
+                       .name,
+                   kSlidingWindowSize},
+                  {blink::features::kLCPPDeferUnusedPreloadMaxHistogramBuckets
+                       .name,
+                   kMaxHistogramBuckets}}},
+            },
             {});
   }
 

testing/variations/fieldtrial_testing_config.json

@@ -13605,12 +13605,12 @@
                         "lcpp_adjust_image_load_priority_override_first_n_boost": "true",
                         "lcpp_enable_image_load_priority_for_htmlimageelement": "false",
                         "lcpp_enable_perf_improvements": "true",
-                        "lcpp_histogram_sliding_window_size": "1000",
                         "lcpp_image_load_priority": "medium",
                         "lcpp_max_element_locator_length": "1024",
                         "lcpp_max_histogram_buckets": "10",
                         "lcpp_max_hosts_to_track": "100",
-                        "lcpp_recorded_lcp_element_types": "image_only"
+                        "lcpp_recorded_lcp_element_types": "image_only",
+                        "lcpp_sliding_window_size": "1000"
                     },
                     "enable_features": [
                         "LCPCriticalPathPredictor"

third_party/blink/common/features.cc

@@ -1318,9 +1318,9 @@ BASE_FEATURE_PARAM(int,
                    100);
 
 BASE_FEATURE_PARAM(int,
-                   kLCPCriticalPathPredictorHistogramSlidingWindowSize,
+                   kLCPCriticalPathPredictorSlidingWindowSize,
                    &kLCPCriticalPathPredictor,
-                   "lcpp_histogram_sliding_window_size",
+                   "lcpp_sliding_window_size",
                    1000);
 
 BASE_FEATURE_PARAM(int,
@@ -1365,6 +1365,18 @@ BASE_FEATURE_PARAM(bool,
                    "lcpscriptobserver_adjust_image_load_priority",
                    false);
 
+BASE_FEATURE_PARAM(int,
+                   kLCPScriptObserverSlidingWindowSize,
+                   &kLCPScriptObserver,
+                   "lcpscriptobserver_sliding_window_size",
+                   1000);
+
+BASE_FEATURE_PARAM(int,
+                   kLCPScriptObserverMaxHistogramBuckets,
+                   &kLCPScriptObserver,
+                   "lcpscriptobserver_max_histogram_buckets",
+                   10);
+
 BASE_FEATURE(kLCPTimingPredictorPrerender2,
              "LCPTimingPredictorPrerender2",
              base::FEATURE_DISABLED_BY_DEFAULT);
@@ -1385,6 +1397,18 @@ BASE_FEATURE_PARAM(int,
                    "lcpp_preconnect_max_origins",
                    2);
 
+BASE_FEATURE_PARAM(int,
+                   kLCPPAutoPreconnectSlidingWindowSize,
+                   &kLCPPAutoPreconnectLcpOrigin,
+                   "lcpp_preconnect_sliding_window_size",
+                   1000);
+
+BASE_FEATURE_PARAM(int,
+                   kLCPPAutoPreconnectMaxHistogramBuckets,
+                   &kLCPPAutoPreconnectLcpOrigin,
+                   "lcpp_preconnect_max_histogram_buckets",
+                   10);
+
 BASE_FEATURE(kLCPPDeferUnusedPreload,
              "LCPPDeferUnusedPreload",
              base::FEATURE_DISABLED_BY_DEFAULT);
@@ -1442,6 +1466,18 @@ BASE_FEATURE_ENUM_PARAM(LcppDeferUnusedPreloadTiming,
                         LcppDeferUnusedPreloadTiming::kPostTask,
                         &lcpp_defer_unused_preload_timing);
 
+BASE_FEATURE_PARAM(int,
+                   kLCPPDeferUnusedPreloadSlidingWindowSize,
+                   &kLCPPDeferUnusedPreload,
+                   "lcpp_unused_preload_sliding_window_size",
+                   1000);
+
+BASE_FEATURE_PARAM(int,
+                   kLCPPDeferUnusedPreloadMaxHistogramBuckets,
+                   &kLCPPDeferUnusedPreload,
+                   "lcpp_unused_preload_max_histogram_buckets",
+                   10);
+
 BASE_FEATURE(kLCPPFontURLPredictor,
              "LCPPFontURLPredictor",
              base::FEATURE_DISABLED_BY_DEFAULT);
@@ -1492,6 +1528,18 @@ BASE_FEATURE_PARAM(bool,
                    "lcpp_cross_site_font_prediction_allowed",
                    false);
 
+BASE_FEATURE_PARAM(int,
+                   kLCPPFontURLPredictorSlidingWindowSize,
+                   &kLCPPFontURLPredictor,
+                   "lcpp_font_sliding_window_size",
+                   1000);
+
+BASE_FEATURE_PARAM(int,
+                   kLCPPFontURLPredictorMaxHistogramBuckets,
+                   &kLCPPFontURLPredictor,
+                   "lcpp_font_max_histogram_buckets",
+                   10);
+
 BASE_FEATURE(kLCPPInitiatorOrigin,
              "LCPPInitiatorOrigin",
              base::FEATURE_ENABLED_BY_DEFAULT);
@@ -1633,6 +1681,18 @@ BASE_FEATURE_PARAM(bool,
                    "http_disk_cache_prewarming_skip_during_browser_startup",
                    true);
 
+BASE_FEATURE_PARAM(int,
+                   kHttpDiskCachePrewarmingSlidingWindowSize,
+                   &kHttpDiskCachePrewarming,
+                   "http_disk_cache_prewarming_sliding_window_size",
+                   1000);
+
+BASE_FEATURE_PARAM(int,
+                   kHttpDiskCachePrewarmingMaxHistogramBuckets,
+                   &kHttpDiskCachePrewarming,
+                   "http_disk_cache_prewarming_max_histogram_buckets",
+                   10);
+
 BASE_FEATURE(kLegacyParsingOfXContentTypeOptions,
              "LegacyParsingOfXContentTypeOptions",
              base::FEATURE_DISABLED_BY_DEFAULT);

third_party/blink/public/common/features.h

@@ -836,11 +836,10 @@ BLINK_COMMON_EXPORT BASE_DECLARE_FEATURE_PARAM(
     int,
     kLCPCriticalPathPredictorMaxHostsToTrack);
 
-// The virtual sliding window size for LCP critical path predictor (LCPP)
-// histogram.
+// The virtual sliding window size for LCP critical path predictor (LCPP).
 BLINK_COMMON_EXPORT BASE_DECLARE_FEATURE_PARAM(
     int,
-    kLCPCriticalPathPredictorHistogramSlidingWindowSize);
+    kLCPCriticalPathPredictorSlidingWindowSize);
 
 // The max histogram bucket count that can be stored in the LCP critical path
 // predictor (LCPP) database.
@@ -876,6 +875,17 @@ BLINK_COMMON_EXPORT BASE_DECLARE_FEATURE_PARAM(
     bool,
     kLCPScriptObserverAdjustImageLoadPriority);
 
+// The virtual sliding window size for kLCPScriptObserver.
+BLINK_COMMON_EXPORT BASE_DECLARE_FEATURE_PARAM(
+    int,
+    kLCPScriptObserverSlidingWindowSize);
+
+// The max histogram bucket count that can be stored in the LCP critical path
+// predictor (LCPP) database for kLCPScriptObserver.
+BLINK_COMMON_EXPORT BASE_DECLARE_FEATURE_PARAM(
+    int,
+    kLCPScriptObserverMaxHistogramBuckets);
+
 // If enabled, Prerender2 by Speculation Rules API is delayed until
 // LCP is finished.
 BLINK_COMMON_EXPORT BASE_DECLARE_FEATURE(kLCPTimingPredictorPrerender2);
@@ -894,6 +904,17 @@ BLINK_COMMON_EXPORT BASE_DECLARE_FEATURE_PARAM(
     int,
     kkLCPPAutoPreconnectMaxPreconnectOriginsCount);
 
+// The virtual sliding window size for kLCPPAutoPreconnectLcpOrigin.
+BLINK_COMMON_EXPORT BASE_DECLARE_FEATURE_PARAM(
+    int,
+    kLCPPAutoPreconnectSlidingWindowSize);
+
+// The max histogram bucket count that can be stored in the LCP critical path
+// predictor (LCPP) database for kLCPPAutoPreconnectLcpOrigin.
+BLINK_COMMON_EXPORT BASE_DECLARE_FEATURE_PARAM(
+    int,
+    kLCPPAutoPreconnectMaxHistogramBuckets);
+
 // If enabled, unused preload requests are deferred to the timing on LCP.
 BLINK_COMMON_EXPORT BASE_DECLARE_FEATURE(kLCPPDeferUnusedPreload);
 
@@ -947,6 +968,17 @@ enum class LcppDeferUnusedPreloadTiming {
 BLINK_COMMON_EXPORT BASE_DECLARE_FEATURE_PARAM(LcppDeferUnusedPreloadTiming,
                                                kLcppDeferUnusedPreloadTiming);
 
+// The virtual sliding window size for kLCPPDeferUnusedPreload.
+BLINK_COMMON_EXPORT BASE_DECLARE_FEATURE_PARAM(
+    int,
+    kLCPPDeferUnusedPreloadSlidingWindowSize);
+
+// The max histogram bucket count that can be stored in the LCP critical path
+// predictor (LCPP) database for kLCPPDeferUnusedPreload.
+BLINK_COMMON_EXPORT BASE_DECLARE_FEATURE_PARAM(
+    int,
+    kLCPPDeferUnusedPreloadMaxHistogramBuckets);
+
 // If enabled, fetched font URLs are observed to predict font usage in the
 // future navigation.
 BLINK_COMMON_EXPORT BASE_DECLARE_FEATURE(kLCPPFontURLPredictor);
@@ -996,6 +1028,17 @@ BLINK_COMMON_EXPORT BASE_DECLARE_FEATURE_PARAM(
     bool,
     kLCPPCrossSiteFontPredictionAllowed);
 
+// The virtual sliding window size for kLCPPFontURLPredictor.
+BLINK_COMMON_EXPORT BASE_DECLARE_FEATURE_PARAM(
+    int,
+    kLCPPFontURLPredictorSlidingWindowSize);
+
+// The max histogram bucket count that can be stored in the LCP critical path
+// predictor (LCPP) database for kLCPPFontURLPredictor.
+BLINK_COMMON_EXPORT BASE_DECLARE_FEATURE_PARAM(
+    int,
+    kLCPPFontURLPredictorMaxHistogramBuckets);
+
 // If enabled, LCPP learns with a navigation-initiator origin.
 BLINK_COMMON_EXPORT BASE_DECLARE_FEATURE(kLCPPInitiatorOrigin);
 
@@ -1112,6 +1155,17 @@ BLINK_COMMON_EXPORT BASE_DECLARE_FEATURE_PARAM(
     bool,
     kHttpDiskCachePrewarmingSkipDuringBrowserStartup);
 
+// The virtual sliding window size for kLCPScriptObserver.
+BLINK_COMMON_EXPORT BASE_DECLARE_FEATURE_PARAM(
+    int,
+    kHttpDiskCachePrewarmingSlidingWindowSize);
+
+// The max histogram bucket count that can be stored in the LCP critical path
+// predictor (LCPP) database for kLCPScriptObserver.
+BLINK_COMMON_EXPORT BASE_DECLARE_FEATURE_PARAM(
+    int,
+    kHttpDiskCachePrewarmingMaxHistogramBuckets);
+
 // Kill-switch for new parsing behaviour of the X-Content-Type-Options header.
 // (Should be removed after the new behaviour has been launched.)
 BLINK_COMMON_EXPORT BASE_DECLARE_FEATURE(kLegacyParsingOfXContentTypeOptions);