Precache: Optionally rank resources-to-precache globally.

components/precache/core/proto/precache.proto

 // Copyright 2013 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 syntax = "proto2";
 
 package precache;
 
 // Chrome requires this.
 option optimize_for = LITE_RUNTIME;
 
 // Information about a cacheable resource to be precached.
 message PrecacheResource {
   // The URL of the resource. This field must always be present.
   optional string url = 1;
 
   // The tophost this resource corresponds to.
   optional string top_host_name = 2;
+
+  // How important this resource is for the host. It ranges from 0.0 to 1.0.
+  // Higher values mean more important.
+  optional double weight_ratio = 3;
 };
 
 message PrecacheManifestId {
   optional int64 id = 1;
 };
 
 // A manifest of cacheable resources to be precached for a specific host.
 message PrecacheManifest {
   // List of resources that we predict that the user will need if they are
   // likely to fetch the host.
@@ skipping 53 matching lines @@
   // The maximum number of bytes per precache run. While precaching, the total
   // number of bytes used for resources is tallied -- this includes new
   // downloads as well as cached resources. After this limit is reached, no
   // other resources will be downloaded.
   optional uint64 max_bytes_total = 5 [default = 10000000 /* 10 MB */];
 
   // The maximum number of bytes that can be fetched by precache on a single
   // day. After this limit is reached, no more resources will be downloaded,
   // until the quota gets replenished the next day.
   optional uint64 daily_quota_total = 6 [default = 40000000 /* 40 MB */];
+
+  // The number of resources to fetch per precache run. Only the first
+  // |total_resources_count| resource URLs are fetched.
+  optional uint32 total_resources_count = 7 [default = 999999];
+
+  // The minimum visit-adjusted weight for which a resource will be downloaded.
+  optional double min_weight = 8 [default = 0];
+
+  // Whether to sort resources by weight, descending, before fetching. This
+  // affects the fetcher's behavior with respect to max_bytes_total and
+  // total_resources_count.
+  optional bool global_ranking = 9 [default = false];
 };