SimpleCache: read small files all at once.

net/disk_cache/simple/simple_experiment.cc

Index: net/disk_cache/simple/simple_experiment.cc
diff --git a/net/disk_cache/simple/simple_experiment.cc b/net/disk_cache/simple/simple_experiment.cc
index 38ea589322f97df405f9b48bcaa349510847ce52..7b355f479d60c407ef0cef6cd78b510dbfaba5a1 100644
--- a/net/disk_cache/simple/simple_experiment.cc
+++ b/net/disk_cache/simple/simple_experiment.cc
@@ -9,6 +9,7 @@
 
 #include "base/metrics/field_trial.h"
 #include "base/metrics/field_trial_param_associator.h"
+#include "base/metrics/field_trial_params.h"
 #include "base/strings/string_number_conversions.h"
 
 namespace disk_cache {
@@ -17,6 +18,10 @@ const base::Feature kSimpleSizeExperiment = {"SimpleSizeExperiment",
                                              base::FEATURE_DISABLED_BY_DEFAULT};
 const char kSizeMultiplierParam[] = "SizeMultiplier";
 
+const base::Feature kSimpleCachePrefetchExperiment = {
+    "GetSimpleCachePrefetchExperiment", base::FEATURE_DISABLED_BY_DEFAULT};
+const char kSimplePrefetchBytesParam[] = "Bytes";
+
 namespace {
 
 // Returns true if the experiment is found and properly defined.
@@ -61,4 +66,9 @@ SimpleExperiment GetSimpleExperiment(net::CacheType cache_type) {
   return experiment;
 }
 
+int GetSimpleCachePrefetchSize() {
+  return base::GetFieldTrialParamByFeatureAsInt(kSimpleCachePrefetchExperiment,

[pasko, 2017/07/18 14:02:57]

please also add a test that sets the experiment param differently and confirms
that things work on the SSEntry level.

[Maks Orlovich, 2017/07/25 16:06:29]

Done.

+                                                kSimplePrefetchBytesParam, 0);
+}
+
 }  // namespace disk_cache