Http cache: fix a bug that prevented the infinite cache simulation from saving

large data sets.

Also, go back to a limit of 200k entries, to monitor things, and increase the
version number to have clean stats after this change.

BUG=147383
TEST=none
Review URL: https://codereview.chromium.org/11415222

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@170548 0039d316-1c4b-4281-b951-d872f2087c98

net/http/infinite_cache.cc

@@ -82,10 +82,10 @@ const size_t kRecordSize = sizeof(Key) + sizeof(Details);
 
 // Some constants related to the database file.
 uint32 kMagicSignature = 0x1f00cace;
-uint32 kCurrentVersion = 0x10001;
+uint32 kCurrentVersion = 0x10002;
 
 // Basic limits for the experiment.
-int kMaxNumEntries = 500 * 1000;
+int kMaxNumEntries = 200 * 1000;
 int kMaxTrackingSize = 40 * 1024 * 1024;
 
 // Settings that control how we generate histograms.
@@ -604,7 +604,7 @@ void InfiniteCache::Worker::LoadData() {
   base::ClosePlatformFile(file);
   if (header_->disabled) {
     UMA_HISTOGRAM_BOOLEAN("InfiniteCache.Full", true);
-    map_.clear();
+    InitializeData();
   }
 }
 
@@ -639,6 +639,7 @@ void InfiniteCache::Worker::InitializeData() {
   header_->magic = kMagicSignature;
   header_->version = kCurrentVersion;
   header_->creation_time = Time::Now().ToInternalValue();
+  map_.clear();
 
   UMA_HISTOGRAM_BOOLEAN("InfiniteCache.Initialize", true);
   init_ = true;
@@ -653,7 +654,7 @@ bool InfiniteCache::Worker::ReadData(PlatformFile file) {
   uint32 hash = adler32(0, Z_NULL, 0);
 
   for (int remaining_records = header_->num_entries; remaining_records;) {
-    int num_records = std::min(header_->num_entries,
+    int num_records = std::min(remaining_records,
                                static_cast<int>(kMaxRecordsToRead));
     size_t num_bytes = num_records * kRecordSize;
     remaining_records -= num_records;
@@ -703,7 +704,7 @@ bool InfiniteCache::Worker::WriteData(PlatformFile file) {
   DCHECK_EQ(header_->num_entries, static_cast<int32>(map_.size()));
   KeyMap::iterator iterator = map_.begin();
   for (int remaining_records = header_->num_entries; remaining_records;) {
-    int num_records = std::min(header_->num_entries,
+    int num_records = std::min(remaining_records,
                                static_cast<int>(kMaxRecordsToRead));
     size_t num_bytes = num_records * kRecordSize;
     remaining_records -= num_records;
@@ -804,6 +805,7 @@ void InfiniteCache::Worker::Add(const Details& details) {
     int entry_size = static_cast<int>(header_->total_size / kMaxNumEntries);
     UMA_HISTOGRAM_COUNTS("InfiniteCache.FinalAvgEntrySize", entry_size);
     header_->disabled = 1;
+    header_->num_entries = 0;
     map_.clear();
   }
 }

net/http/infinite_cache_unittest.cc

@@ -6,6 +6,7 @@
 
 #include "base/file_util.h"
 #include "base/files/scoped_temp_dir.h"
+#include "base/stringprintf.h"
 #include "base/threading/platform_thread.h"
 #include "base/time.h"
 #include "net/base/net_errors.h"
@@ -245,3 +246,31 @@ TEST(InfiniteCache, DeleteBetween) {
   EXPECT_EQ(1, cb.GetResult(cache->QueryItemsForTest(cb.callback())));
 #endif  // OS_ANDROID
 }
+
+#if 0
+// This test is too slow for the bots.
+TEST(InfiniteCache, FillUp) {
+  base::ScopedTempDir dir;
+  ASSERT_TRUE(dir.CreateUniqueTempDir());
+  FilePath path = dir.path().Append(FILE_PATH_LITERAL("infinite"));
+
+  scoped_ptr<InfiniteCache> cache(new InfiniteCache);
+  cache->Init(path);
+  net::TestCompletionCallback cb;
+
+  const int kNumEntries = 25000;
+  for (int i = 0; i < kNumEntries; i++) {
+    std::string url = StringPrintf("http://foo.com/%d/foo.html", i);
+    MockTransaction transaction = kTypicalGET_Transaction;
+    transaction.url = url.c_str();
+    ProcessRequest(transaction, cache.get());
+  }
+
+  EXPECT_EQ(kNumEntries, cb.GetResult(cache->QueryItemsForTest(cb.callback())));
+  EXPECT_EQ(net::OK, cb.GetResult(cache->FlushDataForTest(cb.callback())));
+
+  cache.reset(new InfiniteCache);
+  cache->Init(path);
+  EXPECT_EQ(kNumEntries, cb.GetResult(cache->QueryItemsForTest(cb.callback())));
+}
+#endif