ServiceWorker: Migrate the script cache backend from BlockFile to Simple

content/browser/service_worker/service_worker_disk_cache_migrator.cc

 // Copyright 2015 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.
 
 #include "content/browser/service_worker/service_worker_disk_cache_migrator.h"
 
 #include "base/barrier_closure.h"
 #include "base/files/file_util.h"
 #include "base/location.h"
 #include "base/memory/ref_counted.h"
+#include "base/metrics/histogram_macros.h"
 #include "base/strings/string_number_conversions.h"
 #include "base/task_runner_util.h"
+#include "base/time/time.h"
 #include "content/common/service_worker/service_worker_types.h"
 #include "net/base/io_buffer.h"
 #include "net/base/net_errors.h"
 #include "net/disk_cache/disk_cache.h"
 
 namespace content {
 
 namespace {
 
 // Disk cache entry data indices (Copied from appcache_diskcache.cc).
@@ skipping 11 matching lines @@
     return SERVICE_WORKER_OK;
 
   // Android has alredy used the Simple backend. Just move the existing
   // diskcache files to a new location.
   if (base::Move(src_path, dest_path))
     return SERVICE_WORKER_OK;
   return SERVICE_WORKER_ERROR_FAILED;
 }
 #endif  // defined(OS_ANDROID)
 
+void RecordMigrationResult(ServiceWorkerStatusCode status) {
+  UMA_HISTOGRAM_ENUMERATION("ServiceWorker.DiskCacheMigrator.MigrationResult",
+                            status, SERVICE_WORKER_ERROR_MAX_VALUE);
+}
+
+void RecordNumberOfMigratedResources(size_t migrated_resources) {
+  UMA_HISTOGRAM_CUSTOM_COUNTS(
+      "ServiceWorker.DiskCacheMigrator.NumberOfMigratedResources",
+      migrated_resources, 1, 1000, 50);

[Alexei Svitkine (slow), 2015/06/16 15:31:15]

This looks like an UMA_HISTOGRAM_COUNTS_1000, which doesn't exist - but
apparently lots of people already use these params:

https://code.google.com/p/chromium/codesearch#search/&q=%221,%201000,%2050)%2...

Can you add UMA_HISTOGRAM_COUNTS_1000() to histogram_macros.h?

[nhiroki, 2015/06/16 16:32:26]

Done.

+}
+
+void RecordMigrationTime(const base::TimeDelta& time) {
+  UMA_HISTOGRAM_MEDIUM_TIMES("ServiceWorker.DiskCacheMigrator.MigrationTime",
+                             time);
+}
+
 }  // namespace
 
 // A task to move a cached resource from the src DiskCache to the dest
 // DiskCache. This is owned by ServiceWorkerDiskCacheMigrator.
 class ServiceWorkerDiskCacheMigrator::Task {
  public:
   Task(InflightTaskMap::KeyType task_id,
        int64 resource_id,
        int32 data_size,
        ServiceWorkerDiskCache* src,
@@ skipping 203 matching lines @@
       max_disk_cache_size_(max_disk_cache_size),
       disk_cache_thread_(disk_cache_thread),
       weak_factory_(this) {
 }
 
 ServiceWorkerDiskCacheMigrator::~ServiceWorkerDiskCacheMigrator() {
 }
 
 void ServiceWorkerDiskCacheMigrator::Start(const StatusCallback& callback) {
   callback_ = callback;
+  start_time_ = base::TimeTicks::Now();
 
 #if defined(OS_ANDROID)
   PostTaskAndReplyWithResult(
       disk_cache_thread_.get(), FROM_HERE,
       base::Bind(&MigrateForAndroid, src_path_, dest_path_),
       base::Bind(&ServiceWorkerDiskCacheMigrator::Complete,
                  weak_factory_.GetWeakPtr()));
 #else
   PostTaskAndReplyWithResult(
       disk_cache_thread_.get(), FROM_HERE,
@@ skipping 133 matching lines @@
     ServiceWorkerStatusCode status) {
   DCHECK(inflight_tasks_.Lookup(task_id));
   inflight_tasks_.Remove(task_id);
 
   if (status != SERVICE_WORKER_OK) {
     inflight_tasks_.Clear();
     Complete(status);
     return;
   }
 
+  ++number_of_migrated_resources_;
+
   if (pending_task_) {
     RunPendingTask();
     OpenNextEntry();
     return;
   }
 
   if (is_iterating_)
     return;
 
   if (inflight_tasks_.IsEmpty())
     Complete(SERVICE_WORKER_OK);
 }
 
 void ServiceWorkerDiskCacheMigrator::Complete(ServiceWorkerStatusCode status) {
   DCHECK(inflight_tasks_.IsEmpty());
-  // TODO(nhiroki): Add UMA for the result of migration.
+  if (status == SERVICE_WORKER_OK) {
+    RecordMigrationTime(base::TimeTicks().Now() - start_time_);
+    RecordNumberOfMigratedResources(number_of_migrated_resources_);
+  }
+  RecordMigrationResult(status);
 
   src_.reset();
   dest_.reset();
   callback_.Run(status);
 }
 
 }  // namespace content