Get visibility into stability file accumulation

components/browser_watcher/postmortem_report_collector.cc

 // Copyright 2016 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 "components/browser_watcher/postmortem_report_collector.h"
 
 #include <utility>
 
 #include "base/debug/activity_analyzer.h"
 #include "base/files/file_enumerator.h"
@@ skipping 152 matching lines @@
     const base::FilePath::StringType& debug_file_pattern,
     const std::set<base::FilePath>& excluded_debug_files,
     crashpad::CrashReportDatabase* report_database) {
   DCHECK_NE(true, debug_info_dir.empty());
   DCHECK_NE(true, debug_file_pattern.empty());
   DCHECK_NE(nullptr, report_database);
 
   // Collect the list of files to harvest.
   std::vector<FilePath> debug_files = GetDebugStateFilePaths(
       debug_info_dir, debug_file_pattern, excluded_debug_files);
+  UMA_HISTOGRAM_COUNTS_100("ActivityTracker.Collect.StabilityFileCount",
+                           debug_files.size());
 
   // Determine the crashpad client id.
   crashpad::UUID client_id;
   crashpad::Settings* settings = report_database->GetSettings();
   if (settings) {
     // If GetSettings() or GetClientID() fails client_id will be left at its
     // default value, all zeroes, which is appropriate.
     settings->GetClientID(&client_id);
   }
 
@@ skipping 52 matching lines @@
       LOG(ERROR) << "Failed to delete " << file.value();
     return status;
   }
   DCHECK_NE(nullptr, report_proto.get());
 
   // Prepare a crashpad report.
   CrashReportDatabase::NewReport* new_report = nullptr;
   CrashReportDatabase::OperationStatus database_status =
       report_database->PrepareNewCrashReport(&new_report);
   if (database_status != CrashReportDatabase::kNoError) {
+    // Assume this is recoverable: not deleting the file.
     LOG(ERROR) << "PrepareNewCrashReport failed";

[Sigurður Ásgeirsson, 2017/02/28 15:45:41]

Out of curiosity - how are these LOGs useful? Have you ever retrieved a log from
the field? Maybe it's better to use DLOG, and avoid bloating our shipped
binaries?

[manzagop (departed), 2017/02/28 16:07:39]

Done.

     return PREPARE_NEW_CRASH_REPORT_FAILED;
   }
   CrashReportDatabase::CallErrorWritingCrashReport
       call_error_writing_crash_report(report_database, new_report);
 
   // Write the report to a minidump.
   if (!WriteReportToMinidump(report_proto.get(), client_id, new_report->uuid,
                              reinterpret_cast<FILE*>(new_report->handle))) {
+    // Assume this is not recoverable and delete the file.
+    if (!base::DeleteFile(file, false))
+      LOG(ERROR) << "Failed to delete " << file.value();
     return WRITE_TO_MINIDUMP_FAILED;
   }
 
   // If the file cannot be deleted, do not report its contents. Note this can
   // lead to under reporting and retries. However, under reporting is
   // preferable to the over reporting that would happen with a file that
   // cannot be deleted.
   // TODO(manzagop): metrics for the number of non-deletable files.
   if (!base::DeleteFile(file, false)) {
     LOG(ERROR) << "Failed to delete " << file.value();
@@ skipping 140 matching lines @@
     StabilityReport* report,
     const crashpad::UUID& client_id,
     const crashpad::UUID& report_id,
     base::PlatformFile minidump_file) {
   DCHECK(report);
 
   return WritePostmortemDump(minidump_file, client_id, report_id, report);
 }
 
 }  // namespace browser_watcher