measure disk sort time (phys_offset)

include/libtorrent/disk_io_thread.hpp

@@ -172,6 +172,7 @@ namespace libtorrent
 			, average_write_time(0)
 			, average_hash_time(0)
 			, average_cache_time(0)
+			, average_sort_time(0)
 			, job_queue_length(0)
 		{}
 
@@ -208,6 +209,7 @@ namespace libtorrent
 		int average_write_time;
 		int average_hash_time;
 		int average_cache_time;
+		int average_sort_time;
 		int job_queue_length;
 	};
 	
@@ -448,6 +450,10 @@ namespace libtorrent
 		// scanning the cache for pieces to flush
 		sliding_average<512> m_cache_time;
 
+		// average time to ask for physical offset on disk
+		// and insert into queue
+		sliding_average<512> m_sort_time;
+
 		typedef std::multimap<size_type, disk_io_job> read_jobs_t;
 		read_jobs_t m_sorted_read_jobs;
 

src/disk_io_thread.cpp

@@ -344,6 +344,7 @@ namespace libtorrent
 		ret.average_write_time = m_write_time.mean();
 		ret.average_hash_time = m_hash_time.mean();
 		ret.average_cache_time = m_cache_time.mean();
+		ret.average_sort_time = m_sort_time.mean();
 		ret.job_queue_length = m_jobs.size() + m_sorted_read_jobs.size();
 
 		return ret;
@@ -1633,9 +1634,13 @@ namespace libtorrent
 #ifdef TORRENT_DISK_STATS
 					m_log << log_time() << " sorting_job" << std::endl;
 #endif
+					ptime sort_start = time_now_hires();
+
 					size_type phys_off = j.storage->physical_offset(j.piece, j.offset);
 					need_update_elevator_pos = need_update_elevator_pos || m_sorted_read_jobs.empty();
 					m_sorted_read_jobs.insert(std::pair<size_type, disk_io_job>(phys_off, j));
+
+					m_sort_time.add_sample(total_microseconds(time_now_hires() - sort_start));
 					continue;
 				}
 			}
@@ -1700,7 +1705,8 @@ namespace libtorrent
 
 			flush_expired_pieces();
 
-			m_cache_time.add_sample(total_microseconds(time_now_hires() - now));
+			ptime operation_start = time_now_hires();
+			m_cache_time.add_sample(total_microseconds(operation_start - now));
 
 			int ret = 0;
 
@@ -1970,7 +1976,6 @@ namespace libtorrent
 						break;
 					}
 
-					ptime read_start = time_now_hires();
 					disk_buffer_holder read_holder(*this, j.buffer);
 
 					bool hit;
@@ -2011,7 +2016,7 @@ namespace libtorrent
 					}
 					if (!hit)
 					{
-						m_read_time.add_sample(total_microseconds(time_now_hires() - read_start));
+						m_read_time.add_sample(total_microseconds(time_now_hires() - operation_start));
 					}
 					TORRENT_ASSERT(j.buffer == read_holder.get());
 					read_holder.release();

src/session.cpp

@@ -192,6 +192,9 @@ namespace libtorrent
 		// allow 500 files open at a time
 		set.file_pool_size = 500;
 
+		// don't update access time for each read/write
+		set.no_atime_storage = true;
+
 		// as a seed box, we must accept multiple peers behind
 		// the same NAT
 		set.allow_multiple_connections_per_ip = true;

src/session_impl.cpp

@@ -946,6 +946,7 @@ namespace aux {
 			":disk buffer allocations"
 			":disk hash time"
 			":disk cache time"
+			":disk sort time"
 			"\n\n", m_stats_logger);
 	}
 #endif
@@ -2715,7 +2716,7 @@ namespace aux {
 				  "%d\t%d\t%d\t%d\t%d\t%d\t%d\t%d\t%d\t%d\t"
 				  "%d\t%d\t%d\t%d\t%d\t%d\t%d\t%d\t%d\t%d\t"
 				  "%f\t%f\t%f\t%d\t%d\t%d\t%d\t%d\t%d\t%d\t"
-				  "%d\t%d\t%d\t%d\t%d\t%d\t%d\t%d\t%d\n"
+				  "%d\t%d\t%d\t%d\t%d\t%d\t%d\t%d\t%d\t%d\n"
 				, total_milliseconds(now - m_last_log_rotation) / 1000.f
 				, int(m_stat.total_upload() - m_last_uploaded)
 				, int(m_stat.total_download() - m_last_downloaded)
@@ -2795,6 +2796,7 @@ namespace aux {
 				, cs.total_used_buffers
 				, int(cs.average_hash_time)
 				, int(cs.average_cache_time)
+				, int(cs.average_sort_time)
 			);
 			m_last_cache_status = cs;
 			m_last_failed = m_total_failed_bytes;