+#include "frame_on_disk.h"
+
+#include "shared/metrics.h"
+
+#include <atomic>
+#include <chrono>
+#include <assert.h>
#include <fcntl.h>
+#include <mutex>
#include <unistd.h>
-#include "frame_on_disk.h"
-
using namespace std;
+using namespace std::chrono;
+
+namespace {
+
+// There can be multiple FrameReader classes, so make all the metrics static.
+once_flag frame_metrics_inited;
+
+atomic<int64_t> metric_frame_opened_files{ 0 };
+atomic<int64_t> metric_frame_closed_files{ 0 };
+atomic<int64_t> metric_frame_read_bytes{ 0 };
+atomic<int64_t> metric_frame_read_frames{ 0 };
+
+Summary metric_frame_read_time_seconds;
+
+} // namespace
+
+FrameReader::FrameReader()
+{
+ call_once(frame_metrics_inited, [] {
+ global_metrics.add("frame_opened_files", &metric_frame_opened_files);
+ global_metrics.add("frame_closed_files", &metric_frame_closed_files);
+ global_metrics.add("frame_read_bytes", &metric_frame_read_bytes);
+ global_metrics.add("frame_read_frames", &metric_frame_read_frames);
+
+ vector<double> quantiles{ 0.01, 0.1, 0.25, 0.5, 0.75, 0.9, 0.99 };
+ metric_frame_read_time_seconds.init(quantiles, 60.0);
+ global_metrics.add("frame_read_time_seconds", &metric_frame_read_time_seconds);
+ });
+}
FrameReader::~FrameReader()
{
if (fd != -1) {
close(fd);
+ ++metric_frame_closed_files;
}
}
-string FrameReader::read_frame(FrameOnDisk frame)
+namespace {
+
+string read_string(int fd, size_t size, off_t offset)
{
+ string str;
+ str.resize(size);
+ size_t str_offset = 0;
+ while (str_offset < size) {
+ int ret = pread(fd, &str[str_offset], size - str_offset, offset + str_offset);
+ if (ret <= 0) {
+ perror("pread");
+ abort();
+ }
+
+ str_offset += ret;
+ }
+ return str;
+}
+
+} // namespace
+
+FrameReader::Frame FrameReader::read_frame(FrameOnDisk frame, bool read_video, bool read_audio)
+{
+ assert(read_video || read_audio);
+ steady_clock::time_point start = steady_clock::now();
+
if (int(frame.filename_idx) != last_filename_idx) {
if (fd != -1) {
close(fd); // Ignore errors.
+ ++metric_frame_closed_files;
}
string filename;
fd = open(filename.c_str(), O_RDONLY);
if (fd == -1) {
perror(filename.c_str());
- exit(1);
+ abort();
}
// We want readahead. (Ignore errors.)
posix_fadvise(fd, 0, 0, POSIX_FADV_SEQUENTIAL);
last_filename_idx = frame.filename_idx;
+ ++metric_frame_opened_files;
}
- string str;
- str.resize(frame.size);
- off_t offset = 0;
- while (offset < frame.size) {
- int ret = pread(fd, &str[offset], frame.size - offset, frame.offset + offset);
- if (ret <= 0) {
- perror("pread");
- exit(1);
- }
-
- offset += ret;
+ Frame ret;
+ if (read_video) {
+ ret.video = read_string(fd, frame.size, frame.offset);
}
- return str;
+ if (read_audio) {
+ ret.audio = read_string(fd, frame.audio_size, frame.offset + frame.size);
+ }
+
+ steady_clock::time_point stop = steady_clock::now();
+ metric_frame_read_time_seconds.count_event(duration<double>(stop - start).count());
+
+ metric_frame_read_bytes += frame.size;
+ ++metric_frame_read_frames;
+
+ return ret;
}