From: Steinar H. Gunderson <sgunderson@bigfoot.com>
Date: Thu, 29 Jun 2017 20:53:24 +0000 (+0200)
Subject: Only report disk space anew every second. Saves 20% CPU or so on the UI thread (!).
X-Git-Tag: 1.6.1~16
X-Git-Url: https://git.sesse.net/?p=nageru;a=commitdiff_plain;h=cfff356a1739a0ed600c34e2de7eb64150ddf94d

Only report disk space anew every second. Saves 20% CPU or so on the UI thread (!).
---

diff --git a/disk_space_estimator.cpp b/disk_space_estimator.cpp
index a196105..86e5e87 100644
--- a/disk_space_estimator.cpp
+++ b/disk_space_estimator.cpp
@@ -50,7 +50,12 @@ void DiskSpaceEstimator::report_write(const std::string &filename, uint64_t pts)
 		double bytes_per_second = double(st.st_size - measure_points.front().size) /
 			(pts - measure_points.front().pts) * TIMEBASE;
 		double seconds_left = free_bytes / bytes_per_second;
-		callback(free_bytes, seconds_left);
+
+		// Only report every second, since updating the UI can be expensive.
+		if (last_pts_reported == 0 || pts - last_pts_reported >= TIMEBASE) {
+			callback(free_bytes, seconds_left);
+			last_pts_reported = pts;
+		}
 	}
 
 	measure_points.push_back({ pts, st.st_size });
diff --git a/disk_space_estimator.h b/disk_space_estimator.h
index c5b63bf..73b392c 100644
--- a/disk_space_estimator.h
+++ b/disk_space_estimator.h
@@ -44,6 +44,7 @@ private:
 		off_t size;
 	};
 	std::deque<MeasurePoint> measure_points;
+	uint64_t last_pts_reported = 0;
 
 	// Metrics.
 	std::atomic<int64_t> metric_disk_free_bytes{-1};