GNOME Bugzilla – Bug 418170
Graphs don't scroll by smoothly
Last modified: 2013-02-04 23:19:08 UTC
The bug has been opened on https://launchpad.net/bugs/92118 "Binary package hint: gnome-system-monitor The graphs now have bezier curves and look beauuutiful :-) Here is an idea /feature request to compliment these sexy graphs: make them scroll smoothly, and independently from the selected sampling rate. Increasing the sampling rate (0.25s is the fastest) isn't a solution as graphs are still jerky, and it eats the CPU. For example I normally use a sampling rate of 1 second, which yields on an idle sytem (1.5GHz CPU) a CPU load of 8%, which is already significant. If I speed up the sampling rate to 0.25s, that's 4 times faster, I get 32% CPU load (!), which is also 4 times the previous load. So increasing the sampling rate clearly isn't a solution. So smooth scrolling graphs, and low CPU usage would be lovely :o) ProblemType: Bug Architecture: i386 Date: Wed Mar 14 03:33:52 2007 DistroRelease: Ubuntu 7.04 ExecutablePath: /usr/bin/gnome-system-monitor Package: gnome-system-monitor 2.18.0-0ubuntu1 ..."
Seems sensible. It could gather stats at the same samping rate, but re-draw the graph less frequently if CPU% is to high. What would be an acceptable CPU% usage ? You seem to say that 8% is already too much. 5% ?
Hello, I am the one who filed the bug in Ubuntu and that Seb kindly forwarded here. I think I was misunderstood ;-) My suggestion was to make the graphs scroll smoothly (regardless of sampling rate hence CPU load), for added sexyness. I am not that bothered by CPU load, since it is easy enough for the user, to select a sampling rate that yields an acceptable (to him) CPU usage. I only mentionned the CPU load fact, to suggest that increasing the sampling rate would not be a good idea/way to achieve smooth scrolling graphics, and that it would not work anyway, that it would still be jerky. In summary, the graphs ought to scroll smoothly REGARDLESS of sampling rate.
OK. the graph is redrawn on each update. I have no idea at all about how to do this.
This is supposed to be done in the next ubuntu release (hardy).
I tested it in Hardy a few days ago. I did notice that the graphs now scroll differently, but it's still not smooth. Well it does scrolls smoothly for one second, then I get a glitch, then smooth again, then a glitch, goes like this: tic-tic-tic-TAC,tic-tic-tic-TAC,tic-tic-tic-TAC, and so on. Still jerky then...
First of all, the initial bug report that was filed here is now completed, I had done that work a while ago. We now have two surfaces where one slides over the other, the background is redrawn on configure and the graph is redrawn once per time interval. Vincent, RE "tic-tic-tic-TAC,tic-tic-tic-TAC,tic-tic-tic-TAC" I fixed that bug in SVN before 2.22 was branched. Benoit, can we close this bug?
I think this bug has been fixed in the newer versions of system-monitor. Can this bug be closed? Also so that launchpad updates itself too in this way.
I don't want to be too negative, but the CPU hit from this fix is a bit extreme. Running the system monitor showing the smooth graph on this computer uses about 40% of the CPU time. I don't think this is acceptable for a tool that is supposed to be measuring CPU time. You could close the bug, but then open a new one for the performance problem perhaps. But I don't think this is at a stage where you can just call it fixed and forget about it.
*** Bug 503614 has been marked as a duplicate of this bug. ***
[Adding missing "QA Contact" entry so system monitor bug report changes can still be watched via the "Users to watch" list on https://bugzilla.gnome.org/userprefs.cgi?tab=email when the assignee is changed to an individual.]
As smooth scrolling has been implemented (that being the original requirement here), I am closing this bug. Comment 8 mentions that this bug can be closed, as long as the performance problem is treated somewhere, and does not get forgotten. The performance problem is being talked about in bug 636343, so I am closing this bug as fixed.