Shlomi Fish <[email protected]> writes: > Hi all. > > I reported a bug in Amarok ( > https://bugs.kde.org/show_bug.cgi?id=288876 ) where it sometimes > consumes over 10% of my RAM on startup, and it was closed with this > comment: > > <<<< Well, there is the virtual memory but it is the residual memory > use that matters. Yours us just 371M which is absolutely correct. > FWIW: I suggest you read up some documentation on dynamic memory use > in Linux. In short: the more memory available, the more will be > used, the system distributes this evenly to the running processes > depending on their priority. > > Not a bug. >>>>> > > Well, I don't understand it. What is "residual memory" in this > context (as Google searches for it yields junk.), and why is still > OK that Amarok consumes so much.
Well, there are two issues here. 1. I suspect/assume that "residual memory" means "resident set" (someone confused "resident" with "residual"?). This is the total size of pages mapped in RAM, per process, without VM or process kernel data structures. This has been discussed here before, e.g., http://www.mail-archive.com/[email protected]/msg31797.html 2. What was it that you considered a bug? The screenshot of top in your bug report shows resident set size (a.k.a. RSS, RES field in top) of 387M, which is consistent with 12.9% of your total 3G of RAM. If this is your complaint (why the process uses so much RAM?) then someone did not read your report attentively enough - I mean, the response can be (mis)construed as "you've looked at a wrong field". At the same time, it is not at all clear why they should consider it a bug. Out of curiosity, I started amarok on my F14 box and its RSS is 90M (without doing anything at all). There are other processes (quite a few) running on the machine right now, and this may explain why it is smaller than in your case (you did a "clean" experment, didn't you?). The app may allocate and preload/cache all sorts of stuff if it can - if there is memory available, why withhold it? This is what they told you, in different words. Finally, I did egrep "^Vm" /proc/<pid>/status and the app's heap is almost 10 times larger than RSS, i.e., stuff was allocated but not mapped. Maybe this is what they had in mind when they said that RSS is what matters. Another datum - the size of shared libraries used, is also significantly (50%) more than RSS. And if you note that RSS counts shared pages as belonging to the process (since they are mapped into the process's virtual memory space) it stops looking so badly. Hope something is clearer than it used to be. -- Oleg Goldshmidt | [email protected] _______________________________________________ Linux-il mailing list [email protected] http://mailman.cs.huji.ac.il/mailman/listinfo/linux-il
