issue with limiting java's memory usage

[Patrick Lamaiziere]

Le Sun, 29 Jan 2012 19:34:11 +0000,
Alexander Best <arundel at freebsd.org> a écrit :

> hi there,

Hello,

> maybe i'm missing something obvious, but i don't quite understand the
> following top(1) output:
> 
> last pid: 13875;  load averages:  0.73,  0.75,  0.68
> 65 processes:  2 running, 62 sleeping, 1 waiting
> CPU 0: 19.5% user,  0.0% nice, 13.3% system,  0.0% interrupt, 67.2%
> idle CPU 1: 20.3% user,  0.0% nice,  7.8% system,  0.0% interrupt,
> 71.9% idle Mem: 1365M Active, 185M Inact, 323M Wired, 69M Cache, 213M
> Buf, 32M Free Swap: 10G Total, 2494M Used, 7746M Free, 24% Inuse, 4K
> In
> 
>   PID    UID    THR PRI NICE   SIZE    RES STATE   C   TIME   WCPU
> COMMAND 6913   1001     32  20    0  4252M  1312M uwait   0  18.3H
> 39.06% /usr/local/diablo-jdk1.6.0/bin/java -Xmx512m -jar JDownloade
> 
> ...how can the size of the resident memory of pid 6913 be > 512
> megabytes?

I don't know but you can inspect the java application with the java
console (jconsole). There are several stats on memory usage.

With JDownloader (doing nothing), I see 57 MB of "non heap memory
usage", and "only" 30 MB of heap memory.

Regards.