Re: Problem with memory (unix) allocation to JVM running Java program

Dundonald wrote:
> I'm attempting to run a very simple Java program on unix box using
> command:
>
> java -jar HelloWorld.jar
>
> and experience the following error
>
> Error occurred during initialization of VM
> Could not reserve enough space for object heap
> Could not create the Java virtual machine.
>
> If I run the "top" and "free" unix commands I can't see why there
> might be a problem freeing up memory to allocate to the JVM, unless
> I'm missing something obvious. Any ideas please help. Thanks.
>
> See below for "top" and "free" output:
>
> top:
>
> top - 07:57:22 up 21 days, 14:42, 3 users, load average: 0.16, 0.07,
> 0.02
> Tasks: 46 total, 1 running, 45 sleeping, 0 stopped, 0 zombie
> Cpu(s): 0.1% us, 0.1% sy, 0.0% ni, 99.8% id, 0.0% wa, 0.0% hi,
> 0.0% si
> Mem: 6097220k total, 6081344k used, 15876k free, 12584k
> buffers
> Swap: 12586916k total, 6277504k used, 6309412k free, 355436k
> cached
>
> PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+
> COMMAND
> 1 root 16 0 1628 516 492 S 0 0.0 0:03.66
> init
> 30158 root 15 0 1532 512 444 S 0 0.0 0:08.01
> syslogd
> 30175 root 16 0 4012 796 708 S 0 0.0 0:11.42
> sshd
> 30193 root 18 0 2080 600 596 S 0 0.0 0:00.00
> xinetd
> 30209 root 16 0 3716 296 260 S 0 0.0 0:00.00
> vsftpd
> 30285 root 18 0 2152 896 892 S 0 0.0 0:00.00
> mysqld_safe
> 30331 mysql 16 0 123m 4856 3036 S 0 0.1 1:02.25
> mysqld
> 30508 cyrus 16 0 4424 960 860 S 0 0.0 0:01.50 cyrus-
> master
> 30523 cyrus 18 0 29420 1488 1484 S 0 0.0 0:00.00
> imapd
> 30524 cyrus 17 0 29420 1488 1484 S 0 0.0 0:00.00
> imapd
> 30525 cyrus 18 0 29192 1488 1484 S 0 0.0 0:00.00
> pop3d
> 30527 cyrus 18 0 29192 1484 1484 S 0 0.0 0:00.00
> pop3d
> 30533 cyrus 18 0 29420 1488 1484 S 0 0.0 0:00.00
> imapd
> 30535 cyrus 18 0 29192 1488 1484 S 0 0.0 0:00.00
> pop3d
> 30626 root 16 0 5104 1344 1264 S 0 0.0 0:01.01
> master
> 30636 postfix 15 0 5204 1352 1292 S 0 0.0 0:00.11
> nqmgr
> 30645 cyrus 17 0 29420 1488 1484 S 0 0.0 0:00.00
> imapd
> 30646 cyrus 18 0 29420 1488 1484 S 0 0.0 0:00.00
> imapd
> 30647 cyrus 18 0 29420 1488 1484 S 0 0.0 0:00.00
> imapd
> 30648 cyrus 17 0 29192 1488 1484 S 0 0.0 0:00.00
> pop3d
> 30704 root 23 0 296m 39m 4120 S 0 0.7 4:42.30
> java
> 31817 root 16 0 49580 15m 7848 S 0 0.3 0:16.25
> httpd
> 31837 root 16 0 2480 592 544 S 0 0.0 0:00.06
> crond
> 31867 root 18 0 4052 540 536 S 0 0.0 0:00.00
> saslauthd
> 31868 root 18 0 4052 228 224 S 0 0.0 0:00.00
> saslauthd
> 20271 tomcat 17 0 452m 79m 4592 S 0 1.3 11:32.21
> java
> 32765 cyrus 18 0 29328 1652 1648 S 0 0.0 0:00.00
> lmtpd
> 7501 root 16 0 39384 6156 140 S 0 0.1 0:00.00
> httpd
> 7510 apache 15 0 49692 10m 2648 S 0 0.2 0:00.15
> httpd
> 13886 apache 15 0 49724 10m 2676 S 0 0.2 0:00.12
> httpd
> 13908 apache 15 0 49724 10m 2636 S 0 0.2 0:00.15
> httpd
> 11293 root 17 0 6632 1980 1628 S 0 0.0 0:00.01
> sshd
>
> free:
>
> total used free shared buffers
> cached
> Mem: 6097220 6081544 15676 0 30924
> 356504
> -/+ buffers/cache: 5694116 403104
> Swap: 12586916 6277504 6309412
>
>
I've had similar problems in NetBSD when I didn't properly set the
memory using ulimit. I don't remember the details, but it basically was
set to "unlimited" and that let the JVM think it could allocated
infinity :-)

Also, try playing with the -X setting (java -X for more help)


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