Java issues

[mhammett]

I really wish people wouldn't code things in Java.

I've been working with Zimbra. First I had CentOS with OpenVZ and Java had memory issues. I largely mitigated the issues, but not comfortable for a production environment. I tried CentoS with KVM and had CPU usage issues. I saw some issues with CentOS, KVM, and Java... so I switched to a Debian KVM container. Same CPU usage issues.

With nothing going on (beginning LDAP server with no data or things attached to it), the CPU usage randomly goes to 100% on an AMD Phenom processor. Well, 100% on the container. it chews up an entire core on the physical processor.

I prefer running the stable Proxmox kernels, but might a different kernel give me better luck?

Fenix:~# pveversion -v
pve-manager: 1.6-5 (pve-manager/1.6/5261)
running kernel: 2.6.18-2-pve
proxmox-ve-2.6.18: 1.5-5
pve-kernel-2.6.18-2-pve: 2.6.18-5
qemu-server: 1.1-22
pve-firmware: 1.0-9
libpve-storage-perl: 1.0-14
vncterm: 0.9-2
vzctl: 3.0.24-1pve4
vzdump: 1.2-8
vzprocps: 2.0.11-1dso2
vzquota: 3.0.11-1
pve-qemu-kvm-2.6.18: 0.9.1-8

 

[JustaGuy]

it chews up an entire core on the physical processor.

Is this just with your Java application, or with anything that makes use of Java?

Could another version of Java maybe not do the same?

might a different kernel give me better luck?

It could, it's not the PVE default anymore- 2.6.32 has received the Proxmox seal of stability apparently. I use 2.6.35 for KSM so I can't say much on it.

On mine, 2.6.32 does a little better than 2.6.35, if I want to do without KSM:

2.6.32:

CPU BOGOMIPS:      53201.14
REGEX/SECOND:      839968

2.6.35:

CPU BOGOMIPS:      53199.32
REGEX/SECOND:      797093

I don't have any data on 2.6.18 to compare.

 

[mhammett]

I'm not sure if a different Java version would be any different. I'm not sure how to change any of that in Linux, nor if it would negatively affect the application. Well, any more than it already is.

2.6.32 may be the default, but http://pve.proxmox.com/wiki/Proxmox_VE_Kernel says that the OpenVZ kernel is from the development branch.

 

[tom]

if you use openvz, keep the 2.6.18er branch, we regularly update these kernel branch (see pvetest for latest).