[SOLVED] Random slow

[mrav]

Hello,
I used Zimbra since two year without any problem.
last two week i have encontured this problem: when I click on message to see it, system taking a long time before showing.
This problem is random and when it happens, there is a java process that brings cpu to 100%.
I have search a solution into the forum but without success.
My system is a Centos 4.5 and kernel is 2.6.9-55.ELsmp i686.
Zimbra version is 5.0.9_GA_2533.RHEL4_20080814121143 FOSS edition.
System is into a Virtual Machine (VirtualIron) and it have assigned 4 Cpu e 2,5Gb of ram. Disk is into a San IBM DS3400 and hardware machine is an IBM Blade.
This is result of top:
Tasks: 105 total, 1 running, 104 sleeping, 0 stopped, 0 zombie
Cpu(s): 5.1% us, 8.3% sy, 0.0% ni, 86.1% id, 0.4% wa, 0.1% hi, 0.0% si
Mem: 2595124k total, 1178404k used, 1416720k free, 52604k buffers
Swap: 1572856k total, 0k used, 1572856k free, 405776k cached

iostat:
Linux 2.6.9-55.ELsmp (zimbra.aorg.local) 12/04/2008

avg-cpu: %user %nice %sys %iowait %idle
5.07 0.00 8.37 0.40 86.16

Device: tps Blk_read/s Blk_wrtn/s Blk_read Blk_wrtn
hda 10.43 51.77 190.13 868270 3188740
hda1 0.02 0.05 0.00 818 4
hda2 21.94 51.70 190.13 867052 3188736
sda 19.65 178.15 9.01 2987752 151129
sda1 173.40 178.14 9.01 2987592 151129
dm-0 21.93 51.64 190.13 866114 3188736
dm-1 0.00 0.02 0.00 360 0

In this system run only Zimbra.
Any Idea?
Thank's in advance.

[mrav]

Hi, problem depend from disk and vstools.
Thank's at all.