[SoftDux]

Hi,

I have a problematic CentOS XEN server and hope someone could point me in the right direction to optimize it a bit.

The server runs on a Core2Quad 9300, with 8GB RAM (max motherboard can take, 1U chassis) on an Intel motherboard with a 1TB SATA HDD.

dom0 is set to 512MB limit with a few small XEM VM's running:

Code:

root@zaxen01:[~]$ xm list
Name                                      ID Mem(MiB) VCPUs State   Time(s)
Domain-0                                   0      512     4 r-----     96.5
actionco.vm                                3     1519     1 -b----     14.8
byracers.vm                                4      511     1 -b----     85.7
ns1                                        5      511     1 -b----     22.3
picturestravel                            6      255     1 -b----     13.3
rafttheworld                               7      255     1 -b----     11.3
zafepres.vm                                8      511     1 -b----     19.0

the server itself seems to eat up a lot of resources:

Code:

root@zaxen01:[~]$ free -m
             total       used       free     shared    buffers     cached
Mem:           512        472         39          0         13        215
-/+ buffers/cache:        244        268
Swap:         4095          0       4095

Yet, it only has XEN, Webmin (since it's a CloudMin XEN server), Exim, Apache and a few other services running:

Code:

root@zaxen01:[~]$ chkconfig --list |grep "3:on" |awk '{print $1}' |sort
acpid
auditd
crond
csf
dhcpd
exim
haldaemon
httpd
iptables
iscsi
iscsid
kudzu
lfd
lvm2-monitor
mdmonitor
network
qemu
restorecond
setroubleshoot
smartd
snmpd
sshd
syslog
sysstat
webmin
xend
xendomains

Is there anything I can optimize on such a server?



The server runs CentOS 5.5 x64:

root@zaxen01:[~]$ cat /etc/redhat-release
CentOS release 5.5 (Final)

root@zaxen01:[~]$ uname -a
Linux zaxen01.softdux.com 2.6.18-194.32.1.el5xen #1 SMP Wed Jan 5 18:44:24 EST 2011 x86_64 x86_64 x86_64 GNU/Linux

with Xen version 3.1.2-194.32.1.el5


And there's the xm dmesg output:

Code:

Xen version 3.1.2-194.32.1.el5 (mockbuild@centos.org) (gcc version 4.1.2 20080704 (Red Hat 4.1.2-48)) Wed Jan  5 17:43:03 EST 2011
 Latest ChangeSet: unavailable

(XEN) Command line: dom0_mem=512M
(XEN) Video information:
(XEN)  VGA is text mode 80x25, font 8x16
(XEN)  VBE/DDC methods: V2; EDID transfer time: 1 seconds
(XEN) Disc information:
(XEN)  Found 1 MBR signatures
(XEN)  Found 1 EDD information structures
(XEN) Xen-e820 RAM map:
(XEN)  0000000000000000 - 000000000008f000 (usable)
(XEN)  000000000008f000 - 00000000000a0000 (reserved)
(XEN)  00000000000e0000 - 0000000000100000 (reserved)
(XEN)  0000000000100000 - 00000000cf53f000 (usable)
(XEN)  00000000cf53f000 - 00000000cf54b000 (reserved)
(XEN)  00000000cf54b000 - 00000000cf620000 (usable)
(XEN)  00000000cf620000 - 00000000cf6e8000 (ACPI NVS)
(XEN)  00000000cf6e8000 - 00000000cf6ec000 (usable)
(XEN)  00000000cf6ec000 - 00000000cf6f1000 (ACPI data)
(XEN)  00000000cf6f1000 - 00000000cf6f2000 (usable)
(XEN)  00000000cf6f2000 - 00000000cf6ff000 (ACPI data)
(XEN)  00000000cf6ff000 - 00000000cf700000 (usable)
(XEN)  00000000cf700000 - 00000000d0000000 (reserved)
(XEN)  00000000fff00000 - 0000000100000000 (reserved)
(XEN)  0000000100000000 - 0000000230000000 (usable)
(XEN) System RAM: 8181MB (8378020kB)
(XEN) Xen heap: 13MB (13720kB)
(XEN) Domain heap initialised: DMA width 32 bits
(XEN) Processor #0 7:7 APIC version 20
(XEN) Processor #2 7:7 APIC version 20
(XEN) Processor #1 7:7 APIC version 20
(XEN) Processor #3 7:7 APIC version 20
(XEN) IOAPIC[0]: apic_id 2, version 32, address 0xfec00000, GSI 0-23
(XEN) Enabling APIC mode:  Flat.  Using 1 I/O APICs
(XEN) Using scheduler: SMP Credit Scheduler (credit)
(XEN) Detected 2485.797 MHz processor.
(XEN) HVM: VMX enabled
(XEN) VMX: MSR intercept bitmap enabled
(XEN) I/O virtualisation disabled
(XEN) CPU0: Intel(R) Core(TM)2 Quad  CPU   Q9300  @ 2.50GHz stepping 07
(XEN) Booting processor 1/2 eip 90000
(XEN) CPU1: Intel(R) Core(TM)2 Quad  CPU   Q9300  @ 2.50GHz stepping 07
(XEN) Booting processor 2/1 eip 90000
(XEN) CPU2: Intel(R) Core(TM)2 Quad  CPU   Q9300  @ 2.50GHz stepping 07
(XEN) Booting processor 3/3 eip 90000
(XEN) CPU3: Intel(R) Core(TM)2 Quad  CPU   Q9300  @ 2.50GHz stepping 07
(XEN) Total of 4 processors activated.
(XEN) ENABLING IO-APIC IRQs
(XEN)  -> Using new ACK method
(XEN) Platform timer overflows in 2 jiffies.
(XEN) Platform timer is 1.193MHz PIT
(XEN) Brought up 4 CPUs
(XEN) *** LOADING DOMAIN 0 ***
(XEN) elf_parse_binary: phdr: paddr=0xffffffff80200000 memsz=0x2f4d70
(XEN) elf_parse_binary: phdr: paddr=0xffffffff804f4d80 memsz=0x14c510
(XEN) elf_parse_binary: phdr: paddr=0xffffffff80642000 memsz=0xc08
(XEN) elf_parse_binary: phdr: paddr=0xffffffff80644000 memsz=0x11be8c
(XEN) elf_parse_binary: memory: 0xffffffff80200000 -> 0xffffffff8075fe8c
(XEN) elf_xen_parse_note: GUEST_OS = "linux"
(XEN) elf_xen_parse_note: GUEST_VERSION = "2.6"
(XEN) elf_xen_parse_note: XEN_VERSION = "xen-3.0"
(XEN) elf_xen_parse_note: VIRT_BASE = 0xffffffff80000000
(XEN) elf_xen_parse_note: PADDR_OFFSET = 0xffffffff80000000
(XEN) elf_xen_parse_note: ENTRY = 0xffffffff80200000
(XEN) elf_xen_parse_note: HYPERCALL_PAGE = 0xffffffff80206000
(XEN) elf_xen_parse_note: FEATURES = "writable_page_tables|writable_descriptor_tables|auto_translated_physmap|pae_pgdir_above_4gb|supervisor_mode_k
ernel"
(XEN) elf_xen_parse_note: LOADER = "generic"
(XEN) elf_xen_addr_calc_check: addresses:
(XEN)     virt_base        = 0xffffffff80000000
(XEN)     elf_paddr_offset = 0xffffffff80000000
(XEN)     virt_offset      = 0x0
(XEN)     virt_kstart      = 0xffffffff80200000
(XEN)     virt_kend        = 0xffffffff8075fe8c
(XEN)     virt_entry       = 0xffffffff80200000
(XEN)  Xen  kernel: 64-bit, lsb, compat32
(XEN)  Dom0 kernel: 64-bit, lsb, paddr 0xffffffff80200000 -> 0xffffffff8075fe8c
(XEN) PHYSICAL MEMORY ARRANGEMENT:
(XEN)  Dom0 alloc.:   0000000222000000->0000000224000000 (122880 pages to be allocated)
(XEN) VIRTUAL MEMORY ARRANGEMENT: