= 2011-04-04 =

== VMWare Server : IOWait Performance Tuning ==

 * 因為經常遇到 IOWait 的問題，所以找一下別人是怎麼解決的。
 * <參考> [http://mrpointy.wordpress.com/2008/02/14/gutsy-and-vmware-server-youre-in-for-some-pain/ Gutsy and Vmware-Server – you’re in for some pain]
 * 首先修改 /etc/vmware/config
{{{
--- /etc/vmware/config.bak	2011-04-04 22:21:13.000000000 +0800
+++ /etc/vmware/config	2011-04-06 10:20:42.000000000 +0800
@@ -22,4 +22,7 @@
 product.name = "VMware Server"
 # Beginning of the block added by the VMware VIX software
 vix.libdir = "/usr/lib/vmware-vix/lib"
+# 11-04-04: Enhance performance - by Jazz
+prefvmx.useRecommendedLockedMemSize = "TRUE"
+prefvmx.minVmMemPct = "100"
 # End of the block added by the VMware VIX software
}}}
 * 其次修改經常發生 IOWait 的虛擬機器 vmx 設定檔
{{{
#!diff
--- Trac_Pool.vmx.bak	2011-04-06 10:24:17.000000000 +0800
+++ Trac_Pool.vmx	2011-04-04 23:26:34.000000000 +0800
@@ -49,3 +49,8 @@
 debugStub.linuxOffsets = "0x0,0xffffffff,0x0,0x0,0x0,0x0,0x0,0x0,0x0,0x0,0x0,0x0,0x0,0x0"
 
 extendedConfigFile = "Trac_Pool.vmxf"
+
+sched.mem.pshare.enable = "FALSE"
+mainMem.useNamedFile = "FALSE"
+MemTrimRate = "0"
+MemAllowAutoScaleDown = "FALSE"
}}}
 * 另外，不確定是否因為我用單檔 VMDK 所以造成記憶體的 filesytem cache 太高，所以定期用 crontab 清掉一些 cache
{{{
0 * * * * /usr/sbin/ntpdate-debian > /dev/null 2>&1
0 * * * * echo 1 > /proc/sys/vm/drop_caches
5 * * * * echo 3 > /proc/sys/vm/drop_caches
}}}
 * 還可以用 vmware-vdiskmanager 進行虛擬硬碟的檢查跟重組、縮小 - <參考> [http://www.howtoforge.com/how-to-shrink-vmware-virtual-disk-files-vmdk How To Shrink VMware Virtual Disk Files (.vmdk)>
{{{
# 對 myDisk.vmdk 進行重組(defragment)
vmware-vdiskmanager -d myDisk.vmdk
# 把 myDisk.vmdk 釋出沒有用到的空白空間（shrink）
vmware-vdiskmanager -k myDisk.vmdk
# 把 sourceDisk.vmdk 拷貝成 type 為 0 (single growable virtual disk) 的 destinationDisk.vmdk
vmware-vdiskmanager -r sourceDisk.vmdk -t 0 destinationDisk.vmdk
# 把 myDisk.vmdk 容量擴大到 36GB
vmware-vdiskmanager -x 36GB myDisk.vmdk
}}}