Issue Description
Virtual host copy documents from S2600 to FujitsuDX400, too slow, IO speed is about 1.2Mb/s.
User condition:
Storage system: Huawei S2600
Third party storage: FujitsuDX400
Host system: Windows 2003,VMWare ESX
Topo structure:
Handling Process
Configure lun to force write back through ISM.
OceanStor: admin> showlun -i 0
=====================================================================
LUN Information
---------------------------------------------------------------------
ID | 0
Name | Lun000_Vmware-0
Status | Normal
Capacity(MB) | 1048576
Stripe Unit Size(KB) | 64
RAID Group ID | 0
Format Progress(%) | --
Ascription Controller | A
Working Controller | A
Cache Prefetch Strategy | Intelligent
Cache Write Strategy | Write back mandatory; No mirroring
Running Cache Write Strategy | Write back; No mirroring
Extendable Capacity(MB) | 0
Extended Capacity(MB) | 0
=====================================================================
Root Cause
Login on storage through cli and check S2600 log information
OceanStor: admin> showsys
=====================================================
System Information
---------------------------------------------------------
System Name |
Device Model | OceanStor S2600
Current System Mode | Single Controller Fault
Location |
System Time | 2011-05-24 15:31:04
Device Serial Number | 210231G324Z097000004
Product Version | V100R001C02
iSCSI Device Name | iqn.2006-08.com.huawei:oceanstor:21000022a100d
| 031:notconfig
=====================================================
OceanStor: admin> showlun -i 0
==============================================================
LUN Information
--------------------------------------------------------------
ID | 0
Name | Lun000_Vmware-0
Status | Normal
Capacity(MB) | 1048576
Stripe Unit Size(KB) | 64
RAID Group ID | 0
Format Progress(%) | --
Ascription Controller | A
Working Controller | A
Cache Prefetch Strategy | Intelligent
Cache Write Strategy | Write back; No mirroring
Running Cache Write Strategy | Write through; No mirroring
Extendable Capacity(MB) | 0
Extended Capacity(MB) | 0
==============================================================
System information is abnormal, single controller fault.
Lun configuration is abnormal, lun configuration is write back, function is write through.
This S2600 is old version single controller storage, it has no BBU. It should be PDU, but in fact user does not configure PDU.
Then S2600 lose part of battery , when setting LUN cache to write back, S2600 can not find battery protection, so in order to protect data , it modify cache to write through , IO capability declines seriously.
Suggestions
Face to old S2600 single controller ,you need to configure lun to force write back