다수의 ESXi hosts 를 가진 shared storage 성능 저하 문제.
vmfs metadata locking 때문에 나타나는 현상.
## ESXi 의 vmkernel.log
2014-04-06T18:03:08.812Z cpu2:2934)DLX: 3901: vol ‘datastore’: [Req mode: 1] Not free; Lock [type 10c00001 offset 186707968 v 545, hb offset 3575808
gen 1263, mode 1, owner 52707286-f756fdcd-dd2b-d4856453dffe mtime 36619 nHld 0 nOvf 0]
## 위의 메시지와 관련된 KB(knowledge base) 내용
ESX/ESXi host locks a series of on-disk resource metadata structures delaying operations from other hosts (2052862)
http://kb.vmware.com/selfservice/microsites/search.do?language=en_US&cmd=displayKC&externalId=2052862
Under most conditions the delay is unnoticed operationally. However, the chance of this delay becoming apparent to user level operations increases under these conditions:
-Large number of hosts (>10) in a cluster attempting to allocate files on VMFS datastores with low % free space (< 10%).
-Power-off or power-on operations on many virtual machines in a short period of time.
-vMotion of virtual machines that involves VMFS datastores with low % free space (< 10%).
-High activity on disk trees that contain a lot of linked clones.
-High rate of growth with thin disk provisioning.
## 패치된 빌드 버전 정보
VMware ESXi 5.0, Patch Release ESXi500-201308001 (2053131)
http://kb.vmware.com/selfservice/microsites/search.do?language=en_US&cmd=displayKC&externalId=2053131
Release Date: August 29, 2013
Download Filename: ESXi500-201308001.zip
Build: 1254542 / 1197855 (Security-only)
Download Size: 614.4 MB
Host Reboot Required: Yes
Virtual Machine Migration or Shutdown Required: Yes
## 패치된 빌드 중 bugfix 된 내용
VMware ESXi 5.0, Patch ESXi500-201308401-BG: Updates esx-base (2053133)
http://kb.vmware.com/selfservice/microsites/search.do?language=en_US&cmd=displayKC&externalId=2053133
When you perform certain operations that directly or indirectly involve Virtual Machine File System (VMFS), usually in an ESXi cluster environment sharing large number of VMFS datastores, you might encounter the following issues:
-ESXi host stops responding intermittently
-ESXi host gets disconnected from the vCenter Server
-Virtual machine stops responding intermittently
-Microsoft Cluster Service (MSCS) stops responding resulting in failover
-Host communication errors during Site Recovery Manager (SRM) data recovery and failover tests