A database administrator has requested a disk for a virtual machine that will run an I/O intensive
database application on an ESXi 5.x host. Which two disk types will best fit the needs of the
application? (Choose two.)
A.
Raw Device Mapped Disk
B.
Thin Provisioned Disk
C.
Thick Provision Lazy Zeroed Disk
D.
Thick Provision Eager Zeroed Disk
Explanation:
http://www.vmware.com/pdf/Perf_Best_Practices_vSphere5.0.pdfpage 31, clearly
states that best performance is achieved using eager zeroed provisioned disks, even when VAAI
is available
I think C is correct too
If this is an IO intensive DB app then you don’t want to “wait” for the disk to be zeroed as needed.
C and D are correct.
Raw Device Mapped Disk use for compounds of the network. There is no word about the network. And two type RDM. etc.
http://www.vmware.com/pdf/Perf_Best_Practices_vSphere5.0.pdf page 31
“Lazy zeroed – … Subsequent writes, however, have the same
performance as on eager-zeroed thick disks.”
http://www.vmgu.ru/articles/vmware-esx-vsphere-vmdk-thin-thick
Но RDM не используется для повышения производительности – его производительность аналогична дискам vmdk в файловой системе VMFS.
But RDM is not used to improve performance – its performance is similar to the vmdk disks in the file system VMFS.