Disk provison for new vSphere enviroment

Question

I'm deploying a vsphere environment with more than 200 new vm on 20TB datastore and stuck with disk provisioning. Eager zeroed was used before, but for 100 vm it will take a lot of time and i'm thinking about lazy zeroed.

Are there any differences for vm or potential issues with lazy zeroed? Most vms are Linux.

So it's a single host with just local DAS? Have you just considered 'thinning' them all? — Chopper3, Apr 15 '20 at 15:43
it is single host environment for application testing purposes before production. And i'm not considering thin provision, but lazy zeroed — KumarHamun, Apr 15 '20 at 15:52

score 5 · Accepted Answer · answered Apr 15 '20 at 15:30

5

Lazy zeroed provisioning just reserves the space, but doesn’t fill it with zeroes, so by first writing the allocated space on vmdk should be zeroed, what decreases the performance. The performance won’t be decreased on rewriting already existing blocks. You can use Thin Provisioning Lazy Zeroed with VMs without high IOPS requirements and Eager Zeroed with high performing.

More about the provisioning - https://www.vmwareblog.org/vmware-esxi-disk-provision-work-difference-one-better/

answered Apr 15 '20 at 15:30

batistuta09

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Thanks! what performance difference should i expect? – KumarHamun Apr 15 '20 at 15:34
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Initial write performance will be definitely much slower. I suggest create two test VMs (or one VM with two attached disks) – one with lazy zeroed and the second eager zeroed. After that just run benchmarking like fio or diskspd. – batistuta09 Apr 16 '20 at 08:15

Disk provison for new vSphere enviroment

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