get your geekon with ron - session two: local storage vs centralized storage models
DESCRIPTION
Join virtualization expert and industry veteran Ron Oglesby as he discusses local storage vs centralized storage models for VDI, including the arguments for and against local storage in VDI environments, a review of converged platform models (ie Nutanix) for VDI, and SSD tips and tricksTRANSCRIPT
GeekOn Discussion:Local Disk vs ‘The SAN’
forVDI Storage
Ron Oglesby @ronoglesby #GeekOn
AgendaWho cares about this session anyway?
Why is disk so important in VDI? What are the key concepts to understand about VDI and
Storage
Then… Why Local Storage rules for VDI Why Local Storage Blows and You should ONLY use SAN
storage for VDI
Disk for Desktops? Who cares?How many disks does it take to support 25 desktops?
Disk IO Understanding Limitations
Some References!
http://www.techrepublic.com/blog/datacenter/calculate-iops-in-a-storage-array/2182
http://www.yellow-bricks.com/2009/12/23/iops/
Desktop IO Requirements?Read:Write ratio can be as high as 50:50
60:40 to 70:30 is typical
Light Users = 4-5 IOpsMedium Users = 8-10 IOpsHeavy Users = 14-20 IOps
So if you have 50 medium users 400-500 Sustained IOps
So if you have 75 users/server? 750 IO? 4 disks before RAID penalty?! 8-10 or more after penalty?
But what about boot / login storms?
Boot/Login StormsAt boot and login IO can be extreme
Even a medium user can generate 90-100 IO at login (why is that 100 IO a ‘magic’ number?)
Boot storms can be even worse
The “good” thing about a boot storm is that it is typically 90% Read! No RAID penalty Caching Helps
Still must be planned for.
Disk Costs and VDIDell 143 GB SAS 15K SAS Drive = $Dell 100 GB SSD Drive =$$EqualLogic SAS drives $$EqualLogic SATA drives = $EqualLogic SSD drives= $$$Windows 7 “Thick Provisioned” 20-35GBWindows 7 Linked-Clone = 8-10GB
Local Storage is the Solution to this Problem
Local StorageStart with these questions:
How many of you boot your normal desktops from the SAN?
How many of you boot your terminal servers from the SAN?
How many of you have an extremely short SLA on recovering your desktops?
Copyright © 2010 Unidesk Corporation. All Rights Reserved. www.unidesk.com
Why do people talk down local DASStorage companies make a lot of money selling
centralized disk and the software around it. More power to them!
Hypervisor’s “BIG” features require centralized storage- helps push all that higher end licensing
Tools supplied by hypervisor vendors don’t work without centralized storage.
Local Storage is about Perf vs CostDell PCs can cost as little as $350!Performance requirements require High end diskWritable GB cost local vs SAN (SAS 15k)
Writable GB cost local vs SAN (SSD)
Why pay for centralized storage for a desktop?!
RAID 1 143GB Drives $5/GB – SAN SSD $30-70/GB
RAID 1 143GB Drives $5/GB – SAN 15K $10-30/GB
That’s ALL BS
SAN is the Solution to this Problem
Local Storage is too limiting
Things this guy isn't telling you!HA, DRS, FT, E-I, E-I –OH…. Not available with local
disk!
Copyright © 2010 Unidesk Corporation. All Rights Reserved. www.unidesk.com
Local/CHEAP SSD isn't that great. IO can be handle cost effectively on the SANStorage Tiering/Data movement all but impossible
with local diskDynamic Capacity/Cloud? Not happening with local
disk.
You might not even have enough spindles!
All the features you love…Do I really need to detail them all?HADRSFTSRMStorage vMotionEtcEtc
Spindle Count???50 users per server at 20 IO each= 1000 Iops100 users/server @ 10…Boot / Login Storms?RAID Penalty for writes?
DL 360’s have 6 drive bays. 15K drives at 180 IO each 1080 IOps before RAID penalty?
Are you a Blade shop?Probably wont even get enough spindles in a server
“Cheap” SSD IssuesSo you move to SSD instead of rotating disk…$$$$ 149 GB SSD on Dell 610 $4,599.00$$ 100 GB SSD on Dell 610 $1,949.00Compare to 146GB at $359 on the same server.Can you even get enough writable space on those
SSD?
Better to use SSD for just hot data rather than all data
Handle the IO with mixed disksLeverage Hybrid Arrays
EqualLogic XVS EMC FAST Systems
SSD / EFD can be used for HOT dataSmart systems will MOVE the dataCan also be used for writes!
What about that whole Dynamic Cloud?Data Tiering
About placing data on the type of disk it NEEDS. Not fixed provisioning
Moving data from slow, to fast to REALLY fast disks Only moving small parts of data not whole VMDKs?!?!
Elasticity in the VM environment Dynamic increases/decreases in capacity Provisioning times increase – sometimes dramatically Recovery and flexibility in the toilet
So what does Unidesk think?We don’t care….So what to we do?
Copyright © 2010 Unidesk Corporation. All Rights Reserved. www.unidesk.com
[email protected]@ronoglesby
Open Q&A