Is a single mechanical drive just too slow these days?

[m_cozzy]

So recently I decided to simplify my pc by removing my adaptec 5405 raid card with 4 x 1tb disks in raid5 and instead used onboard raid1 for the important stuff and the other 2 separate drives for data I could afford to loose. The os is on an old intel 80gb ssd.
This isnt modern kit, the adaptec is from 2009 & samsung f1's must be a good few years old.
Performance plummeted VMware workstation was barely usable trying to open a single virtual machine let alone multiple, games took an age to load, just a frustrating laggy experience.
So last night the adaptec went back in using the 4 drives as raid 10 with a cheapy 2.5 1tb drive to store media I wasnt bothered about loosing.
Hello performance again

I guess the question is, how do others cope? is a discrete raid controller or an ssd an absolute must for reasonable performance, or are modern drives that much faster than my old stuff?

 

[KelDG]

Depends on what you are doing really, day to day, yep its fine for just browsing and gaming. With the better sleep function in windows 7 I don't even have a start up time, its just on in 2 or 3 seconds.

What you are doing is quite specialised and requires lookups all over a single hard drive with many simultaneous look ups and that is where one single mechanical drive starts to show its limitations.

So as long as you are not battering your hard drive with a ton of requests a second, one mechanical hard drive is fine.

 

[opethdisciple]

How much ram do you have? I think for running VM's ram is just as important as hdd read/write speeds & cpu.

 

[JonJ678]

An old mechanical drive is usually still fine. Modern operating systems do a good job of caching likely-to-be-needed data in ram. Multiple virtual machines is a slightly unusual use case that can hammer the I/O system, depending on what the virtual machines are doing.

A normal box or workstation - it's only one OS hitting the drives. Running n virtual machines, you've got n+1 hitting the same drive. So SSDs look attractive.

It's interesting that your performance went down so much. Read speeds should be good on the raid 5 but write poor.

 

[Mr-White]

I guess the question is, how do others cope??

I got my first SSD 2.5 years ago and haven't looked back.

A one mechanical disk computer is considered budget these days.

MW

 

[zakblood]

i only this year went onto sdd's, spent the last number of years using some raptors, and never saw the need for anything faster.

before that i used Adaptec scsi cards and drives, all from ex work machines / servers etc, all low capacity but very high speeds, served me well for more years that i care to remember, wasn't even going to replace them as they still worked fine, just needed more space so went and got some raptors and never looked back, there still in a box today, more than 8 years old now and still going strong, not too sure i'll be saying the same about me newer sdd drives either, yes a lot faster, but only time will tell if they last as long.

with a good raid card, hdd can still be useful, but for me i like plenty of ram and use ram drives now for most high end stuff

 

[Armageus]

Multiple virtual machines is a slightly unusual use case that can hammer the I/O system, depending on what the virtual machines are doing.

You wouldn't run multiple physical machines on a single shared disk, so why would you assume multiple virtual machines would be any different.

A single drive will get hammered when seeking for multiple VMs - a modern SSD or even your legacy raid card can sustain a lot more IOPS than your single drive.

 

[El Pew]

You wouldn't run multiple physical machines on a single shared disk, so why would you assume multiple virtual machines would be any different.

Uh, nobody with any substantial virtual environment uses multiple hard disks with dedicated ones for each VM. One of the main purposes of virtualisation is to allow resources, included HDDs, to be shared. You don't think someone with a VDI environment consisting of hundreds of virtual desktops has dedicated drives for each, do you?

In fact, one of the main benefits of virtualisation is that you can use a shared disk and do a form of de-duplication. If you have 100 VMs with Win7 on them, there's no point wasting disk space keeping 100 copies of the Windows system files and all your applications if you can have a master image that all 100 machines are based on.

 

[Armageus]

Uh, nobody with any substantial virtual environment uses multiple hard disks with dedicated ones for each VM.

Nobody with any substantial virtual environment uses single physical drives to run multiple virtual machines either... not sure of your point. Most substantial virtual environments use SANs.

One of the main purposes of virtualisation is to allow resources, included HDDs, to be shared.

Generally resources that are worth sharing - e.g. SANS, Raid Arrays, Expensive SSDs... not single mechanical drives.

You don't think someone with a VDI environment consisting of hundreds of virtual desktops has dedicated drives for each, do you?

Nope, I assume they run them from a SAN or at the very least a RAID array - booting 100 virtual desktops from a single mechanical drive not going to happen.

In fact, one of the main benefits of virtualisation is that you can use a shared disk and do a form of de-duplication. If you have 100 VMs with Win7 on them, there's no point wasting disk space keeping 100 copies of the Windows system files and all your applications if you can have a master image that all 100 machines are based on.

Agreed there is no point wasting space - but again deduplication tends to only be available on RAID/SAN devices

 

[kedge]

games took an age to load, just a frustrating laggy experience.

This can be the same on ssd's, i personally don't find ssd's that much faster than a traditional mechanical hdd in general use or gaming if i'm honest, in fact one of my next purchases will be a sata 2 7200 hdd, i'll probably use the ssd for windows alone.

 

[ubersonic]

Nope, I assume they run them from a SAN or at the very least a RAID array

This.

 

[El Pew]

Nope, I assume they run them from a SAN or at the very least a RAID array - booting 100 virtual desktops from a single mechanical drive not going to happen.

Right, but equally there's no issue with running a small number of VMs off a single drive either. As we speak I have 4 VMs running off a 2.5" laptop drive with no worries, and that includes SQL, IIS, Exchange, and a bunch of other stuff.

A small business can quite comfortably run 10-20 VMs on an ESX or Hyper-V server from a fast SCSI drive or a small RAID array if they choose.