Poor raid 1 performance?

To me, raid 1 seems the ideal solution. Raid 1 greatly improves data
security,

It improves safety. It does nothing at all for security.

He probably meant security in a broader sense. Like "it should be there,
where I have left it".

Yes, but also _any_ read is done twice, on both channels and both
mechanisms
(and furthermore they are then checked for equality between, which adds a
step, which could be a reason for misperformance).

I do not see why you could see improvements, any other things being equal
of
course.

http://www.9to5computer.com/atto/Com...igurations.htm
http://www.storagereview.com/guide20...gleLevel1.html

With a good controller, sequential read performance equals that of a single
drive, random read performance scales up with number of drives in a RAID.

Gerhard Fiedler wrote
Bruce T. Berger wrote

Is it possible to get improved read performance using raid 1??

No! Raid 1 exists solely for data preservation ...

Well, actually /my/ performance increased since I use RAID1 and don't
have to worry about the next disruptive hard drive crash anymore

Really, IMO there's little reason to run any computer that's used
to store critical data without RAID1 (or one of its derivatives).

Corse there is if the data activity isnt high and normal backup
will be completely adequate. Normal backup has a number of
advantages over any RAID, most obviously any stupidity or
infection doesnt get propagated to all copys virtually instantly.

Yes, you can certainly have both, but most
dont actually need the advantages of RAID.

Peter wrote

Why do you actually need improved read performance ?

He wants his computer to boot up faster

The obvious way to make it boot much faster again is
to minimise the number of boots and to hibernate instead
of shutdown when you do need to shut the system down.

and load games faster.

The obvious way to fix that problem is to keep
them loaded so they are an instant switch away.

To some people an extra 10-20 seconds is eternity.

Improved read performance isnt the only way to fix that. And
its perfectly possible to do much better than any RAID config
can do on that. Not a shred of rocket science required at all.

Peter wrote:

To me, raid 1 seems the ideal solution.
Raid 1 greatly improves data security,

It improves safety. It does nothing at all for security.

He probably meant security in a broader sense.
Like "it should be there, where I have left it".

But it doesnt help with real security, doing
something really stupid, or getting infected etc.

Peter wrote:

Well, actually /my/ performance increased since I use RAID1 and don't have
to worry about the next disruptive hard drive crash anymore

But it doesn't mean that you should do nothing when one drive fails.

But I can do nothing while it doesn't fail -- and that's most of the time


Really, IMO there's little reason to run any computer that's used to store
critical data without RAID1 (or one of its derivatives).

As little as a hundred bucks for a second disk and a new MB, if current does
not support RAID.

I didn't need a new MoBo. Just added a PCI RAID controller; seems to work
transparently. And that MoBo is pretty old. Are there really issues with
MoBos?

Gerhard

Well, actually /my/ performance increased since I use RAID1 and don't
have
to worry about the next disruptive hard drive crash anymore

But it doesn't mean that you should do nothing when one drive fails.

But I can do nothing while it doesn't fail -- and that's most of the time


That is what most of the people do. Even those with PCs with single drives.


Really, IMO there's little reason to run any computer that's used to
store
critical data without RAID1 (or one of its derivatives).

As little as a hundred bucks for a second disk and a new MB, if current
does
not support RAID.

I didn't need a new MoBo. Just added a PCI RAID controller; seems to work
transparently.

You can add RAID controller, sure.

And that MoBo is pretty old. Are there really issues with
MoBos?

Not less than with HaDrives

Rod Speed wrote:

Really, IMO there's little reason to run any computer that's used
to store critical data without RAID1 (or one of its derivatives).

Corse there is if the data activity isnt high and normal backup
will be completely adequate.

That's why I wrote "critical data". I consider the result of my work
"critical", as it is what I get paid for. If it takes me half a day to redo
the work of a day, and I do daily backups (both probably a common situation
for everybody who works with a computer), a RAID1 array is a quite nifty
thing, as it should give me approximately 0 downtime in case of a disk
problem. Otherwise, I could easily have a day downtime (need to get drive,
restore last image, redo all the work that happened afterwards). The only
computer-caused downtime I had so far was either a harddisk crash or a
Windows reinstall -- and RAID1 is supposed to crack down on the first
one. (I haven't had a crash since I installed my arrays...)

Normal backup has a number of advantages over any RAID,

RAID1 is no substitution for backup, of course, it's an enhancement for an
adequate backup strategy.

Yes, you can certainly have both, but most dont actually need the
advantages of RAID.

Most don't, but then most don't create critical data. I'd recommend it for
everybody who creates critical data.

Gerhard

Arno Wagner wrote:
Previously Mark wrote:

Hi there,


I am planning on building a new computer system. Given the current cheap
price and massive capacity of hard drives, I am thinking of using a raid
array.


To me, raid 1 seems the ideal solution. Raid 1 greatly improves data
security,


It improves safety. It does nothing at all for security.



Of course, if you look up security in the thesauraus, a synonym is
safety. I may not have used the correct technical term, but I think most
people who know English knew what I meant.

Rod Speed wrote:
Peter wrote


Why do you actually need improved read performance ?


He wants his computer to boot up faster


The obvious way to make it boot much faster again is
to minimise the number of boots and to hibernate instead
of shutdown when you do need to shut the system down.



My computer hasn't always recovered from hibernation okay, something to
do with the power management. Hence, I am hesitant to use it. Also, I do
like the idea of rebooting regularly to stop the system becoming bloated
with memory resident programs that I don't need.

and load games faster.


The obvious way to fix that problem is to keep
them loaded so they are an instant switch away.


Okay, you obviously don't play games. First, having them stay in the
background quite often reduces the computer to a crawl. Second, even if
you are in the game, level loads (and saving and loading your position)
can be very slow.


To some people an extra 10-20 seconds is eternity.


Improved read performance isnt the only way to fix that. And
its perfectly possible to do much better than any RAID config
can do on that. Not a shred of rocket science required at all.



I'd be interested in other techniques. What do you suggest?