RAID 0 is usually a foolish choice for desktops

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Archived from groups: alt.comp.periphs.mainboard.asus (More info?)

In article <Na4Gc.193628$Gx4.142602@bgtnsc04-news.ops.worldnet.att.net>,
ron-reaugh@worldnet.att.net says...
>
> "Leythos" <void@nowhere.com> wrote in message
> news:MPG.1b528c1ef34106a298a755@news-server.columbus.rr.com...
> > In article <Xo1Gc.60325$OB3.45145@bgtnsc05-news.ops.worldnet.att.net>,
> > ron-reaugh@worldnet.att.net says...
> > > In fact usually a stripe size of
> > > 16K or 32k for two drives is usually optimal. Also Anand doesn't seem
> to
> > > understand the definition of what a stripe is.
> >
> > Stripe size is optimal based on the type of data being accessed, which,
> > as most people tend to overgeneralise, is different based on what the
> > primary function is for the system.
> >
> > As an example:
> >
> > 1) Database - larger stripes are better
>
> Wrong. Stripe units 2x-3x the average record size is optimal.
>
> > 2) Large images or other LARGE files - larger is better
>
> Wrong, The stripe size that optimizes sustained transfer rate is best here
> and often that's NOT large stripe size.
>
> > 3) Most home (non-soho/non business) systems - smaller
> > 4) Video editing - larger
>
> No.
>
> > 5) Web Page Design - smaller
> > 6) Games - smaller
> >
> > And the list goes on.
>
> And you make these up how?

I'm not sure how to reply to you without ticking you off, but you are
wrong, larger average file sizes means larger stripe sizes for better
performance, which is exactly what I wrote.

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Archived from groups: alt.comp.periphs.mainboard.asus (More info?)

In article <YB4Gc.7399$WM5.337595@news20.bellglobal.com>,
triffid@nebula.net says...
> For the life of me, I cannot understand how RAID0 can claim to be RAID
> at all.

It does not mean data-redundancy, it means more than one drive doing the
job of one drive.

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Archived from groups: alt.comp.periphs.mainboard.asus (More info?)

"Leythos" <void@nowhere.com> wrote in message
news:MPG.1b5331506678f48498a758@news-server.columbus.rr.com...
> In article <Na4Gc.193628$Gx4.142602@bgtnsc04-news.ops.worldnet.att.net>,
> ron-reaugh@worldnet.att.net says...
> >
> > "Leythos" <void@nowhere.com> wrote in message
> > news:MPG.1b528c1ef34106a298a755@news-server.columbus.rr.com...
> > > In article <Xo1Gc.60325$OB3.45145@bgtnsc05-news.ops.worldnet.att.net>,
> > > ron-reaugh@worldnet.att.net says...
> > > > In fact usually a stripe size of
> > > > 16K or 32k for two drives is usually optimal. Also Anand doesn't
seem
> > to
> > > > understand the definition of what a stripe is.
> > >
> > > Stripe size is optimal based on the type of data being accessed,
which,
> > > as most people tend to overgeneralise, is different based on what the
> > > primary function is for the system.
> > >
> > > As an example:
> > >
> > > 1) Database - larger stripes are better
> >
> > Wrong. Stripe units 2x-3x the average record size is optimal.
> >
> > > 2) Large images or other LARGE files - larger is better
> >
> > Wrong, The stripe size that optimizes sustained transfer rate is best
here
> > and often that's NOT large stripe size.
> >
> > > 3) Most home (non-soho/non business) systems - smaller
> > > 4) Video editing - larger
> >
> > No.
> >
> > > 5) Web Page Design - smaller
> > > 6) Games - smaller
> > >
> > > And the list goes on.
> >
> > And you make these up how?
>
> I'm not sure how to reply to you without ticking you off, but you are
> wrong, larger average file sizes means larger stripe sizes for better
> performance, which is exactly what I wrote.

Utter nonsense. There is NO first order relation between file size and
stripe size.
 
Archived from groups: alt.comp.periphs.mainboard.asus (More info?)

In article <0IhGc.197449$Gx4.171408@bgtnsc04-news.ops.worldnet.att.net>,
ron-reaugh@worldnet.att.net says...
> > I'm not sure how to reply to you without ticking you off, but you are
> > wrong, larger average file sizes means larger stripe sizes for better
> > performance, which is exactly what I wrote.
>
> Utter nonsense. There is NO first order relation between file size and
> stripe size.

You are correct, there is no relation between file size and stripe size,
but there is a relation between file size, stripe size and performance.

Envision stripe size like you would cluster size and then you'll
understand.

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Archived from groups: alt.comp.periphs.mainboard.asus (More info?)

"Leythos" <void@nowhere.com> wrote in message
news:MPG.1b5389ad5271855f98a75c@news-server.columbus.rr.com...
> In article <0IhGc.197449$Gx4.171408@bgtnsc04-news.ops.worldnet.att.net>,
> ron-reaugh@worldnet.att.net says...
> > > I'm not sure how to reply to you without ticking you off, but you are
> > > wrong, larger average file sizes means larger stripe sizes for better
> > > performance, which is exactly what I wrote.
> >
> > Utter nonsense. There is NO first order relation between file size and
> > stripe size.
>
> You are correct, there is no relation between file size and stripe size,
> but there is a relation between file size, stripe size and performance.
>
> Envision stripe size like you would cluster size and then you'll
> understand.


You are simply WRONG. The concept of cluster size and stripe size have no
relation to one another. Cluster is a logical software concept of disk
storage allocation. Stripe size has to do with physical allocation across
drives.

Envision the difference between stripe size and stripe unit size. Stripe
size has nothing to do with performance but stripe unit size often does.
The optimal stripe unit size for streaming/large-file performance is one
that quickly starts and then maintains the continuous stream of data on all
the drives in a RAID 0 set. The goal is not to lose any revolutions. If
the stripe unit size is too large then the initial OS read request may not
be large enough to get all the HDs in the RAID 0 set starting a read. If
the stripe unit size is too large then the drive's read ahead may not be
sufficient to continue the stream until the next read request arrives. Fail
these criteria and you lose revolutions and therfore non-optimal streaming
performance. Stick to an area where you have some actual knowledge.

Large stripes are non-optimal for streaming. There's a middle ground that's
usually optimal and that depends on controller HW design, RAID drivers
design, OS design and the HD's internal caching and other behaviors and
settings.
 
Archived from groups: alt.comp.periphs.mainboard.asus (More info?)

In article <iwjGc.63250$OB3.27883@bgtnsc05-news.ops.worldnet.att.net>,
ron-reaugh@worldnet.att.net says...
> Cluster is a logical software concept of disk
> storage allocation. Stripe size has to do with physical allocation across
> drives.

Yep, I agree and we're not going to agree on it. It could be that we're
thinking the same thing and just not able to put it into type, but I'll
bow out of this thread with what I believe.

There are two things that I know about Stripes:

1) Number of drives in the stripe set has an impact on performance.
2) Size of the stripe on each drive also impacts performance.

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Archived from groups: alt.comp.periphs.mainboard.asus (More info?)

SCSI can be cheaper.

An ultra 320 raid controller costs big time. A top end 8 drive SATA raid
controller will cost about the same per disc.

73 GB SCSI drives are (here) cheaper than the raptors and have comparable
stats (the raptors come out very well in many benchmarks). So with 14 drives
on one RAID controller (you never should as this exceeds the IO performance
of the controller by a long way) you have one nice clear solution especially
if it is dual channel. I have been playing with an Intel controller recently
(ex LSI or something) and it has all the bells and whistles... yum.

Needless to say, the raptors will come down in price a little faster than
the SCSI, and a new drive design or two is no doubt already in the wings. So
things are improving! Gone are the days of 5, 10, 20 MBs and other slow
SCSI, the old yich clunkity clunk IDE drives. Thank goodness. Now we have
IDE drives with 1 year warrantee. That sends a shiver down my spine - if the
drive doesn't have a 3 year warrantee then its no good.

- Tim




"Winey" <NOSPAMME@no-one-here.com> wrote in message
news:v9ebe01c582mi333rjhtrflplolt0at7s1@4ax.com...
> On Fri, 2 Jul 2004 22:46:34 +1200, "Tim" <Tim@NoSpam.com> wrote:
>
>>Agree 100%. It's a good article. SCSI is still smoother esp with a dual
>>CPU
>>system. Perhaps the NCQ drives will help iron things out, then dual core
>>opterons will bring a smile to everones faces.
>
> What are NCQ drives?
>
> Glad you still like SCSI. If you look at the pricing for some of
> the high-perf 73 GB ATA drives, you're going to pay about what the
> same drives cost in SCSI-land.
>
> --W--
>
>>
>>- Tim
>>
>>"Milleron" <millerdot90@SPAMlessosu.edu> wrote in message
>>news:4689e01rsqu2l89n2of9ehcurvldhg69od@4ax.com...
>>> If more proof of this old contention is needed, there's a cutting-edge
>>> review by Anand Shimpi on AnandTech.com:
>>> http://www.anandtech.com/storage/showdoc.html?i=2101
>>>
>>> As always in these tests, the real-world improvement achieved with
>>> RAID 0 varies between 0 and 4%, which is simply imperceptible. The
>>> price that's paid is two-fold: (1) the difference between the RAID
>>> and a single drive of the same capacity, and (2) the DOUBLING of the
>>> chance of a hard-drive failure.
>>>
>>> For the life of me, I can't understand why so many users decide to
>>> install RAID 0 on desktops.
>>>
>>> RAID 1 is another matter entirely, but, as Anand says, "If you haven't
>>> gotten the hint by now, we'll spell it out for you: there is no place,
>>> and no need for a RAID-0 array on a desktop computer. The real world
>>> performance increases are negligible at best and the reduction in
>>> reliability, thanks to a halving of the mean time between failure,
>>> makes RAID-0 far from worth it on the desktop."
>>>
>>>
>>> Ron
>>
>
 
Archived from groups: alt.comp.periphs.mainboard.asus (More info?)

"Tim" <Tim@NoSpam.com> wrote in message news:ccb6um$ni0$1@lust.ihug.co.nz...
> SCSI can be cheaper.
>
> An ultra 320 raid controller costs big time. A top end 8 drive SATA raid
> controller will cost about the same per disc.
>
> 73 GB SCSI drives are (here) cheaper than the raptors and have comparable
> stats (the raptors come out very well in many benchmarks).

No, comparable SCSI HDs are NOT cheaper.

>So with 14 drives
> on one RAID controller (you never should as this exceeds the IO
performance
> of the controller by a long way) you have one nice clear solution
especially
> if it is dual channel. I have been playing with an Intel controller
recently
> (ex LSI or something) and it has all the bells and whistles... yum.
>
> Needless to say, the raptors will come down in price a little faster than
> the SCSI, and a new drive design or two is no doubt already in the wings.
So
> things are improving! Gone are the days of 5, 10, 20 MBs and other slow
> SCSI, the old yich clunkity clunk IDE drives. Thank goodness. Now we have
> IDE drives with 1 year warrantee. That sends a shiver down my spine - if
the
> drive doesn't have a 3 year warrantee then its no good.

Nonsense. The warranty length is simply a price point decision and say
nothing about reliability. Many ATA HDs have 3 year warranties.
 
Archived from groups: alt.comp.periphs.mainboard.asus (More info?)

"Leythos" <void@nowhere.com> wrote in message
news:MPG.1b539033c0367a3598a75d@news-server.columbus.rr.com...
> In article <iwjGc.63250$OB3.27883@bgtnsc05-news.ops.worldnet.att.net>,
> ron-reaugh@worldnet.att.net says...
> > Cluster is a logical software concept of disk
> > storage allocation. Stripe size has to do with physical allocation
across
> > drives.
>
> Yep, I agree and we're not going to agree on it. It could be that we're
> thinking the same thing and just not able to put it into type, but I'll
> bow out of this thread with what I believe.
>
> There are two things that I know about Stripes:
>
> 1) Number of drives in the stripe set has an impact on performance.

Yep. more means faster streaming.

> 2) Size of the stripe on each drive also impacts performance.

That's called the 'stripe unit' size and does affect performance. Not too
big and not too small is generally optimal for streaming.
 
Archived from groups: alt.comp.periphs.mainboard.asus (More info?)

In article <FgkGc.198252$Gx4.43816@bgtnsc04-news.ops.worldnet.att.net>,
ron-reaugh@worldnet.att.net says...
>
> "Leythos" <void@nowhere.com> wrote in message
> news:MPG.1b539033c0367a3598a75d@news-server.columbus.rr.com...
> > In article <iwjGc.63250$OB3.27883@bgtnsc05-news.ops.worldnet.att.net>,
> > ron-reaugh@worldnet.att.net says...
> > > Cluster is a logical software concept of disk
> > > storage allocation. Stripe size has to do with physical allocation
> across
> > > drives.
> >
> > Yep, I agree and we're not going to agree on it. It could be that we're
> > thinking the same thing and just not able to put it into type, but I'll
> > bow out of this thread with what I believe.
> >
> > There are two things that I know about Stripes:
> >
> > 1) Number of drives in the stripe set has an impact on performance.
>
> Yep. more means faster streaming.
>
> > 2) Size of the stripe on each drive also impacts performance.
>
> That's called the 'stripe unit' size and does affect performance. Not too
> big and not too small is generally optimal for streaming.

See, we were on the same page, I just wasn't using the proper terms for
it. I also was not talking about streaming and more thinking of
performance for specific types of files.

--
--
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(Remove 999 to reply to me)
 
Archived from groups: alt.comp.periphs.mainboard.asus (More info?)

"Leythos" <void@nowhere.com> wrote in message
news:MPG.1b539fa2fc1526f498a75e@news-server.columbus.rr.com...
> In article <FgkGc.198252$Gx4.43816@bgtnsc04-news.ops.worldnet.att.net>,
> ron-reaugh@worldnet.att.net says...
> >
> > "Leythos" <void@nowhere.com> wrote in message
> > news:MPG.1b539033c0367a3598a75d@news-server.columbus.rr.com...
> > > In article <iwjGc.63250$OB3.27883@bgtnsc05-news.ops.worldnet.att.net>,
> > > ron-reaugh@worldnet.att.net says...
> > > > Cluster is a logical software concept of disk
> > > > storage allocation. Stripe size has to do with physical allocation
> > across
> > > > drives.
> > >
> > > Yep, I agree and we're not going to agree on it. It could be that
we're
> > > thinking the same thing and just not able to put it into type, but
I'll
> > > bow out of this thread with what I believe.
> > >
> > > There are two things that I know about Stripes:
> > >
> > > 1) Number of drives in the stripe set has an impact on performance.
> >
> > Yep. more means faster streaming.
> >
> > > 2) Size of the stripe on each drive also impacts performance.
> >
> > That's called the 'stripe unit' size and does affect performance. Not
too
> > big and not too small is generally optimal for streaming.
>
> See, we were on the same page, I just wasn't using the proper terms for
> it. I also was not talking about streaming and more thinking of
> performance for specific types of files.

Big files and streaming is the same thing. A big file for this purpose is
one whose size is greater than the stripe size.

Multithreaded/multitasked small record random I/O is optimal performance
wise when the stripe unit is about 3x the average record size.
 
Archived from groups: alt.comp.periphs.mainboard.asus (More info?)

"Tim" <Tim@NoSpam.com> wrote in message news:cccltb$nrt$1@lust.ihug.co.nz...
> Ron,
>
> Shop around - the prices are near identical (raptor vs. 10kRPM SCSI).

I did that just recently. 73GB Raptors are about $190 and the Atlas 10K IV
is about $300.
 
Archived from groups: alt.comp.periphs.mainboard.asus (More info?)

On Sun, 04 Jul 2004 03:18:41 GMT, Barry Watzman
<WatzmanNOSPAM@neo.rr.com> wrote:

>An interesing comment, the author notes that:
>
>"The price that's paid is two-fold: (1) the difference between the RAID
>and a single drive of the same capacity"
>
>I detect a presumption that RAID is more expensive. In fact, it's often
>LESS expensive. I've bought Western Digital 1200JB's (7200rpm, 8 meg
>cache) for as low as $59. You cannot buy a 240 gig drive for $118.
>
>
>

I got a wd250 Gig for $129 after rebate,

Picked one up for $139 with no rebate.

Shop til you drop 😉
 
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