× The internal search function is temporarily non-functional. The current search engine is no longer viable and we are researching alternatives.
As a stop gap measure, we are using Google's custom search engine service.
If you know of an easy to use, open source, search engine ... please contact support@midrange.com.



Hi Larry

Thanks for taking the trouble to reply.

I'd be interested to see what Sue comes up with but you've confirmed what
I'm thinking so I'll just go with that.

On Thu, Oct 16, 2014 at 1:32 PM, DrFranken <midrange@xxxxxxxxxxxx> wrote:

Mirror will nearly always outperform RAID.
Mirror is always two writes for a write, one read (with two choices) for a
read.
RAID 5 is two reads and two writes for a write, one read (with one choice)
for a read.

SSDs are so fast you can do mirroring on some of the lower cost
controllers with NO Cache. In fact some are SSD only.

I can't put my finger on it just now but Sue Baker has frequently
indicated Mirror over RAID as well for SSDs.

- Larry "DrFranken" Bolhuis

www.frankeni.com
www.iDevCloud.com
www.iInTheCloud.com

On 10/15/2014 7:53 PM, Evan Harris wrote:

Hi Larry

that's what I have done in the past and that is my preference. Is there an
IBM best practise recommendation I can refer to or do that you know of or
do you have some logic as to why (like, because they are SSD's)

I'm guessing you have something due to the quick answer.. :)

On Thu, Oct 16, 2014 at 12:29 PM, DrFranken <midrange@xxxxxxxxxxxx>
wrote:

Mirror. Done.


- Larry "DrFranken" Bolhuis

www.frankeni.com
www.iDevCloud.com
www.iInTheCloud.com


On 10/15/2014 7:01 PM, Evan Harris wrote:

Hi all


I have a customer who has a ordered a system with 4 x 387Gb SSDs in the
CEC
and 24 x 283Gb disks housed in a 5887.

With respect to the SSDs, what is the better approach - Mirroring or
RAID
? The system is not pushed for space so mirroring is an option if there
is
a reason for doing that, otherwise either approach works fine for this
install.

I normally prefer to hot spare RAID sets these days and I guess I could
do
a 3 disk RAID set and hot spare it (not my preference...) but in that
case
it seems to me MIrroring would probably be a better approach.

Any opinions as to which approach is better ?


--

This is the Midrange Systems Technical Discussion (MIDRANGE-L) mailing
list
To post a message email: MIDRANGE-L@xxxxxxxxxxxx
To subscribe, unsubscribe, or change list options,
visit: http://lists.midrange.com/mailman/listinfo/midrange-l
or email: MIDRANGE-L-request@xxxxxxxxxxxx
Before posting, please take a moment to review the archives
at http://archive.midrange.com/midrange-l.




--
This is the Midrange Systems Technical Discussion (MIDRANGE-L) mailing list
To post a message email: MIDRANGE-L@xxxxxxxxxxxx
To subscribe, unsubscribe, or change list options,
visit: http://lists.midrange.com/mailman/listinfo/midrange-l
or email: MIDRANGE-L-request@xxxxxxxxxxxx
Before posting, please take a moment to review the archives
at http://archive.midrange.com/midrange-l.





As an Amazon Associate we earn from qualifying purchases.

This thread ...

Replies:

Follow On AppleNews
Return to Archive home page | Return to MIDRANGE.COM home page

This mailing list archive is Copyright 1997-2024 by midrange.com and David Gibbs as a compilation work. Use of the archive is restricted to research of a business or technical nature. Any other uses are prohibited. Full details are available on our policy page. If you have questions about this, please contact [javascript protected email address].

Operating expenses for this site are earned using the Amazon Associate program and Google Adsense.