Re: [squid-users] squid with linux or freeBSD?

----- Original Message -----
From: "Brett Lymn" <blymn@baesystems.com.au>
To: "fooler" <fooler@skyinet.net>
Cc: "Brett Lymn" <blymn@baesystems.com.au>; "Colin Campbell"
<sgcccdc@citec.qld.gov.au>; <squid-users@squid-cache.org>
Sent: Thursday, May 01, 2003 2:04 PM
Subject: Re: [squid-users] squid with linux or freeBSD?

> On Thu, May 01, 2003 at 01:40:44PM +0800, fooler wrote:
> >
> > but it is much also posible to implement that kind of technique as what
i
> > describe above when two disks left for maximum performance right?
>
> No. RAID 5 distributes the parity across all the disks to prevent the
> parity disk becoming overloaded with transactions (as happens with
> RAID 3).

hmmm... im not really satisfied with your answers to my questions and please
dont excuse that i dont understand how raid level works...

> In a 3 disk raid 5 stripe if a disk fails then you will lose
> one third of your parity bits (but the other disks have the data) and
> one third of your data bits (but the data can be reconstructed using
> the parity)

no.. not necessarily 1/3 of your parity bits... it really depends how many
stripes per disk you have... for example...

  D1 D2 D3
+---+ +---+ +---+
| P | | | | |
+---+ +---+ +---+
| | | P | | |
+---+ +---+ +---+
| | | | | P |
+---+ +---+ +---+
| P | | | | |
+---+ +---+ +---+

the above has 3 disks with 4 stripes per disk.... if disk 1 (D1) is failed,
you lost 2/4 of your parity blocks and 1/4 for disk 2 and 3 respectively...

anyway.. this is already out of topic for squid mailing list.. thanks for
your time spending with me...

fooler.
Received on Thu May 01 2003 - 01:11:29 MDT