CentOS - Apr 2014 - write barrier support in CentOS 6

Hi,

I've been looking for an answer to this question and can't find anything
concrete that says full
support for write barriers has been backported to the stock kernel.

I've read that:

"There is incomplete write barrier support in kernel versions 2.6.32 and
earlier (2.6.31 has some
support, while 2.6.33 works for all types of device target) - RHEL 6 uses
2.6.32."

Now, I understand that Red Hat (and therefore CentOS) backport many upstream
features into the stock
kernel so how can I be sure that kernel 2.6.32-431.11.2.el6 has write barrier
support?

Any clues, anyone?

Kind regards,
Tom


-- 

Tom Robinson
IT Manager/System Administrator

MoTeC Pty Ltd

121 Merrindale Drive
Croydon South
3136 Victoria
Australia

T: +61 3 9761 5050
F: +61 3 9761 5051   
E: tom.robinson at motec.com.au

-------------- next part --------------
A non-text attachment was scrubbed...
Name: signature.asc
Type: application/pgp-signature
Size: 263 bytes
Desc: OpenPGP digital signature
URL:
<http://lists.centos.org/pipermail/centos/attachments/20140401/d630e9f2/attachment-0002.sig>

On 2014-04-01, Tom Robinson <tom.robinson at motec.com.au>
wrote:
> Now, I understand that Red Hat (and therefore CentOS) backport many
upstr> eam features into the stock
> kernel so how can I be sure that kernel 2.6.32-431.11.2.el6 has write
bar> rier support?
I believe you can look through the RHEL tech notes.  Here they are for
6.5:

https://access.redhat.com/site/documentation/en-US/Red_Hat_Enterprise_Linux/6/html-single/6.5_Technical_Notes/index.html

If you require barriers, you can always use the mainline kernel from
elrepo.  You can read about the mainline and long-term packages here:

http://elrepo.org/tiki/kernel-lt

You probably want the kernel-ml packages, but that page doesn't mention
the -lt packages.  Lots of CentOS admins use these kernels (including
me) and are happy with them.

--keith

-- 
kkeller at wombat.san-francisco.ca.us