linux-kernel - Re: [Xen-devel] Backport request to stable of two performance related fixes for xen-blkfront (3.13 fixes to earlier trees)

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <87lhtwznhl.fsf@vitty.brq.redhat.com>
Date:	Tue, 20 May 2014 13:41:10 +0200
From:	Vitaly Kuznetsov <vkuznets@...hat.com>
To:	Roger Pau Monné <roger.pau@...rix.com>
Cc:	Konrad Rzeszutek Wilk <konrad.wilk@...cle.com>, axboe@...nel.dk,
	felipe.franciosi@...rix.com, gregkh@...uxfoundation.org,
	linux-kernel@...r.kernel.org, stable@...r.kernel.org,
	jerry.snitselaar@...cle.com, xen-devel@...ts.xenproject.org
Subject: Re: [Xen-devel] Backport request to stable of two performance related fixes for xen-blkfront (3.13 fixes to earlier trees)

Roger Pau Monné <roger.pau@...rix.com> writes:

> On 20/05/14 11:54, Vitaly Kuznetsov wrote:
>> Vitaly Kuznetsov <vkuznets@...hat.com> writes:
>> 
>>> 1) ramdisks (/dev/ram*) (persistent grants and indirect descriptors
>>> disabled)
>> 
>> sorry, there was a typo. persistent grants and indirect descriptors are
>> enabled with ramdisks, otherwise such testing won't make any sense.
>
> I'm not sure how is that possible, from your description I get that you
> are using 3.11 on the Dom0, which means blkback has support for
> persistent grants and indirect descriptors, but the guest is RHEL7,
> that's using the 3.10 kernel AFAICT, and this kernel only has persistent
> grants implemented.

RHEL7 kernel is mostly merged with 3.11 in its Xen part, we have
indirect descriptors backported.

Actually I tried my tests with upstream (Fedora) kernel and results were
similar. I can try comparing e.g. 3.11.10 with 3.12.0 and provide exact
measurements.

-- 
  Vitaly
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/