linux-kernel - Re: [PATCH v1 7/7] xen-block: implement indirect descriptors

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 for Android: free password hash cracker in your pocket

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

Message-ID: <516ED633.3040205@citrix.com>
Date:	Wed, 17 Apr 2013 19:04:51 +0200
From:	Roger Pau Monné <roger.pau@...rix.com>
To:	Konrad Rzeszutek Wilk <konrad.wilk@...cle.com>
CC:	"linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>,
	"xen-devel@...ts.xen.org" <xen-devel@...ts.xen.org>
Subject: Re: [PATCH v1 7/7] xen-block: implement indirect descriptors

On 17/04/13 16:25, Konrad Rzeszutek Wilk wrote:
>>> Perhaps the xen-blkfront part of the patch should be just split out to make
>>> this easier?
>>>
>>> Perhaps what we really should have is just the 'max' value of megabytes
>>> we want to handle on the ring.
>>>
>>> As right now 32 ring requests * 32 segments = 4MB.  But if the user wants
>>> to se the max: 32 * 4096 = so 512MB (right? each request would handle now 16MB
>>> and since we have 32 of them = 512MB).
>>
>> I've just set that to something that brings a performance benefit
>> without having to map an insane number of persistent grants in blkback.
>>
>> Yes, the values are correct, but the device request queue (rq) is only
>> able to provide read requests with 64 segments or write requests with
>> 128 segments. I haven't been able to get larger requests, even when
>> setting this to 512 or higer.
> 
> What are you using to drive the requests? 'fio'?

Yes, I've tried fio with several "bs=" values, but it doesn't seem to
change the size of the underlying requests. Have you been able to get
bigger requests?
--
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/