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From: Ivan Voras <ivoras@freebsd.org>
Date: Mon, 7 Feb 2011 11:37:43 +0100
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To: "Daniel O'Connor" <doconnor@gsoft.com.au>
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Subject: Re: Scheduler question
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On 07/02/2011 04:12, Daniel O'Connor wrote:
>
> On 07/02/2011, at 13:02, Ivan Voras wrote:
>>>> I'll be looking at it on Monday, I will let you know :)
>>>
>>> No luck with mlock() so it wouldn't appear to be paging is the issue :(
>>
>> I'm also interested in raw device vs file system access!
>
> Oops, sorry.. I just tried that now but it doesn't improve things :(

Meaning: you still get jitter?

> I am writing directly to /dev/ad10 but stressing /dev/ad14 (sudo tar -cf /dev/null /local0)

Can you do only one of those things? I.e. leave all the file systems
alone and just do something like 'diskinfo -vt /dev/ad14'?