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Date: Sun, 19 Oct 2008 11:13:11 +0200
From: Avi Kivity <avi@redhat.com>
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Subject: Re: [Qemu-devel] [RFC] Disk integrity in QEMU
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Cc: Chris Wright <chrisw@redhat.com>, Mark McLoughlin <markmc@redhat.com>, kvm-devel <kvm-devel@lists.sourceforge.net>, Laurent Vivier <Laurent.Vivier@bull.net>, Ryan Harper <ryanh@us.ibm.com>, Paul Brook <paul@codesourcery.com>

Jens Axboe wrote:
>> IDE is limited to 256 sectors per transaction, or 128KB.  If a sync
>> transaction takes 5 ms, then your write rate is limited to 25 MB/sec. 
>> It's much worse if you're allocating qcow2 data, so each transaction is
>> several sync writes.
>>     
>
> No it isn't, even most IDE drives support lba48 which raises that limit
> to 64K sectors, or 32MB.
>   

Right, and qemu even supports this.  Thanks for the correction.

-- 
error compiling committee.c: too many arguments to function