[Xen-devel] blkif shared ring

To:	xen-devel <xen-devel@xxxxxxxxxxxxxxxxxxx>
Subject:	[Xen-devel] blkif shared ring
From:	Samvel Yuri <samvelox@xxxxxxxxx>
Date:	Tue, 18 Nov 2008 15:29:48 -0800 (PST)
Delivery-date:	Tue, 18 Nov 2008 15:30:20 -0800
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Hello,

With xen 3.3.0 version, I understand that by increasing blkif_reqs you
possibly speed up writes by being able to write whole of tracks. And,
shared ring size is 64 between blkfront & blkback to fit in a page of
size PAGE_SIZE. Both blkfront & blkback accomodate shared ring within
a page size.

Wouldn't the shared ring be likely a bottleneck in very large number
os IOs, have anybody ran into such issue?

Is there a reason to _always_ accomodate ring buffer in a page? How
can I increase the shared ring size between blkfront & blkback?

Do you have any suggestions/recommendations?

thanks,
~Sam

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[Xen-devel] blkif shared ring