Dear Karel,
Thanks - wait - this post from 2006 you mentioned now, is it saying that
actually >32bit/>~3GB buffer cache IS SUPPORTED/WORKS on any AMD64 *with
IOMMU* support in the CPU, and was working all the time??
(That would mean that I misunderstood those references I posted in the
previous email because in actuality the 32bit/~3GB constraint only is in
certain usecases that is on non-IOMMU CPU:s.)
Please clarify!
So if so, any Intel processor with the "Intel® Virtualization Technology
for Directed I/O (VT-d)" feature such as for example this one
http://ark.intel.com/products/81061/ , or any of the CPU:s listed on
https://en.wikipedia.org/wiki/List_of_IOMMU-supporting_hardware , has
that support?
Does the motherboard need specific support too as Wikipedia indicates -
though at least any Xeon server motherboard from the last 3-4 years must
for sure have it right?
Thank you everyone for your excellent work with OpenBSD!
Best regards,
Tinker
[1]
David Mazieres linked to two docs in there, those are only on
archive.org now:
https://web.archive.org/web/20150814051509/http://www.intel.com/content/dam/www/public/us/en/documents/product-specifications/vt-directed-io-spec.pdf
https://web.archive.org/web/20081218031805/http://www.amd.com/us-en/assets/content_type/white_papers_and_tech_docs/34434.pdf
On 2016-02-14 01:15, Karel Gardas wrote:
I think you would also like to investigate this one:
http://www.undeadly.org/cgi?action=article&sid=20060614160000
Some quite deep reading [1] taught me that at least quite recently,
there
was a ~3GB cap on the buffer cache, independent of architecture and
system
RAM size.
