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- Add Q3 report on ARM superpages

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Submitted by:	zbb
This commit is contained in:
Gabor Pali 2013-10-06 08:58:26 +00:00
parent 04e097f347
commit b96746dad2
Notes: svn2git 2020-12-08 03:00:23 +00:00 
svn path=/head/; revision=42864
1 changed files with 96 additions and 1 deletions

97
en_US.ISO8859-1/htdocs/news/status/report-2013-07-2013-09.xml
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@ -19,7 +19,7 @@
<!-- XXX: keep updating the number of entries -->
<p>Thanks to all the reporters for the excellent work! This report
contains 13 entries and we hope you enjoy reading it.</p>
contains 14 entries and we hope you enjoy reading it.</p>
<!-- XXX: set date for the next set of submissions -->
<p>The deadline for submissions covering between October and
@ -666,4 +666,99 @@
</ul>
</body>
</project>
<project cat='arch'>
<title>Superpages for ARMv7</title>
<contact>
<person>
<name>
<given>Zbigniew</given>
<common>Bodek</common>
</name>
<email>zbb@semihalf.com</email>
</person>
<person>
<name>
<given>Grzegorz</given>
<common>Bernacki</common>
</name>
<email>gjb@semihalf.com</email>
</person>
<person>
<name>
<given>Rafał</given>
<common>Jaworowski</common>
</name>
<email>raj@semihalf.com</email>
</person>
</contact>
<links>
<url href="http://static.usenix.org/events/osdi02/tech/full_papers/navarro/navarro.pdf" />
<url href="http://wiki.freebsd.org/ARMSuperpages" />
<url href="http://blogs.arm.com/software-enablement/1079-transparent-superpages-for-freebsd-on-arm" />
<url href="https://wiki.freebsd.org/201309DevSummit?action=AttachFile&amp;do=view&amp;target=semihalf-superpages_armv7.pdf" />
<url href="http://svnweb.freebsd.org/changeset/base/254918" />
</links>
<body>
<p>The ARM architecture is becoming more and more prevalent, with
increasing usage beyond the mobile and embedded space. Among the
more interesting industry trends emerging in the recent months,
there has been the concept of "ARM server". Some top-tier
companies, e.g. Dell and HP, have already started to develop
such systems.</p>
<p>Key to success of &os; in these new areas is dealing with the
sophisticated features of the platform, for example adding
support for superpages.</p>
<p>The objective of this project is to enable &os;/arm to utilize
superpages which would allow efficient use of TLB translations
(by enlarging TLB coverage), leading to improved performance in
many applications and scalability. This is intended to work on
ARMv7-based processors, however compatibility with ARMv6 will be
preserved.</p>
<p>The following steps have been made since the last status
report:</p>
<ul>
<li>The <tt>pmap</tt> module has been adjusted to fully utilize
superpages.</li>
<li>Found and fixed minor bugs in superpage management.</li>
<li>Implemented the <tt>pmap_advise()</tt> routine.</li>
<li>Performed extensive testing and benchmarking:
<ul>
<li>Giga Updates Per Second (GUPS) benchmark: 34% lower memory access
latency and 34% higher updates ratio.</li>
<li>LMbench: 38% lower memory latency.</li>
<li>Self-hosted <tt>buildworld</tt>: 20% shorter, using GCC.</li>
</ul></li>
<li>Final integration into &os; <tt>head</tt>.</li>
</ul>
<p>This project is jointly sponsored by The &os; Foundation and
Semihalf.</p>
</body>
<help>
<task>Adjust <tt>pmap</tt> to resolve the demotion issue caused by
the continuous active queue scanning in VM.</task>
<task>Support for 64KB page size.</task>
<task>Move <tt>pv_flags</tt> to page table entry descriptors.</task>
</help>
</project>
</report>