Ivan wrote:
Is there any documentation available about the Page Replacement Algorithm used
in Solaris?
Page scanner, or page cache?
The Solaris Internals book (www.solarisinternals.com) is a good place to
start for the current stuff. Solaris is (still) using the two-handed clock
algorithm for page scanning described in the UNIX texts like Vahalia --
when I went digging through the SCCS history the original commit of this
file was by none other than Bill Joy himself. It's old, and if you've
looked at the internals of the other open source OSes out there, you
realize it's quite obsolete. We're in the middle of writing a better page
scanner right now, in fact, and it will be showing up in Nevada hopefully
in about six months; I don't have any writeup on the design yet but
hopefully there will be one coming soon.
As far as the page cache goes, the cyclic cache currently in Solaris is
the one Richard McDougall designed in 2.6/7, and as such is described
well in his book, and in his blog (blogs.sun.com/rmc). We're also in the
middle of putting shape charges on that code as well, to replace it with
something more like the Adaptive Replacement Cache which can handle
frequency as well as recency. Unlike the current page cache the new page
cache will also be set up to handle large pages so that MPSS can truly be
made universal.
Those of us working in the VM system have been a little too busy hacking
away lately and not busy enough with documentation and setting up the
community pages, but that will change soon when our big project makes it
to beta. Keep an eye out for it.
- Eric
_______________________________________________
opensolaris-code mailing list
[email protected]
http://mail.opensolaris.org/mailman/listinfo/opensolaris-code
