Richard L. Hamilton wrote: >>>> BTW: Does Solaris/x86 support something like >> marking certain pages as >>>> non-cacheable (for example in some cases it may >> be nice to turn caching >>>> off if the traffic caused by cache coherency (or >> even the plain usage of >>>> cache lines for data which are only read or >> written once) causes more >>>> trouble than just turning the cache off for such >> data) ? >>> Yes, see >>> >> http://src.opensolaris.org/source/xref/onnv/onnv-gate/ >> usr/src/uts/common/vm/page.h#485 >> >> Is this somehow accessible from userland applications >> ? > > If there were (or were to be), surely that would be madvise(3c) > and ultimately memcntl(2), right? Do MADV_ACCESS_LWP vs > MADV_ACCESS_MANY affect this indirectly if not altogether predictably?
AFAIK, MADV_ACCESS_* affects how memory will be distributed across nodes, so yes, it affects indirectly. But nothing related to not using cache. There is MADV_FREE, which advices the kernel that a given area can be freed. Take a look at the man entry for madvise(3). But overall, I don't recall seeing any userland way of turning cache off.. -- Rafael Vanoni [EMAIL PROTECTED] http://blogs.sun.com/rv _______________________________________________ perf-discuss mailing list perf-discuss@opensolaris.org
