Date: Fri, 11 Jan 2019 18:17:27 +0000 From: bugzilla-noreply@freebsd.org To: emulation@FreeBSD.org Subject: [Bug 230160] linuxulator doesn't implement madvise(MADV_DONTNEED) and any MADV_ flags with values >= 8 correctly Message-ID: <bug-230160-4077-FJyTssDZsA@https.bugs.freebsd.org/bugzilla/> In-Reply-To: <bug-230160-4077@https.bugs.freebsd.org/bugzilla/> References: <bug-230160-4077@https.bugs.freebsd.org/bugzilla/>
next in thread | previous in thread | raw e-mail | index | archive | help
https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=3D230160 --- Comment #8 from David Chisnall <theraven@FreeBSD.org> --- (In reply to Bill Sorenson from comment #7) As I said above, there is no mechanism for doing this with shared memory segments - we cannot zero pages in the middle of a shared-memory segment without using memset / bzero and this does not allow the kernel to decommit= the physical pages. I haven't tested whether MAV_FREE allows the kernel to laz= ily replace the pages with zeroed pages, but for our uses we need to guarantee zeroing. On Linux you can do this with some forms of shared memory using fallocate to punch a hole in the underlying object, though apparently it isn't very reliable. --=20 You are receiving this mail because: You are the assignee for the bug.=
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?bug-230160-4077-FJyTssDZsA>