Date: Wed, 20 Dec 2017 12:51:38 +0000 From: bugzilla-noreply@freebsd.org To: freebsd-bugs@FreeBSD.org Subject: [Bug 224479] kernel panic in reboot+swapoff sys call Message-ID: <bug-224479-8-UduZbC90V9@https.bugs.freebsd.org/bugzilla/> In-Reply-To: <bug-224479-8@https.bugs.freebsd.org/bugzilla/> References: <bug-224479-8@https.bugs.freebsd.org/bugzilla/>
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https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=3D224479 --- Comment #2 from Wolfram Schneider <wosch@FreeBSD.org> --- the suspect commit is: commit c123c7433b7eb3ccacfa1bae8ae136c61cfe8462 Author: alc <alc@FreeBSD.org> Date: Tue Nov 28 17:46:03 2017 +0000 When the swap pager allocates space on disk, it requests contiguous blocks in a single call to blist_alloc(). However, when it frees that space, it previously called blist_free() on each block, one at a time. With this change, the swap pager identifies ranges of contiguous blocks to be freed, and calls blist_free() once per range. In one extreme case, that is described in the review, the time to perform an munmap(2) was reduced by 55%. Submitted by: Doug Moore <dougm@rice.edu> Reviewed by: kib MFC after: 1 week Differential Revision: https://reviews.freebsd.org/D12397 I did a git revert, recompiled the kernel and the problem was gone. Note: I do not say this commit created a new bug. It is very likely that it triggered an old bug. There are many reports about this kind of bug for old= er releases on the net. --=20 You are receiving this mail because: You are the assignee for the bug.=
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