https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=224479
--- Comment #16 from Mark Millard <mar...@dsl-only.net> --- (In reply to Konstantin Belousov from comment #14) You have written in the past that for file based (vnode-based) swap files the system is deadlock prone in a manor not under significant user control. >From what I've seen lots of folks set up the file based swap spaces without having a clue that such is the status. I was one of them at one time, following http://www.wonkity.com/~wblock/docs/html/ssd.html#_filesystems_and_trim material for SSDs that gave no hint of the issues involved. If the instructions had told me that I needed to enable the mode of use because of deadlock issues that do not happen with partition based swap spaces, I never would have tied it. I had swap space based deadlocks vastly faster than any sdcard wear out would have occurred: the configuration was simply unreliable over fairly short time frames. Also, the deadlocks are not examples of wear-and-tear. (You might want a better analogy for your point in that respect.) I view FreeBSD as designed to automatically avoid deadlocks for swapping only for partition-based swap spaces. Lesser points but more tied to this report: I was expecting that "shutdown -r now" might stop some processes before initiating the v-node removal, making such processes no longer sources of swap-in activity for later stages. (I was not thinking of any general fix to the deadlocking issues.) reboot, by contrast, I was expecting leaves more processes around that might try to swap-in in an untimely manor. I freely admit my expectations might be garbage-in/garbage-out. I was not expecting the sending of SIGSEGV or other signals to a process that is trying to swap-in after there is effectively nothing available to swap-in from. Does some involved kernel stack need to be in a swapped out state to have the problem that has been described? Or can it be a problem when no kernel stacks are swapped out? -- You are receiving this mail because: You are the assignee for the bug. _______________________________________________ freebsd-bugs@freebsd.org mailing list https://lists.freebsd.org/mailman/listinfo/freebsd-bugs To unsubscribe, send any mail to "freebsd-bugs-unsubscr...@freebsd.org"
