Date: Mon, 25 Jul 2016 23:30:09 -0700 From: Mark Millard <markmi@dsl-only.net> To: Matthias Apitz <guru@unixarea.de> Cc: FreeBSD Current <freebsd-current@freebsd.org> Subject: Re: seldom crashes on Dell E6330 with 12-CURRENT Message-ID: <32C7E9E5-A51C-4836-9939-0D000016808C@dsl-only.net> In-Reply-To: <20160726055015.GB2981@c720-r292778-amd64> References: <AA0CB035-FE90-4E7B-8EC6-77F3D83D5451@dsl-only.net> <20160726055015.GB2981@c720-r292778-amd64>
next in thread | previous in thread | raw e-mail | index | archive | help
On 2016-Jul-25, at 10:50 PM, Matthias Apitz <guru@unixarea.de> wrote: >=20 > El d=C3=ADa Monday, July 25, 2016 a las 05:00:59PM -0700, Mark Millard = escribi=C3=B3: >=20 >> Matthias Apitz guru at unixarea.de wrote on Mon Jul 25 16:10:52 UTC = 2016 : >>=20 >>> On Monday, 25 July 2016 17:11:23 CEST, Eric van Gyzen <vangyzen at = FreeBSD.org> wrote: >=20 >>>> What file system are you using?=20 >>> UFS; I followed the good instructions about new SSD disk = configuration; that's why I now have swap as plain file :-(=20 >>=20 >> Unfortunately see = https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=3D206048 : >>=20 >> 11.0-CURRENT -r293227 (and others) arm (rpi2/BeagleBone Black) amd64 = etc: swapfile usage hangs; swap partition works . >>=20 >> As far as I know it still applies for the problems that can occur for = plain-file based swap files. The list of comments covers more than just = armv6 as having example failures. >>=20 >=20 > Thanks for the pointer to the bug issue. I remembered, that I created > the swap file as a so called sparse file (dd ... bs=3D1m seek=3D8192 = count=3D0) and > this is still visible with du(1): >=20 > # du -sh /usr/swap01 ; ls -lh /usr/swap01 > 95M /usr/swap01 > -rw------- 1 root wheel 8,0G 25 jul. 08:19 /usr/swap01 >=20 > I have now unmounted the swap and re-created it with real blocks: >=20 > # swapoff -a > swapoff: removing /dev/md99 as swap device >=20 > # dd if=3D/dev/zero of=3D/usr/swap01 bs=3D1m count=3D8192 > 8192+0 records in > 8192+0 records out > 8589934592 bytes transferred in 43.594277 secs (197042712 bytes/sec) > # du -sh /usr/swap01 ; ls -lh /usr/swap01 > 8,0G /usr/swap01 > -rw------- 1 root wheel 8,0G 26 jul. 07:24 /usr/swap01 >=20 > I will first give this a try. If the crash rehappens, I will move it = to > a real freebsd-swap partition. FYI: All my uses and testing of swap files used such a dd command to = populate the file with blocks. I've never even tried a sparse file for = such a thing. My experience indicates that this will not remove the problem if the = swap file is in a file system on a partition with other file system = activity (at least in the same file system?). The only type of context that I've had a swap file work over lots of use = is when I used a whole partition containing just one UFS file system = that only had the swap file added after the UFS file system was created. = In other words: About the closest thing to being a swap partition that = is still file based. I've only done this on TARGET_ARCH=3Dpowerpc and = TARGET_ARCH=3Dpowerpc64. I tried it for them because TRIM was possible = in the context: it was a SATA context with SSDs, not a USB context. (I = did this during my very first FreeBSD experiments. I only learned later = of problems with other variations.) My other, later contexts do not have TRIM as possible (for example, USB) = and so I did not do that. It is these that I had troubles with and later = switched to using a swap partition instead. [I will not have access to the powerpc's for weeks.] >=20 > While saying 'crash', I now remember that in the two cases which I = named > 'hard locked', the system was still alive in the sense of echoing = typed > chars, it was only impossible to start new commands or login on = another > console. This points too in the direction of a disk access or swap = problem. >=20 > Thanks >=20 > matthias =3D=3D=3D Mark Millard markmi at dsl-only.net
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?32C7E9E5-A51C-4836-9939-0D000016808C>