Date: Tue, 15 Mar 2016 07:20:51 -0700 (PDT) From: "Jeffrey Bouquet" <jbtakk@iherebuywisely.com> To: "FreeBSD Current" <freebsd-current@freebsd.org> Cc: "current@freebsd.org" <current@freebsd.org>, "Ian Lepore" <ian@freebsd.org>, "Adrian Chadd" <adrian.chadd@gmail.com>, "Mark Johnston" <markj@freebsd.org>, "Gary Jennejohn" <gljennjohn@gmail.com> Subject: Re: how to recycle Inact memory more aggressively? Message-ID: <E1afpq7-0005Cs-NX@rmm6prod02.runbox.com> In-Reply-To: <56E7AF22.1020405@gmx.de>
next in thread | previous in thread | raw e-mail | index | archive | help
rsync... see bottom posting On Tue, 15 Mar 2016 07:43:46 +0100, olli hauer <ohauer@gmx.de> wrote: > On 2016-03-14 15:19, Ian Lepore wrote: > > On Sun, 2016-03-13 at 19:08 -0700, Adrian Chadd wrote: > >> On 13 March 2016 at 18:51, Mark Johnston <markj@freebsd.org> wrote: > >>> On Sun, Mar 13, 2016 at 06:33:46PM -0700, Adrian Chadd wrote: > >>>> Hi, > >>>> > >>>> I can reproduce this by doing a mkimage on a large destination > >>>> file > >>>> image. it looks like it causes all the desktop processes to get > >>>> paged > >>>> out whilst it's doing so, and then the whole UI freezes until it > >>>> catches up. > >>> > >>> mkimg(1) maps the destination file with MAP_NOSYNC, so if it's > >>> larger > >>> than RAM, I think it'll basically force the pagedaemon to write out > >>> the > >>> image as it tries to reclaim pages from the inactive queue. This > >>> can > >>> cause stalls if the pagedaemon blocks waiting for some I/O to > >>> complete. > >>> The user/alc/PQ_LAUNDRY branch helps alleviate this problem by > >>> using a > >>> different thread to launder dirty pages. I use mkimg on various > >>> desktop > >>> machines to build bhyve images and have noticed the problem you're > >>> describing; PQ_LAUNDRY helps quite a bit in that case. But I don't > >>> know > >>> why this would be a new problem. > >>> > >> > >> That's why I'm confused. I just know that it didn't used to cause the > >> whole UI to hang due to paging. > >> > >=20 > > I've been noticing this too. This machine runs 10-stable and this use > > of the swap began happening recently when I updated from 10-stable > > around the 10.2 release time to 10-stable right about when the 10.3 > > code freeze began. > >=20 > > In my case I have no zfs anything here. I noticed the problem bigtime > > yesterday when rsync was syncing a ufs filesystem of about 500GB from > > one disk to another (probably 70-80 GB actually needed copying). My > > desktop apps were noticibly unresponsive when I activated a window that > > had been idle for a while (like it would take a couple seconds for the > > app to begin responding). I could see lots of swap In happening in top > > during this unresponsiveness, and noticible amounts of Out activity > > when nothing was happening except the rsync. > >=20 > > This is amd64, 12GB ram, 16GB swap, a tmpfs had about 400MB in it at > > the time. Prior to the update around the 10.3 freeze, this machine > > would never touch the swap no matter what workload I threw at it (this > > rsync stuff happens every day, it's the usual workload). > >=20 >=20 > I'm not sure if it is the same problem, or port related. >=20 > On two systems without zfs but with many files e.g. svn servers I see now > from time to time they are running out of swap. >=20 > kernel: swap_pager_getswapspace(9): failed > kernel: swap_pager_getswapspace(16): failed > ... >=20 > It also happened on one system during the nightly periodic tasks holding > only millions of backup files. >=20 > $ freebsd-version -ku > 10.2-RELEASE-p9 > 10.2-RELEASE-p13 >=20 >=20 > _______________________________________________ > freebsd-current@freebsd.org mailing list > https://lists.freebsd.org/mailman/listinfo/freebsd-current > To unsubscribe, send any mail to "freebsd-current-unsubscribe@freebsd.org" Just a point I've bought up elsewhere... I've, if I recall, wrecked several filesystems (although EIDE) using rsync = at the normal bus rate, and sometimes thumbdrives with whatever filesystem type on them. I settled on --bwlimit=3D1500, max for unattended rsync usage and almost = every day use --bwlimit=3D700. The latter enables several resource-intensive processes ( music, classical = music videos, svn, pkg, browsing, etc) to proceed apace concurrently on the desktop (SATA not EIDE) with nary a hang = nor slowdown. If I recall, the usual speed is 10000 so that is less than ten percent, if = I recall, of the usual speed. YMMV. J. PS as an afterthough, it would be useful if that were more prominent on the= man page somewhere or even in the port's pkg-message or pkg-description.=20=20 The SATA more robust than EIDE on FreeBSD that I've come across, though I p= refer not to hint at because I believe it to be the fault of EIDE firmware rather than FreeBSD code. FWIW.=
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?E1afpq7-0005Cs-NX>