Date: Thu, 20 May 2021 09:44:20 +0300 From: Andriy Gapon <avg@FreeBSD.org> To: Alan Somers <asomers@freebsd.org>, Konstantin Belousov <kostikbel@gmail.com> Cc: Mark Johnston <markj@freebsd.org>, FreeBSD Hackers <freebsd-hackers@freebsd.org> Subject: Re: The pagedaemon evicts ARC before scanning the inactive page list Message-ID: <4122a6cf-2da0-0816-96af-f2058d48435e@FreeBSD.org> In-Reply-To: <CAOtMX2gaehOBikJfbtt0ABQu1fimC_Ai7ac12DtdF1qNpk_MLQ@mail.gmail.com> References: <CAOtMX2gvkrYS0zYYYtjD%2BAaqv62MzFYFhWPHjLDGXA1=H7LfCg@mail.gmail.com> <YKQ1biSSGbluuy5f@nuc> <CAOtMX2he1YBidG=zF=iUQw%2BOs7p=gWMk-sab00NVr0nNs=Cwog@mail.gmail.com> <YKQ7YhMke7ibse6F@nuc> <CAOtMX2hT2XR=fyU6HB11WHbRx4qtNoyPHkX60g3JXXH9JWrObQ@mail.gmail.com> <YKSFCuNAkPH9Du5E@kib.kiev.ua> <CAOtMX2jAE58CtSHk4vJXXz0_0YC5ejmRx4DnArKGzksNFg51hQ@mail.gmail.com> <YKSRPjOGjHVe0aOa@kib.kiev.ua> <CAOtMX2gaehOBikJfbtt0ABQu1fimC_Ai7ac12DtdF1qNpk_MLQ@mail.gmail.com>
next in thread | previous in thread | raw e-mail | index | archive | help
On 19/05/2021 23:28, Alan Somers wrote: > Follow-up: > All of the big inactive-memory consumers were files on FUSE file systems that > were being exported as CTL LUNs. ZFS files exported by CTL do not use any res > or inactive memory. I didn't test UFS. Curiously, removing the LUN does not > free the memory, but shutting down the FUSE daemon does. A valid workaround is > to set the vfs.fusefs.data_cache_mode sysctl to 0. That prevents the kernel > from caching any data from the FUSE file system. I've tested this on both > FreeBSD 12.2 and 13.0 . Should the kernel do a better job of reclaiming > inactive memory before ARC? Yes, but in my case it's better not to create so > much inactive memory in the first place. Thanks for everybody's help, > especially kib's tip about "vmstat -o". Nevertheless, the larger problem still exists. I can confirm it on my system and right now I am not using fusefs at all. I do, however, use some programs that like to mmap some big data a lot. The current pageout + ARC reclaim code really oppresses the ARC. I think that Kostik and Mark made some good suggestion on how that can be fixed. -- Andriy Gapon
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?4122a6cf-2da0-0816-96af-f2058d48435e>