Re: Can not build kernel on 1GB VM

On Tue, Apr 19, 2022 at 08:52:00AM +0200, Wojciech Puchar wrote:
> try
> 
> sysctl -w vm.overcommit=1

No improvement.


> On Fri, 15 Apr 2022, Michael Wayne wrote:
> 
> > I have a VM with 1GB RAM running FreeBSD 12.1-RELEASE-p3
> >
> > I'm trying to upgrade the machine to 12.3 and having swap failures.
> >
> > This machine runs bird to advertise BGP, ssh and not much else so
> > the small amount of RAM is (usually) fine.
> >
> > For a long time, there was a 1 GB swap file which handled the
> > occasional time when excess memory got used.
> >
> > Machine needs a custom kernel for BGP, the conf file consists of:
> >   include GENERIC
> >   ident ROUTING
> >   options TCP_SIGNATURE
> >
> >
> > Today, while building the 12.3 kernel with:
> >   cd /usr/src
> >   sudo make toolchain
> >   sudo make buildkernel KERNCONF=ROUTING
> > the machine ran out of swap. with a bunch of messages like:
> >   Apr 15 12:11:26 g1 kernel: swap_pager: indefinite wait buffer: bufobj: 0, blkno: 240593, size: 4096
> >   Apr 15 12:11:35 g1 kernel: swap_pager: indefinite wait buffer: bufobj: 0, blkno: 236224, size: 16384
> >   Apr 15 12:11:37 g1 kernel: swap_pager: indefinite wait buffer: bufobj: 0, blkno: 245, size: 12288
> >   Apr 15 12:11:46 g1 kernel: swap_pager: indefinite wait buffer: bufobj: 0, blkno: 240593, size: 4096
> >   Apr 15 12:11:55 g1 kernel: swap_pager: indefinite wait buffer: bufobj: 0, blkno: 236224, size: 16384
> >   Apr 15 12:11:57 g1 kernel: swap_pager: indefinite wait buffer: bufobj: 0, blkno: 245, size: 12288
> >
> > Thinking it was a sawp space issue, I increased the swap to 4 GB and
> > tried again with the same results. Boot gave the kern.maxswzone message,
> > I ignored it as I had planned to change as soon as I completed the build.
> >
> > So I pulled up top in a console window and watched swap during the
> > build.  About 400 MB of RAM was free and about 3 MB of swap was
> > used when the machine started linking the kernel:
> >   ctfmerge -L VERSION -g -o kernel.full ...
> > While this command was running, I saw swap usage go to ~5MB (so
> > just over 1%), then started seeing processes being killed due to
> > out of swap space.
> >
> > So, how to proceed?