On Tue, Nov 28, 2023 at 04:50:05PM +0100, Laurent CARON wrote: > Le 28/11/2023 à 12:12, Claudio Jeker a écrit : > > So the problem is that the malloc space is filled by > > a) 26540K of devbuf -- because of the multiqueue support in ixl > > b) 63493K of ACPI -- what the heck ACPI?!? > > and then there is not enough space for rtable. A full table requires > > in your example 50816K of rtable malloc space. > > > > Now on amd64 all of this needs to fit into 128MB which is impossible. > > > > You can use config(8) and bsd.re-config(5) to adjust the nkmempg variable > > to something like 131072 (which is 4 times the default size). > > This can be verified with `sysctl vm.nkmempages` > > > > Now ixl(4) and ACPI should not be such pigs but in the end 128MB of kernel > > malloc space is just stupidly small on a system with 128GB of memory. > > > Hi Claudio, > > Thanks. > > I bumped nkmempg to 131072 > > ==== > > # config -e -o bsd.new /bsd > > ukc> nkmempg 131072 > > quit > > ==== > > Then rebooted with the very same issue. > > It seems the nkmempg variable is not properly takes into account since > 'sysctl vm.nkmempages' still shows 32768 after reboot > > ==== > > # sysctl vm.nkmempages vm.nkmempages=32768 > > ==== > > # config -e -o bsd.new /bsd OpenBSD 7.4 (GENERIC.MP) #0: Sun Oct 22 12:13:42 > MDT 2023 > [email protected]:/usr/src/sys/arch/amd64/compile/GENERIC.MP > Enter 'help' for information ukc> nkmempg nkmempages = 262144 ==== > > Modifying /etc/bsd.re-config and rebooting (twice) didn't help either. > > I 'had'to recompile kernel (after modifying: /usr/src/sys/kern/kern_malloc.c > with '#define NKMEMPAGES 262144 '), the issue is not occuring again. > > Do you recomend using this approach to mitigate the issue, or is there a > more 'long term' fix ?
The problem is that the symbol nkmempages moved into .bss and is therefor no longer modifiable by config(8). I think you can still use ukc via boot -c to alter it (but that is not sticky). The alternative is to set "option NKMEMPAGES=131072" in your GENERIC config file (or option NKMEMPAGES_MAX=131072). See also options(4). Long term is the fix this proper. All of this was built when computers had 100MB of memory not 100GB. -- :wq Claudio
