Re: devel/llvm13 failed to reclaim memory on 8 GB Pi4 running -current [UFS context: used the whole swap space too]

On 2022-Jan-28, at 00:31, Mark Millard <marklmi@yahoo.com> wrote:

>> . . .
> 
> UFS context:
> 
> . . .;  load averages:   . . . MaxObs:   5.47,   4.99,   4.82
> . . . threads:    . . ., 14 MaxObsRunning
> . . .
> Mem: . . ., 6457Mi MaxObsActive, 1263Mi MaxObsWired, 7830Mi MaxObs(Act+Wir+Lndry)
> Swap: 8192Mi Total, 8192Mi Used, K Free, 100% Inuse, 8192Mi MaxObsUsed, 14758Mi MaxObs(Act+Lndry+SwapUsed), 16017Mi MaxObs(Act+Wir+Lndry+SwapUsed)
> 
> 
> Console:
> 
> swap_pager: out of swap space
> swp_pager_getswapspace(4): failed
> swp_pager_getswapspace(1): failed
> swp_pager_getswapspace(1): failed
> swp_pager_getswapspace(2): failed
> swp_pager_getswapspace(2): failed
> swp_pager_getswapspace(4): failed
> swp_pager_getswapspace(1): failed
> swp_pager_getswapspace(9): failed
> swp_pager_getswapspace(4): failed
> swp_pager_getswapspace(7): failed
> swp_pager_getswapspace(29): failed
> swp_pager_getswapspace(9): failed
> swp_pager_getswapspace(1): failed
> swp_pager_getswapspace(2): failed
> swp_pager_getswapspace(1): failed
> swp_pager_getswapspace(4): failed
> swp_pager_getswapspace(1): failed
> swp_pager_getswapspace(10): failed
> 
> . . . Then some time with no messages . . .
> 
> vm_pageout_mightbe_oom: kill context: v_free_count: 7740, v_inactive_count: 1
> Jan 27 23:01:07 CA72_UFS kernel: pid 57238 (c++), jid 3, uid 0, was killed: failed to reclaim memory
> swp_pager_getswapspace(2): failed
> 
> 
> Note: The "vm_pageout_mightbe_oom: kill context:"
> notice is one of the few parts of an old reporting
> patch Mark J. had supplied (long ago) that still
> fits in the modern code (or that I was able to keep
> updated enough to fit, anyway). It is another of the
> personal updates that I keep in my source trees,
> such as in /usr/main-src/ .
> 
> diff --git a/sys/vm/vm_pageout.c b/sys/vm/vm_pageout.c
> index 36d5f3275800..f345e2d4a2d4 100644
> --- a/sys/vm/vm_pageout.c
> +++ b/sys/vm/vm_pageout.c
> @@ -1828,6 +1828,8 @@ vm_pageout_mightbe_oom(struct vm_domain *vmd, int page_shortage,
>         * start OOM.  Initiate the selection and signaling of the
>         * victim.
>         */
> +       printf("vm_pageout_mightbe_oom: kill context: v_free_count: %u, v_inactive_count: %u\n",
> +          vmd->vmd_free_count, vmd->vmd_pagequeues[PQ_INACTIVE].pq_cnt);
>        vm_pageout_oom(VM_OOM_MEM);
> 
>        /*
> 
> 
> Again, I'd used vm.pfault_oom_attempts inappropriately
> for running out of swap (although with UFS it did do
> a kill fairly soon):
> 
> # Delay when persistent low free RAM leads to
> # Out Of Memory killing of processes:
> vm.pageout_oom_seq=120
> #
> # For plunty of swap/paging space (will not
> # run out), avoid pageout delays leading to
> # Out Of Memory killing of processes:
> vm.pfault_oom_attempts=-1
> #
> # For possibly insufficient swap/paging space
> # (might run out), increase the pageout delay
> # that leads to Out Of Memory killing of
> # processes (showing defaults at the time):
> #vm.pfault_oom_attempts= 3
> #vm.pfault_oom_wait= 10
> # (The multiplication is the total but there
> # are other potential tradoffs in the factors
> # multiplied, even for nearly the same total.)
> 
> I'll change:
> 
> vm.pfault_oom_attempts
> vm.pfault_oom_wait
> 
> and reboot --and start the bulk somewhat before
> going to bed.
> 
> 
> For reference:
> 
> [00:02:13] [01] [00:00:00] Building devel/llvm13 | llvm13-13.0.0_3
> [07:37:05] [01] [07:34:52] Finished devel/llvm13 | llvm13-13.0.0_3: Failed: build
> 
> 
> [ 65% 4728/7265] . . . flang/lib/Evaluate/fold-designator.cpp
> [ 65% 4729/7265] . . . flang/lib/Evaluate/fold-integer.cpp
> FAILED: tools/flang/lib/Evaluate/CMakeFiles/obj.FortranEvaluate.dir/fold-integer.cpp.o 
> [ 65% 4729/7265] . . . flang/lib/Evaluate/fold-logical.cpp
> [ 65% 4729/7265] . . . flang/lib/Evaluate/fold-complex.cpp
> [ 65% 4729/7265] . . . flang/lib/Evaluate/fold-real.cpp
> 
> So the flang/lib/Evaluate/fold-integer.cpp one was the one killed.
> 
> Notably, the specific sources being compiled are different
> than in the ZFS context report. But this might be because
> of my killing ninja explicitly in the ZFS context, before
> killing the running compilers.
> 
> Again, using the options to avoid building the Fortran
> compiler probably avoids such memory use --if you do not
> need the Fortran compiler.


UFS based on instead using (not vm.pfault_oom_attempts=-1):

vm.pfault_oom_attempts= 3
vm.pfault_oom_wait= 10

It reached swap-space-full:

. . .;  load averages:   . . . MaxObs:   5.42,   4.98,   4.80
. . . threads:    . . ., 11 MaxObsRunning
. . .
Mem: . . ., 6482Mi MaxObsActive, 1275Mi MaxObsWired, 7832Mi MaxObs(Act+Wir+Lndry)
Swap: 8192Mi Total, 8192Mi Used, K Free, 100% Inuse, 4096B In, 81920B Out, 8192Mi MaxObsUsed, 14733Mi MaxObs(Act+Lndry+SwapUsed), 16007Mi MaxObs(Act+Wir+Lndry+SwapUsed)


swap_pager: out of swap space
swp_pager_getswapspace(5): failed
swp_pager_getswapspace(25): failed
swp_pager_getswapspace(1): failed
swp_pager_getswapspace(31): failed
swp_pager_getswapspace(6): failed
swp_pager_getswapspace(1): failed
swp_pager_getswapspace(25): failed
swp_pager_getswapspace(10): failed
swp_pager_getswapspace(17): failed
swp_pager_getswapspace(27): failed
swp_pager_getswapspace(5): failed
swp_pager_getswapspace(11): failed
swp_pager_getswapspace(9): failed
swp_pager_getswapspace(29): failed
swp_pager_getswapspace(2): failed
swp_pager_getswapspace(1): failed
swp_pager_getswapspace(9): failed
swp_pager_getswapspace(20): failed
swp_pager_getswapspace(4): failed
swp_pager_getswapspace(21): failed
swp_pager_getswapspace(11): failed
swp_pager_getswapspace(2): failed
swp_pager_getswapspace(21): failed
swp_pager_getswapspace(2): failed
swp_pager_getswapspace(1): failed
swp_pager_getswapspace(2): failed
swp_pager_getswapspace(3): failed
swp_pager_getswapspace(3): failed
swp_pager_getswapspace(2): failed
swp_pager_getswapspace(1): failed
swp_pager_getswapspace(20): failed
swp_pager_getswapspace(2): failed
swp_pager_getswapspace(1): failed
swp_pager_getswapspace(16): failed
swp_pager_getswapspace(6): failed
swap_pager: out of swap space
swp_pager_getswapspace(4): failed
swp_pager_getswapspace(9): failed
swp_pager_getswapspace(17): failed
swp_pager_getswapspace(30): failed
swp_pager_getswapspace(1): failed

. . . Then some time with no messages . . .

vm_pageout_mightbe_oom: kill context: v_free_count: 7875, v_inactive_count: 1
Jan 28 14:36:44 CA72_UFS kernel: pid 55178 (c++), jid 3, uid 0, was killed: failed to reclaim memory
swp_pager_getswapspace(11): failed


So, not all that much different from how the
vm.pfault_oom_attempts=-1 example looked.


[00:01:00] [01] [00:00:00] Building devel/llvm13 | llvm13-13.0.0_3
[07:41:39] [01] [07:40:39] Finished devel/llvm13 | llvm13-13.0.0_3: Failed: build

Again it killed:

FAILED: tools/flang/lib/Evaluate/CMakeFiles/obj.FortranEvaluate.dir/fold-integer.cpp.o

So, basically the same stopping area as for the
vm.pfault_oom_attempts=-1 example.


I'll set things up for swap totaling to 30 GiBytes, reboot,
and start it again. This will hopefully let me see and
report MaxObs??? figures for a successful build when there
is RAM+SWAP: 38 GiBytes. So: more than 9 GiBytes per compiler
instance (mean).

===
Mark Millard
marklmi at yahoo.com