Re: Server became inaccessible because it ran out of swap space

Hi,

On 05/07/2024 07:56, Odhiambo Washington wrote:
> I have a server with 64GB RAM, 2CPUs each with 16 cores. I have also
> configured 13GB or swap space.
> 
> ```
> root@gw:/usr/local/bhyve-vms/scripts # swapinfo
> Device          1K-blocks     Used    Avail Capacity
> /dev/ada0p3       3163136   703316  2459820    22%
> /dev/md0.eli     10485760   709352  9776408     7%
> Total            13648896  1412668 12236228    10%
> root@gw:/usr/local/bhyve-vms/scripts #
> ```
> 
> A number of times it has become inaccessible until I do a hard reboot and
> this has been caused by what I believe is running out of swap.
> 
> Below is what I have obtained from /var/log/messages after I rebooted.
> 
> How do I identify the culprit? Arrest the situation?
> 
> 
> ```
> Jul  5 06:50:56 gw kernel: failed
> Jul  5 06:52:11 gw kernel: failed
> Jul  5 06:52:11 gw kernel: out of swap space
> Jul  5 06:52:11 gw kernel: failed
> Jul  5 06:52:11 gw kernel: failed
> Jul  5 06:52:12 gw kernel: failed
> Jul  5 06:52:12 gw kernel: failed
> Jul  5 06:54:06 gw kernel: out of swap space
> Jul  5 06:54:06 gw kernel: failed
> Jul  5 07:16:30 gw kernel: pid 4076 (bhyve), jid 0, uid 0, was killed:
> failed to reclaim memory
> Jul  5 07:16:30 gw kernel: pid 4076 (bhyve), jid 0, uid 0, was killed:
> failed to reclaim memory
> Jul  5 07:16:30 gw kernel: tap4: link state changed to DOWN
> Jul  5 07:16:30 gw kernel: out of swap space
> Jul  5 07:16:30 gw kernel: failed
> Jul  5 07:16:30 gw kernel: failed
> Jul  5 07:16:30 gw kernel: failed
> Jul  5 07:16:30 gw kernel: pid 20849 (bhyve), jid 0, uid 0, was killed:
> failed to reclaim memory
> Jul  5 07:16:30 gw kernel: pid 20849 (bhyve), jid 0, uid 0, was killed:
> failed to reclaim memory
> Jul  5 07:16:30 gw kernel: tap5: link state changed to DOWN
> Jul  5 07:16:30 gw kernel: failed
> Jul  5 07:16:30 gw kernel: failed
> Jul  5 07:16:30 gw kernel: sonewconn: pcb 0xfffff8002866d100
> (local:/var/run/wsgi.38620.0.1.sock): Listen queue overflow: 151 already in
> queue awaiting acceptance (1 occurrences), euid 0, rgid 0, jail 0
> Jul  5 07:16:30 gw kernel: pid 3591 (bhyve), jid 0, uid 0, was killed:
> failed to reclaim memory
> Jul  5 07:16:30 gw kernel: pid 3591 (bhyve), jid 0, uid 0, was killed:
> failed to reclaim memory
> Jul  5 07:16:30 gw kernel: tap3: link state changed to DOWN
> Jul  5 07:16:30 gw kernel: failed
> Jul  5 07:16:30 gw kernel: out of swap space
> Jul  5 07:16:30 gw kernel: failed
> Jul  5 07:16:31 gw kernel: failed
> Jul  5 07:16:31 gw kernel: failed
> Jul  5 07:16:32 gw kernel: out of swap space
> Jul  5 07:16:33 gw kernel: out of swap space
> Jul  5 07:16:33 gw kernel: failed
> Jul  5 07:16:33 gw kernel: failed
> Jul  5 07:16:34 gw kernel: out of swap space
> Jul  5 07:16:34 gw kernel: failed
> Jul  5 07:16:36 gw kernel: failed
> Jul  5 07:16:36 gw kernel: failed
> Jul  5 07:16:36 gw kernel: failed
> Jul  5 07:16:36 gw kernel: failed
> Jul  5 07:16:36 gw kernel: failed
> Jul  5 07:16:37 gw kernel: failed
> Jul  5 07:16:37 gw kernel: failed
> Jul  5 07:16:37 gw kernel: failed
> Jul  5 07:16:37 gw kernel: failed
> Jul  5 07:16:37 gw kernel: failed
> Jul  5 07:16:37 gw kernel: failed
> Jul  5 07:16:37 gw kernel: failed
> Jul  5 07:16:38 gw kernel: failed
> ```
> 
> 

I'm not sure but looking at the bhyve processes being killed, it reminds 
of an earlier issue that was solved with:

`vm.disable_swapspace_pageouts=1`

Cheers,
David