FreeBSD on 64MB memory

[Ask Bjørn Hansen]

Hi,

I have an old Soekris system with 64MB memory that I upgraded from 10.3 to 11.1 recently. Since then it’s started hanging every few days.

Today I happened to have a “top” instance running on the serial console. The system is minimally responsive to the network (ICMP and CARP are working, but no services).

From the top output it’s not clear what resource it’s out of.  There’s no swap configured, but that what it looks like it’s trying to do? 

The ‘pf purge’ process is suspicious. There are no pf rules configured on the system (it should be all disabled).

Any suggestions?  (Other than “seriously … 64MB memory?!”).


Ask


last pid:  2228;  load averages:  0.63,  0.65,  0.70  up 0+21:13:56    04:50:47
36 processes:  2 running, 33 sleeping, 1 waiting
CPU:  0.1% user,  0.0% nice, 11.3% system,  2.4% interrupt, 86.2% idle
Mem: 1616K Active, 10M Inact, 28M Wired, 3099K Buf, 1768K Free
Swap:

  PID    UID    THR PRI NICE   SIZE    RES STATE    TIME    WCPU COMMAND
   11      0      1 155 ki31     0K     8K RUN     16.8H  75.53% idle
    0      0      7 -16    -     0K    64K swapin 155:10  12.00% kernel
   16      0      3 -16    -     0K    24K psleep  10:04   8.15% pagedaemon
   12      0     14 -64    -     0K   112K WAIT    27:21   2.80% intr
    6      0      1 -16    -     0K     8K pftm     8:56   0.73% pf purge
 1027      0      1  20    0  7272K  1140K RUN      6:04   0.52% top
    7      0      1 -16    -     0K     8K -        2:57   0.18% rand_harvestq
   21      0      1  16    -     0K     8K syncer   0:22   0.05% syncer
   22      0      1  21    -     0K     8K vlruwt   0:07   0.01% vnlru
   19      0      1  20    -     0K     8K psleep   0:08   0.01% bufdaemon
  788      0      1  20    0  5920K  1752K select   0:04   0.01% syslogd
   20      0      1  20    -     0K     8K -        0:07   0.01% bufspacedaemon
  911      0      1  20    0  8816K  8844K kmem a  43:41   0.00% ntpd
  996      0      1  20    0 13628K  4620K kmem a   0:06   0.00% sshd
  985      0      1  20    0  5952K   584K kmem a   0:07   0.00% cron
  709      0      1  20    0  7300K  3364K kmem a   0:01   0.00% devd
 2227      0      1  24    0  5952K  1232K kmem a   0:00   0.00% cron