If a process is consuming too much memory then the kernel "Out of Memory" (OOM) killer will automatically kill the offending process. It sounds like this may have happened to your job. The kernel log should show OOM killer actions, so use the "dmesg" command to see what happened, e.g.

dmesg | less

You will see a OOM killer messages, something like the following:

[   54.125380] Out of memory: Kill process 8320 (stress-ng-brk) score 324 or sacrifice child
[   54.125382] Killed process 8320 (stress-ng-brk) total-vm:1309660kB, anon-rss:1287796kB, file-rss:76kB
[   54.522906] gmain invoked oom-killer: gfp_mask=0x24201ca, order=0, oom_score_adj=0
[   54.522908] gmain cpuset=accounts-daemon.service mems_allowed=0
[   54.522912] CPU: 6 PID: 1032 Comm: gmain Not tainted 4.4.0-0-generic #3-Ubuntu
[   54.522913] Hardware name: Intel Corporation Skylake Client platform/Skylake DT DDR4 RVP8, BIOS SKLSE2R1.R00.B089.B00.1506160228 06/16/2015
[   54.522914]  0000000000000000 000000002d879fe9 ffff88016d727a58 ffffffff813d8604
[   54.522915]  ffff88016d727c50 ffff88016d727ac8 ffffffff8120272e 0000000000000015
[   54.522916]  0000000000000000 ffff880080ab3600 ffff880086725880 ffff88016d727ab8
[   54.522917] Call Trace:
[   54.522921]  [<ffffffff813d8604>] dump_stack+0x44/0x60
[   54.522924]  [<ffffffff8120272e>] dump_header+0x5a/0x1c5
[   54.522926]  [<ffffffff81376bd8>] ? apparmor_capable+0xb8/0x120
[   54.522928]  [<ffffffff8118b472>] oom_kill_process+0x202/0x3b0
[   54.522929]  [<ffffffff8118b885>] out_of_memory+0x215/0x460
[   54.522931]  [<ffffffff81191740>] __alloc_pages_nodemask+0x9b0/0xb40
[   54.522933]  [<ffffffff811da7cc>] alloc_pages_current+0x8c/0x110
[   54.522934]  [<ffffffff81187d75>] __page_cache_alloc+0xb5/0xc0
[   54.522935]  [<ffffffff81189f4a>] filemap_fault+0x14a/0x3f0
[   54.522937]  [<ffffffff811b6140>] __do_fault+0x50/0xe0
[   54.522938]  [<ffffffff811b9b82>] handle_mm_fault+0xf92/0x1840
[   54.522939]  [<ffffffff812526a7>] ? eventfd_ctx_read+0x67/0x210
[   54.522941]  [<ffffffff81068517>] __do_page_fault+0x197/0x400
[   54.522942]  [<ffffffff810687a2>] do_page_fault+0x22/0x30
[   54.522944]  [<ffffffff8180e2f8>] page_fault+0x28/0x30
[   54.522945] Mem-Info:
[   54.522947] active_anon:788399 inactive_anon:33532 isolated_anon:0
                active_file:83 inactive_file:37 isolated_file:0
                unevictable:1 dirty:10 writeback:0 unstable:0
                slab_reclaimable:5166 slab_unreclaimable:13868
                mapped:5646 shmem:9752 pagetables:4476 bounce:0
                free:7576 free_pcp:0 free_cma:0
[   54.522948] Node 0 DMA free:15476kB min:28kB low:32kB high:40kB active_anon:144kB inactive_anon:216kB active_file:0kB inactive_file:0kB unevictable:0kB isolated(anon):0kB isolated(file):0kB present:15984kB managed:15888kB mlocked:0kB dirty:0kB writeback:0kB mapped:80kB shmem:80kB slab_reclaimable:0kB slab_unreclaimable:48kB kernel_stack:0kB pagetables:4kB unstable:0kB bounce:0kB free_pcp:0kB local_pcp:0kB free_cma:0kB writeback_tmp:0kB pages_scanned:0 all_unreclaimable? yes
[   54.522951] lowmem_reserve[]: 0 2072 3862 3862
[   54.522952] Node 0 DMA32 free:11220kB min:4204kB low:5252kB high:6304kB active_anon:1711968kB inactive_anon:80964kB active_file:236kB inactive_file:100kB unevictable:0kB isolated(anon):0kB isolated(file):0kB present:2206296kB managed:2125964kB mlocked:0kB dirty:36kB writeback:0kB mapped:17948kB shmem:26240kB slab_reclaimable:8988kB slab_unreclaimable:26036kB kernel_stack:2656kB pagetables:9348kB unstable:0kB bounce:0kB free_pcp:0kB local_pcp:0kB free_cma:0kB writeback_tmp:0kB pages_scanned:3776 all_unreclaimable? yes
[   54.522955] lowmem_reserve[]: 0 0 1790 1790
[   54.522956] Node 0 Normal free:3608kB min:3628kB low:4532kB high:5440kB active_anon:1441484kB inactive_anon:52948kB active_file:96kB inactive_file:48kB unevictable:4kB isolated(anon):0kB isolated(file):0kB present:1900544kB managed:1833172kB mlocked:4kB dirty:4kB writeback:0kB mapped:4556kB shmem:12688kB slab_reclaimable:11676kB slab_unreclaimable:29388kB kernel_stack:2448kB pagetables:8552kB unstable:0kB bounce:0kB free_pcp:0kB local_pcp:0kB free_cma:0kB writeback_tmp:0kB pages_scanned:924 all_unreclaimable? yes
[   54.522958] lowmem_reserve[]: 0 0 0 0
[   54.522959] Node 0 DMA: 7*4kB (UME) 3*8kB (UM) 4*16kB (UME) 4*32kB (UME) 2*64kB (U) 4*128kB (UME) 1*256kB (E) 2*512kB (ME) 3*1024kB (UME) 1*2048kB (E) 2*4096kB (M) = 15476kB
[   54.522965] Node 0 DMA32: 118*4kB (UME) 36*8kB (UME) 62*16kB (UME) 94*32kB (UME) 34*64kB (UME) 24*128kB (UME) 5*256kB (UE) 1*512kB (U) 0*1024kB 0*2048kB 0*4096kB = 11800kB
[   54.522969] Node 0 Normal: 151*4kB (UME) 39*8kB (UME) 77*16kB (UME) 38*32kB (UME) 9*64kB (ME) 0*128kB 0*256kB 0*512kB 0*1024kB 0*2048kB 0*4096kB = 3940kB
[   54.522974] Node 0 hugepages_total=0 hugepages_free=0 hugepages_surp=0 hugepages_size=1048576kB
[   54.522974] Node 0 hugepages_total=256 hugepages_free=256 hugepages_surp=0 hugepages_size=2048kB
[   54.522975] 9932 total pagecache pages
[   54.522976] 0 pages in swap cache
[   54.522976] Swap cache stats: add 1831590, delete 1831590, find 5929/10969
[   54.522977] Free swap  = 0kB
[   54.522977] Total swap = 0kB
[   54.522978] 1030706 pages RAM
[   54.522978] 0 pages HighMem/MovableOnly
[   54.522979] 36950 pages reserved
[   54.522979] 0 pages cma reserved
[   54.522979] 0 pages hwpoisoned
[   54.522980] [ pid ]   uid  tgid total_vm      rss nr_ptes nr_pmds swapents oom_score_adj name
[   54.522986] [  285]     0   285    10173     1022      23       3        0             0 systemd-journal
[   54.522988] [  312]     0   312    11192      266      22       3        0         -1000 systemd-udevd
[   54.522989] [  623]   100   623    25590      569      20       4        6             0 systemd-timesyn
[   54.522990] [  823]     0   823     5859     1723      14       3        0             0 dhclient
[   54.522991] [  917]     0   917     7152       96      18       3        2             0 systemd-logind
[   54.522992] [  936]     0   936     6310      223      16       3        0             0 smartd
[   54.522993] [  943]     0   943   112847      523      72       3        9             0 NetworkManager
[   54.522993] [  952]     0   952    84334      421      68       4        0             0 ModemManager
[   54.522994] [  957]     0   957     4797       40      15       4        0             0 atd
[   54.522995] [  961]   115   961    93456      912      80       4        0             0 whoopsie
[   54.522996] [  963]     0   963     4865       65      13       3        0             0 irqbalance
[   54.522997] [  964]   104   964    65667      224      30       4        9             0 rsyslogd
[   54.522998] [  966]     0   966    23282       34      13       3        0             0 lxcfs
[   54.522999] [  971]   105   971    10926      318      26       3        8          -900 dbus-daemon
[   54.523000] [ 1008]     0  1008     9570       82      25       3        0             0 cgmanager
[   54.523001] [ 1016]     0  1016    70808      240      41       3        0             0 accounts-daemon
[   54.523002] [ 1019]     0  1019     1119       46       8       3        0             0 ondemand
[   54.523003] [ 1022]     0  1022     7233       68      20       3        0             0 cron
[   54.523004] [ 1028]   109  1028    11218       97      26       3        3             0 avahi-daemon
[   54.523005] [ 1030]     0  1030     1807       20      10       3        0             0 sleep
[   54.523006] [ 1037]   109  1037    11185       82      25       3        0             0 avahi-daemon
[   54.523007] [ 1047]     0  1047   141966     2188     156       4        3             0 libvirtd
[   54.523008] [ 1053]     0  1053    13902      163      33       3        0         -1000 sshd
[   54.523009] [ 1057]     0  1057    69683      586      40       3       12             0 polkitd
[   54.523010] [ 1072]     0  1072    10963      134      24       3        0             0 wpa_supplicant
[   54.523011] [ 1081]     0  1081    87582      696      39       3       23             0 lightdm
[   54.523012] [ 1088]     0  1088    99946     6138      97       3       15             0 Xorg
[   54.523012] [ 1111]     0  1111     1099       45       8       3        0             0 acpid
[   54.523013] [ 1125]     0  1125    56533      191      47       4       14             0 lightdm
[   54.523014] [ 1129]   114  1129    11957      850      27       3        0             0 systemd
[   54.523015] [ 1130]   114  1130    15825      501      33       3        0             0 (sd-pam)
[   54.523029] [ 1136]   114  1136    30728      108      26       4        0             0 gnome-keyring-d
[   54.523030] [ 1138]   114  1138     1119       20       8       3        0             0 lightdm-greeter
[   54.523031] [ 1143]   114  1143    10743      145      25       3       13             0 dbus-daemon
[   54.523032] [ 1144]   114  1144   227063     2039     170       4       17             0 unity-greeter
[   54.523032] [ 1146]   114  1146    84488      626      34       3        0             0 at-spi-bus-laun
[   54.523033] [ 1151]   114  1151    10680       97      27       4        0             0 dbus-daemon
[   54.523034] [ 1153]   114  1153    51706      157      37       3        3             0 at-spi2-registr
[   54.523035] [ 1159]   114  1159    68584      154      37       3        0             0 gvfsd
[   54.523036] [ 1164]   114  1164    85325      145      32       3        0             0 gvfsd-fuse
[   54.523037] [ 1174]   114  1174    44626      121      23       3        3             0 dconf-service
[   54.523038] [ 1197]     0  1197    20665      147      44       3        0             0 lightdm
[   54.523038] [ 1201]   114  1201    11465      160      27       3        0             0 upstart
[   54.523039] [ 1204]   114  1204   144936     1323     136       4        4             0 nm-applet
[   54.523040] [ 1206]   114  1206    88647      256      41       3       26             0 indicator-messa
[   54.523041] [ 1207]   114  1207    83323      127      31       3        0             0 indicator-bluet
[   54.523042] [ 1208]   114  1208   122044       98      37       4       12             0 indicator-power
[   54.523043] [ 1209]   114  1209   132868      439      75       3        0             0 indicator-datet
[   54.523044] [ 1210]   114  1210   140272     1504     127       4        1             0 indicator-keybo
[   54.523045] [ 1211]   114  1211   134142      426      68       4        8             0 indicator-sound
[   54.523045] [ 1212]   114  1212   189042      260      47       4        0             0 indicator-sessi
[   54.523046] [ 1218]   114  1218   117391      350      89       4        0             0 indicator-appli
[   54.523047] [ 1232]     0  1232     7973       81      20       3       11             0 bluetoothd
[   54.523048] [ 1238]   114  1238   152474     1084     129       3       15             0 unity-settings-
[   54.523049] [ 1261]   114  1261   104039      719      78       4        0             0 pulseaudio
[   54.523050] [ 1272]   120  1272    45874       77      24       3        1             0 rtkit-daemon
[   54.523051] [ 1293]     0  1293    68995      324      53       3       12             0 upowerd
[   54.523052] [ 1296]   114  1296    15493      366      33       3        0             0 gconfd-2
[   54.523053] [ 1342]   110  1342    75254     1170      49       3        0             0 colord
[   54.523054] [ 1429]   113  1429    12484       98      27       3        0             0 dnsmasq
[   54.523054] [ 1430]     0  1430    12477       94      27       3        0             0 dnsmasq
[   54.523055] [ 1514]     0  1514    22408      226      49       3        0             0 sshd
[   54.523056] [ 1570]  1000  1570    11958      853      26       3        0             0 systemd
[   54.523057] [ 1571]  1000  1571    15825      501      33       3        0             0 (sd-pam)
[   54.523058] [ 1631]  1000  1631    22408      244      46       3        0             0 sshd
[   54.523058] [ 1632]  1000  1632     5779      619      16       3        0             0 bash
[   54.523059] [ 1692]   118  1692    11320       77      25       3       14             0 kerneloops
[   54.523060] [ 1745]     0  1745     3964       41      13       3        0             0 agetty
[   54.523061] [ 1768]   125  1768    13192       98      27       3        0             0 dnsmasq
[   54.523062] [ 2276]   126  2276    32160      388      58       3        0             0 exim4
[   54.523062] [ 8310]  1000  8310     5508      661      14       3        0             0 stress-ng
[   54.523063] [ 8311]  1000  8311     5508       49      13       3        0             0 stress-ng-brk
[   54.523064] [ 8312]  1000  8312     5508       46      13       3        0             0 stress-ng-brk
[   54.523065] [ 8313]  1000  8313     5508       46      13       3        0             0 stress-ng-brk
[   54.523065] [ 8314]  1000  8314     5508       46      13       3        0             0 stress-ng-brk
[   54.523066] [ 8321]  1000  8321   365871   360407     717       4        0             0 stress-ng-brk
[   54.523067] [ 8322]  1000  8322   239424   233959     470       3        0             0 stress-ng-brk
[   54.523068] [ 8323]  1000  8323   143599   138152     283       3        0             0 stress-ng-brk
[   54.523069] [ 8324]  1000  8324    54613    49145     109       3        0             0 stress-ng-brk
[   54.523070] Out of memory: Kill process 8321 (stress-ng-brk) score 363 or sacrifice child
[   54.523072] Killed process 8321 (stress-ng-brk) total-vm:1463484kB, anon-rss:1441628kB, file-rss:0kB

However, this message may have been cleared from the kernel log, so one may need to inspect the kernel logs /var/log/kern.log*

The default virtual memory setting for Linux is to over-commit memory. This means the kernel will allow one to allocate more memory than is available, allowing processes to memory map large regions because normally not all the pages in the allocation are used. However, sometimes a process will read/write to all the pages that are over committed and the kernel cannot provide enough physical memory + swap, so the OOM killer attempts to find the best candidate overcommitted process and kill it.

Answer from Colin Ian King on askubuntu.com
Top answer
1 of 2
76

If a process is consuming too much memory then the kernel "Out of Memory" (OOM) killer will automatically kill the offending process. It sounds like this may have happened to your job. The kernel log should show OOM killer actions, so use the "dmesg" command to see what happened, e.g.

dmesg | less

You will see a OOM killer messages, something like the following:

[   54.125380] Out of memory: Kill process 8320 (stress-ng-brk) score 324 or sacrifice child
[   54.125382] Killed process 8320 (stress-ng-brk) total-vm:1309660kB, anon-rss:1287796kB, file-rss:76kB
[   54.522906] gmain invoked oom-killer: gfp_mask=0x24201ca, order=0, oom_score_adj=0
[   54.522908] gmain cpuset=accounts-daemon.service mems_allowed=0
[   54.522912] CPU: 6 PID: 1032 Comm: gmain Not tainted 4.4.0-0-generic #3-Ubuntu
[   54.522913] Hardware name: Intel Corporation Skylake Client platform/Skylake DT DDR4 RVP8, BIOS SKLSE2R1.R00.B089.B00.1506160228 06/16/2015
[   54.522914]  0000000000000000 000000002d879fe9 ffff88016d727a58 ffffffff813d8604
[   54.522915]  ffff88016d727c50 ffff88016d727ac8 ffffffff8120272e 0000000000000015
[   54.522916]  0000000000000000 ffff880080ab3600 ffff880086725880 ffff88016d727ab8
[   54.522917] Call Trace:
[   54.522921]  [<ffffffff813d8604>] dump_stack+0x44/0x60
[   54.522924]  [<ffffffff8120272e>] dump_header+0x5a/0x1c5
[   54.522926]  [<ffffffff81376bd8>] ? apparmor_capable+0xb8/0x120
[   54.522928]  [<ffffffff8118b472>] oom_kill_process+0x202/0x3b0
[   54.522929]  [<ffffffff8118b885>] out_of_memory+0x215/0x460
[   54.522931]  [<ffffffff81191740>] __alloc_pages_nodemask+0x9b0/0xb40
[   54.522933]  [<ffffffff811da7cc>] alloc_pages_current+0x8c/0x110
[   54.522934]  [<ffffffff81187d75>] __page_cache_alloc+0xb5/0xc0
[   54.522935]  [<ffffffff81189f4a>] filemap_fault+0x14a/0x3f0
[   54.522937]  [<ffffffff811b6140>] __do_fault+0x50/0xe0
[   54.522938]  [<ffffffff811b9b82>] handle_mm_fault+0xf92/0x1840
[   54.522939]  [<ffffffff812526a7>] ? eventfd_ctx_read+0x67/0x210
[   54.522941]  [<ffffffff81068517>] __do_page_fault+0x197/0x400
[   54.522942]  [<ffffffff810687a2>] do_page_fault+0x22/0x30
[   54.522944]  [<ffffffff8180e2f8>] page_fault+0x28/0x30
[   54.522945] Mem-Info:
[   54.522947] active_anon:788399 inactive_anon:33532 isolated_anon:0
                active_file:83 inactive_file:37 isolated_file:0
                unevictable:1 dirty:10 writeback:0 unstable:0
                slab_reclaimable:5166 slab_unreclaimable:13868
                mapped:5646 shmem:9752 pagetables:4476 bounce:0
                free:7576 free_pcp:0 free_cma:0
[   54.522948] Node 0 DMA free:15476kB min:28kB low:32kB high:40kB active_anon:144kB inactive_anon:216kB active_file:0kB inactive_file:0kB unevictable:0kB isolated(anon):0kB isolated(file):0kB present:15984kB managed:15888kB mlocked:0kB dirty:0kB writeback:0kB mapped:80kB shmem:80kB slab_reclaimable:0kB slab_unreclaimable:48kB kernel_stack:0kB pagetables:4kB unstable:0kB bounce:0kB free_pcp:0kB local_pcp:0kB free_cma:0kB writeback_tmp:0kB pages_scanned:0 all_unreclaimable? yes
[   54.522951] lowmem_reserve[]: 0 2072 3862 3862
[   54.522952] Node 0 DMA32 free:11220kB min:4204kB low:5252kB high:6304kB active_anon:1711968kB inactive_anon:80964kB active_file:236kB inactive_file:100kB unevictable:0kB isolated(anon):0kB isolated(file):0kB present:2206296kB managed:2125964kB mlocked:0kB dirty:36kB writeback:0kB mapped:17948kB shmem:26240kB slab_reclaimable:8988kB slab_unreclaimable:26036kB kernel_stack:2656kB pagetables:9348kB unstable:0kB bounce:0kB free_pcp:0kB local_pcp:0kB free_cma:0kB writeback_tmp:0kB pages_scanned:3776 all_unreclaimable? yes
[   54.522955] lowmem_reserve[]: 0 0 1790 1790
[   54.522956] Node 0 Normal free:3608kB min:3628kB low:4532kB high:5440kB active_anon:1441484kB inactive_anon:52948kB active_file:96kB inactive_file:48kB unevictable:4kB isolated(anon):0kB isolated(file):0kB present:1900544kB managed:1833172kB mlocked:4kB dirty:4kB writeback:0kB mapped:4556kB shmem:12688kB slab_reclaimable:11676kB slab_unreclaimable:29388kB kernel_stack:2448kB pagetables:8552kB unstable:0kB bounce:0kB free_pcp:0kB local_pcp:0kB free_cma:0kB writeback_tmp:0kB pages_scanned:924 all_unreclaimable? yes
[   54.522958] lowmem_reserve[]: 0 0 0 0
[   54.522959] Node 0 DMA: 7*4kB (UME) 3*8kB (UM) 4*16kB (UME) 4*32kB (UME) 2*64kB (U) 4*128kB (UME) 1*256kB (E) 2*512kB (ME) 3*1024kB (UME) 1*2048kB (E) 2*4096kB (M) = 15476kB
[   54.522965] Node 0 DMA32: 118*4kB (UME) 36*8kB (UME) 62*16kB (UME) 94*32kB (UME) 34*64kB (UME) 24*128kB (UME) 5*256kB (UE) 1*512kB (U) 0*1024kB 0*2048kB 0*4096kB = 11800kB
[   54.522969] Node 0 Normal: 151*4kB (UME) 39*8kB (UME) 77*16kB (UME) 38*32kB (UME) 9*64kB (ME) 0*128kB 0*256kB 0*512kB 0*1024kB 0*2048kB 0*4096kB = 3940kB
[   54.522974] Node 0 hugepages_total=0 hugepages_free=0 hugepages_surp=0 hugepages_size=1048576kB
[   54.522974] Node 0 hugepages_total=256 hugepages_free=256 hugepages_surp=0 hugepages_size=2048kB
[   54.522975] 9932 total pagecache pages
[   54.522976] 0 pages in swap cache
[   54.522976] Swap cache stats: add 1831590, delete 1831590, find 5929/10969
[   54.522977] Free swap  = 0kB
[   54.522977] Total swap = 0kB
[   54.522978] 1030706 pages RAM
[   54.522978] 0 pages HighMem/MovableOnly
[   54.522979] 36950 pages reserved
[   54.522979] 0 pages cma reserved
[   54.522979] 0 pages hwpoisoned
[   54.522980] [ pid ]   uid  tgid total_vm      rss nr_ptes nr_pmds swapents oom_score_adj name
[   54.522986] [  285]     0   285    10173     1022      23       3        0             0 systemd-journal
[   54.522988] [  312]     0   312    11192      266      22       3        0         -1000 systemd-udevd
[   54.522989] [  623]   100   623    25590      569      20       4        6             0 systemd-timesyn
[   54.522990] [  823]     0   823     5859     1723      14       3        0             0 dhclient
[   54.522991] [  917]     0   917     7152       96      18       3        2             0 systemd-logind
[   54.522992] [  936]     0   936     6310      223      16       3        0             0 smartd
[   54.522993] [  943]     0   943   112847      523      72       3        9             0 NetworkManager
[   54.522993] [  952]     0   952    84334      421      68       4        0             0 ModemManager
[   54.522994] [  957]     0   957     4797       40      15       4        0             0 atd
[   54.522995] [  961]   115   961    93456      912      80       4        0             0 whoopsie
[   54.522996] [  963]     0   963     4865       65      13       3        0             0 irqbalance
[   54.522997] [  964]   104   964    65667      224      30       4        9             0 rsyslogd
[   54.522998] [  966]     0   966    23282       34      13       3        0             0 lxcfs
[   54.522999] [  971]   105   971    10926      318      26       3        8          -900 dbus-daemon
[   54.523000] [ 1008]     0  1008     9570       82      25       3        0             0 cgmanager
[   54.523001] [ 1016]     0  1016    70808      240      41       3        0             0 accounts-daemon
[   54.523002] [ 1019]     0  1019     1119       46       8       3        0             0 ondemand
[   54.523003] [ 1022]     0  1022     7233       68      20       3        0             0 cron
[   54.523004] [ 1028]   109  1028    11218       97      26       3        3             0 avahi-daemon
[   54.523005] [ 1030]     0  1030     1807       20      10       3        0             0 sleep
[   54.523006] [ 1037]   109  1037    11185       82      25       3        0             0 avahi-daemon
[   54.523007] [ 1047]     0  1047   141966     2188     156       4        3             0 libvirtd
[   54.523008] [ 1053]     0  1053    13902      163      33       3        0         -1000 sshd
[   54.523009] [ 1057]     0  1057    69683      586      40       3       12             0 polkitd
[   54.523010] [ 1072]     0  1072    10963      134      24       3        0             0 wpa_supplicant
[   54.523011] [ 1081]     0  1081    87582      696      39       3       23             0 lightdm
[   54.523012] [ 1088]     0  1088    99946     6138      97       3       15             0 Xorg
[   54.523012] [ 1111]     0  1111     1099       45       8       3        0             0 acpid
[   54.523013] [ 1125]     0  1125    56533      191      47       4       14             0 lightdm
[   54.523014] [ 1129]   114  1129    11957      850      27       3        0             0 systemd
[   54.523015] [ 1130]   114  1130    15825      501      33       3        0             0 (sd-pam)
[   54.523029] [ 1136]   114  1136    30728      108      26       4        0             0 gnome-keyring-d
[   54.523030] [ 1138]   114  1138     1119       20       8       3        0             0 lightdm-greeter
[   54.523031] [ 1143]   114  1143    10743      145      25       3       13             0 dbus-daemon
[   54.523032] [ 1144]   114  1144   227063     2039     170       4       17             0 unity-greeter
[   54.523032] [ 1146]   114  1146    84488      626      34       3        0             0 at-spi-bus-laun
[   54.523033] [ 1151]   114  1151    10680       97      27       4        0             0 dbus-daemon
[   54.523034] [ 1153]   114  1153    51706      157      37       3        3             0 at-spi2-registr
[   54.523035] [ 1159]   114  1159    68584      154      37       3        0             0 gvfsd
[   54.523036] [ 1164]   114  1164    85325      145      32       3        0             0 gvfsd-fuse
[   54.523037] [ 1174]   114  1174    44626      121      23       3        3             0 dconf-service
[   54.523038] [ 1197]     0  1197    20665      147      44       3        0             0 lightdm
[   54.523038] [ 1201]   114  1201    11465      160      27       3        0             0 upstart
[   54.523039] [ 1204]   114  1204   144936     1323     136       4        4             0 nm-applet
[   54.523040] [ 1206]   114  1206    88647      256      41       3       26             0 indicator-messa
[   54.523041] [ 1207]   114  1207    83323      127      31       3        0             0 indicator-bluet
[   54.523042] [ 1208]   114  1208   122044       98      37       4       12             0 indicator-power
[   54.523043] [ 1209]   114  1209   132868      439      75       3        0             0 indicator-datet
[   54.523044] [ 1210]   114  1210   140272     1504     127       4        1             0 indicator-keybo
[   54.523045] [ 1211]   114  1211   134142      426      68       4        8             0 indicator-sound
[   54.523045] [ 1212]   114  1212   189042      260      47       4        0             0 indicator-sessi
[   54.523046] [ 1218]   114  1218   117391      350      89       4        0             0 indicator-appli
[   54.523047] [ 1232]     0  1232     7973       81      20       3       11             0 bluetoothd
[   54.523048] [ 1238]   114  1238   152474     1084     129       3       15             0 unity-settings-
[   54.523049] [ 1261]   114  1261   104039      719      78       4        0             0 pulseaudio
[   54.523050] [ 1272]   120  1272    45874       77      24       3        1             0 rtkit-daemon
[   54.523051] [ 1293]     0  1293    68995      324      53       3       12             0 upowerd
[   54.523052] [ 1296]   114  1296    15493      366      33       3        0             0 gconfd-2
[   54.523053] [ 1342]   110  1342    75254     1170      49       3        0             0 colord
[   54.523054] [ 1429]   113  1429    12484       98      27       3        0             0 dnsmasq
[   54.523054] [ 1430]     0  1430    12477       94      27       3        0             0 dnsmasq
[   54.523055] [ 1514]     0  1514    22408      226      49       3        0             0 sshd
[   54.523056] [ 1570]  1000  1570    11958      853      26       3        0             0 systemd
[   54.523057] [ 1571]  1000  1571    15825      501      33       3        0             0 (sd-pam)
[   54.523058] [ 1631]  1000  1631    22408      244      46       3        0             0 sshd
[   54.523058] [ 1632]  1000  1632     5779      619      16       3        0             0 bash
[   54.523059] [ 1692]   118  1692    11320       77      25       3       14             0 kerneloops
[   54.523060] [ 1745]     0  1745     3964       41      13       3        0             0 agetty
[   54.523061] [ 1768]   125  1768    13192       98      27       3        0             0 dnsmasq
[   54.523062] [ 2276]   126  2276    32160      388      58       3        0             0 exim4
[   54.523062] [ 8310]  1000  8310     5508      661      14       3        0             0 stress-ng
[   54.523063] [ 8311]  1000  8311     5508       49      13       3        0             0 stress-ng-brk
[   54.523064] [ 8312]  1000  8312     5508       46      13       3        0             0 stress-ng-brk
[   54.523065] [ 8313]  1000  8313     5508       46      13       3        0             0 stress-ng-brk
[   54.523065] [ 8314]  1000  8314     5508       46      13       3        0             0 stress-ng-brk
[   54.523066] [ 8321]  1000  8321   365871   360407     717       4        0             0 stress-ng-brk
[   54.523067] [ 8322]  1000  8322   239424   233959     470       3        0             0 stress-ng-brk
[   54.523068] [ 8323]  1000  8323   143599   138152     283       3        0             0 stress-ng-brk
[   54.523069] [ 8324]  1000  8324    54613    49145     109       3        0             0 stress-ng-brk
[   54.523070] Out of memory: Kill process 8321 (stress-ng-brk) score 363 or sacrifice child
[   54.523072] Killed process 8321 (stress-ng-brk) total-vm:1463484kB, anon-rss:1441628kB, file-rss:0kB

However, this message may have been cleared from the kernel log, so one may need to inspect the kernel logs /var/log/kern.log*

The default virtual memory setting for Linux is to over-commit memory. This means the kernel will allow one to allocate more memory than is available, allowing processes to memory map large regions because normally not all the pages in the allocation are used. However, sometimes a process will read/write to all the pages that are over committed and the kernel cannot provide enough physical memory + swap, so the OOM killer attempts to find the best candidate overcommitted process and kill it.

2 of 2
12

So, if you want to see the kernel log immediately the job is killed, wrap it with the following bash script:

#!/bin/bash
your_job_here
ret=$?
#
#  returns > 127 are a SIGNAL
#
if [ $ret -gt 127 ]; then
        sig=$((ret - 128))
        echo "Got SIGNAL sig -eq $(kill -l SIGKILL) ]; then
                echo "process was killed with SIGKILL"
                dmesg > $HOME/dmesg-kill.log
        fi
fi

Note: "your_job_here" is the name of the program/job you want to run. This script checks the return code of the program and will check if it was killed with a SIGKILL and if so, will dump the dmesg immediately afterwards to your home directory in a file called dmesg-kill.log

Hope that helps

Top answer
1 of 2
5

It definitely looks like a crypto miner malware, which has arranged a higher priority for itself and is trying to kill any commands that would kill it before they can take effect.

  │ └─809 /bin/softirq --randomx-1gb-pages -o 45.125.66.100:444 -u react -p 3cthDeQ5 --tls -o 45.94.31.89:443 -u react -p 3cthDeQ5 --tls -B

This is clearly a fake name: a real softirq process would have a name like [ksoftirqd/0] and it would have no reason to have IP addresses and ports as parameters.

Maybe you're using a weak password (use SSH key authentication for internet-accessible servers) or the software you're running has a vulnerability that allows the attacker to plant malware to the system.

In the comments, eyoung100 already identified PeerBlight (CVE-2025-55182) as the possible vulnerability, if the application is using React Server Function endpoints or React Server Components. If you are using the vulnerable versions (anything older than versions 19.0.1, 19.1.2 or 19.2.1), you'll need to update those componets before redeploying your application.

Anyway, the link in Robo's answer seems to indicate this malware is part of the RondoDox botnet.

Because the malware attempts to protect itself, you may have to stop the VPS, create a new "clean" one, and then connect the disk of the infected VPS as a secondary disk to the clean VPS to recover your data and to possibly inspect the malware. Unless you know how to check, assume any executables on the disk of the infected VPS are contaminated by malware - so don't reuse them. Before redeploying, check if the application (or any components you used in it, if the application is custom-built by yourself) for security notices and update as necessary.

2 of 2
2

It looks like you have an crypto miner malware based on XMRig running. The IP address in the command matches the IOC of this blog post: https://blog.nicter.jp/2026/01/rondodox_2026_1g/

Discussions

linux - What killed my process and why? - Stack Overflow
"Linux will give it that space, even if it is claimed by another process" That's not quite how virtual memory works... 2014-03-14T21:02:43.823Z+00:00 ... the article is quite old (2009) and not all functionality suggested in the article is in mainline. 2018-04-26T09:07:12.223Z+00:00 ... Related: How do I disable the systemd OOM process killer in Ubuntu ... More on stackoverflow.com
🌐 stackoverflow.com
ubuntu - Resume killed job - Unix & Linux Stack Exchange
I accidentally closed a terminal window where I had limited the cpu usage of a parallel job. Now, if I ps -e S in a new terminal window, I can see that job as: 311029 pts/0 TN+ 275:25 jobname ... More on unix.stackexchange.com
🌐 unix.stackexchange.com
April 1, 2022
Linux is killing a processes before it finishes, but not Windows.
Yep this is almost certainly a Python setting or possibly the aggressive OOM killer. What version of Linux are you running and which versions of Python are you using in Windows &Linux? More on reddit.com
🌐 r/linuxquestions
58
65
October 12, 2022
Latest update killed my ubuntu?

Read the link to fix the update issue....

https://github.com/Arksine/moonraker/issues/516

More on reddit.com
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4
2
October 17, 2022
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Server Fault
serverfault.com › questions › 868717 › why-was-linux-process-killed
ubuntu - Why was Linux process killed? - Server Fault
I run an ubuntu server (14.04, kernel 3.13) that has a single process serving network traffic. The process stopped running this morning and I can't figure out why. There are no SIGSEGV or out-of-m...
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Server Fault
serverfault.com › questions › 1109771 › how-to-inspect-why-my-service-process-be-killed-by-linux
ubuntu - How to inspect why my service process be killed by Linux? - Server Fault
Note that the userspace OOM killer systemd-oomd.service(8) is a more flexible solution that aims to prevent out-of-memory situations for the userspace, not just the kernel. On Linux, when memory becomes scarce to the point that the kernel has trouble allocating memory for itself, it might decide to kill a running process in order to free up memory and reduce memory pressure.
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Server Fault
serverfault.com › questions › 581390 › ubuntu-killed-process
linux - Ubuntu - killed process - Server Fault
March 11, 2014 - I'm running this command: find . -type f -delete however Ubuntu keeps killing the process. Here's the output from /var/log/syslog: Mar 11 19:54:14 hostname kernel: Killed process 29402 (find) tot...
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OneUptime
oneuptime.com › home › blog › how to kill processes by pid, name, and signal on ubuntu
How to Kill Processes by PID, Name, and Signal on Ubuntu
March 2, 2026 - Learn how to terminate processes on Ubuntu using kill, killall, and pkill by PID, name, and various signals, including when to use SIGTERM versus SIGKILL. By @nawazdhandala • Mar 02, 2026 • Reading time · Ubuntu Process Management Linux Administration Shell
Find elsewhere
🌐
Reddit
reddit.com › r/linuxquestions › linux is killing a processes before it finishes, but not windows.
r/linuxquestions on Reddit: Linux is killing a processes before it finishes, but not Windows.
October 12, 2022 -

I switched to Linux about a year ago and really dread when I have to boot into my windows machine.

However, I wrote a python script that converts a JSON file to a SQLite database. The JSON file was about 2.8gb worth of data. When I ran the script, the python loads the entire JSON into memory and then writes it to the database. (Yes, not the best way to do this task but I only needed to do it once so I did not really care to optimize for it.) On Linux the scripts runs for about 5 minuets before ending and just saying "Killed". However on windows it just keeps chugging along for about 7 minuets, then finishes the task.

Why? Why would Linux kill a running process that did not crash?

Edits: I should note that its the same computer, I have Linux and Windows dual booted.

🌐
GoLinuxCloud
golinuxcloud.com › home › how to properly kill process on ubuntu?
How to PROPERLY kill process on Ubuntu? | GoLinuxCloud
January 2, 2024 - The process to be killed is killed by typing the name of the process after the killall command. There is always an alternative in Linux. We have listed the processes with 3 different methods on the Ubuntu operating system.
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Baeldung
baeldung.com › home › processes › check what killed a linux process
Check What Killed a Linux Process | Baeldung on Linux
March 18, 2024 - SIGKILL: This special signal can’t be ignored or handled, and it immediately kills the process. In the next section, we will quickly mention SIGKILL, as this is how Linux terminates our processes when it needs to do so.
🌐
Reddit
reddit.com › r/klippers › latest update killed my ubuntu?
r/klippers on Reddit: Latest update killed my ubuntu?
October 17, 2022 -

So my setup is an old laptop and whenever i need to do something on it, i just remote desktop into it.

Earlier on today mainsail showed updates avaliable for klipper and moonraker and so i hit update. I saw it take a looong time, but i left the house while it updated. I just noticed mainsail tried to connect to moonraker with no success. and when i checked on the laptop, it was in console, (no gnome, or GUI, im not that deep into linux to remember my way around within console)

Remote desktop accepts login but then it just goes into an error screen with the only option is a button to log out.

Mainsail loads, it doesnt seem to connect to moonraker though. other services seem to be running as the laptop camera is on, my printer doesnt seem to connect to the host though (the screen doesnt start)

I dont have time to deal with it ATM, but has it happened to anybody else before or does anybody with linux experience know what to do to get things back to normal?

🌐
Pure Storage
blog.everpuredata.com › home › ways to kill ubuntu processes
Ways to Kill Ubuntu Processes | Everpure Blog
February 17, 2024 - A zombie process is one that completed its function but wasn’t removed from the process table, either due to a bug or a parent or child process that terminated abruptly without cleanup. To free up resources and terminate hung applications, you can kill the process behind it. Ubuntu is a flavor of Linux, so you can kill a process in Ubuntu using specific terminal commands that send interrupts to an application.
🌐
nixCraft
cyberciti.biz › nixcraft › howto › ubuntu linux › kill process in ubuntu linux
Kill Process In Ubuntu Linux - nixCraft
December 7, 2010 - The default signal for kill is TERM (terminate process). To list available signals, enter: $ kill -l The following are useful signals and used frequently by sys admins and Ubuntu users:
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Ask Ubuntu
askubuntu.com › questions › 1379043 › processes-consistently-getting-killed-for-no-reason-on-fresh-install-of-ubuntu-2
Processes consistently getting killed for no reason on fresh install of Ubuntu 20.04 - Ask Ubuntu
December 3, 2021 - Several applications/processes are consistently being killed for apparently no reason. Digging into it, processes are returning signal 9/terminated by SIGKILL. This should happen when memory is low...
🌐
Reddit
reddit.com › r/ubuntu › [help] ubuntu suddenly dead
r/Ubuntu on Reddit: [HELP] Ubuntu suddenly dead
March 22, 2023 - EDIT: Thank you everyone for your help (great community). This error was caused by my root partition being saturated. I followed the 16 Go recommendation though (here) , so I'm not sure why it is already full.
🌐
Reddit
reddit.com › r/linux › ubuntu 22.04's new oom killing system is killing applications (like firefox) while they're being used and it is a problem
r/linux on Reddit: Ubuntu 22.04's new OOM killing system is killing applications (like Firefox) while they're being used and it is a problem
May 27, 2022 -

So imagine yourself in this situation: you've been filling out something important in Firefox (let's say an Economics Quiz), then Firefox closes with zero explanation, while you're using it.

That happened to me, and if Canvas hasn't had an auto-save feature for quizzes, I would've lost an hour's worth of work. And it hasn't just started happening to me now either, it's been happening to me consistently ever since I upgraded from Ubuntu 20.04 to 22.04 a few weeks ago. Firefox just randomly closing on me with no explanation whatsoever. Thankfully Firefox records what tabs are open in case of a crash, but not every website has an auto-save feature, in fact, many don't.

And I can't even blame Snap for this because this has also been happening to QtCreator, a program that is decidedly not a Snap. (And it's just as annoying to lose all the files I have open in QtCreator as well, thankfully it also has an auto-save (it just doesn't record what files are open for some reason).)

Now according to this and this, it's caused by systemd-oomd. This is actually absurd because my system has been perfectly workable and not even close to frozen every time it has killed Firefox! The OOM killer should not be killing things unless it needs to and it very much didn't need to. And it's not like I have some rinky-dink laptop from 1946 either, my laptop has a full 16GB of RAM!

So let me just reiterate: Ubuntu 22.04 by default is configured to close applications while you're using them with no warning whatsoever when the system is perfectly operational. Does anyone else get how utterly asinine that is?

And I get that there are some situations where you may need to kill an application the user is using. Because the alternative may be worse, like if the system is frozen. But the system wasn't frozen, it was working fine and Ubuntu killed Firefox anyways.

I'm sure there is probably some configuration change I can make that can fix this (the AskUbuntu links mentioned increasing Swap), but that's not my point here. My point is that this is the default behavior with no warning or explanation. In no sane universe should that ever be the default.

Ubuntu wants to be the user-friendly Linux distribution right? Maybe they should start by not killing programs while the user is using them.

Thank you for reading my complaint/rant. (And apart from this major issue, Ubuntu 22.04 has actually been a pretty nice update.)

EDIT: I found more people complaining about it, so I'm not alone in thinking that this default is stupid.

EDIT 2: Someone reported this as a bug on Ubuntu's bug tracker: https://bugs.launchpad.net/ubuntu/+source/systemd/+bug/1972159.

🌐
Reddit
reddit.com › r/ubuntu › ubuntu 22.04's new oom killing system is killing applications (like firefox) while they're being used and it is a problem
r/Ubuntu on Reddit: Ubuntu 22.04's new OOM killing system is killing applications (like Firefox) while they're being used and it is a problem
May 27, 2022 -

So imagine yourself in this situation: you've been filling out something important in Firefox (let's say an Economics Quiz), then Firefox closes with zero explanation, while you're using it.

That happened to me, and if Canvas hasn't had an auto-save feature for quizzes, I would've lost an hour's worth of work. And it hasn't just started happening to me now either, it's been happening to me consistently ever since I upgraded from Ubuntu 20.04 to 22.04 a few weeks ago. Firefox just randomly closing on me with no explanation whatsoever. Thankfully Firefox records what tabs are open in case of a crash, but not every website has an auto-save feature, in fact, many don't.

And I can't even blame Snap for this because this has also been happening to QtCreator, a program that is decidedly not a Snap. (And it's just as annoying to lose all the files I have open in QtCreator as well, thankfully it also has an auto-save (it just doesn't record what files are open for some reason).)

Now according to this and this, it's caused by systemd-oomd. This is actually absurd because my system has been perfectly workable and not even close to frozen every time it has killed Firefox! The OOM killer should not be killing things unless it needs to and it very much didn't need to. And it's not like I have some rinky-dink laptop from 1946 either, my laptop has a full 16GB of RAM!

So let me just reiterate: Ubuntu 22.04 by default is configured to close applications while you're using them with no warning whatsoever when the system is perfectly operational. Does anyone else get how utterly asinine that is?

And I get that there are some situations where you may need to kill an application the user is using. Because the alternative may be worse, like if the system is frozen. But the system wasn't frozen, it was working fine and Ubuntu killed Firefox anyways.

I'm sure there is probably some configuration change I can make that can fix this (the AskUbuntu links mentioned increasing Swap), but that's not my point here. My point is that this is the default behavior with no warning or explanation. In no sane universe should that ever be the default.

Ubuntu wants to be the user-friendly Linux distribution right? Maybe they should start by not killing programs while the user is using them.

Thank you for reading my complaint/rant. (And apart from this major issue, Ubuntu 22.04 has actually been a pretty nice update.)

EDIT: I found more people complaining about it, so I'm not alone in thinking that this default is stupid.

EDIT 2: Someone reported this as a bug on Ubuntu's bug tracker: https://bugs.launchpad.net/ubuntu/+source/systemd/+bug/1972159.

Top answer
1 of 5
25
lol @ the link in your edit. guy has a problem, responses are just "mAkE lArGeR sWaP fIlE n00b" and when user explains they have thirty-two GIGABYTES OF RAM INSTALLED IN THEIR MACHINE responses are "oh, well uh... you didn't try my solution, so we'll never know if low RAM/small swap file was the issue, it's your decision to cripple your system instead of letting OOM do its job", they just completely cannot see this dude's problem past their own damn noses and just repeat the same solution to users even when said solution is infeasible/will not help (i mean, come on, thirty-two gb, and all they want to do is run a compiler to, yknow, compile some apps that they're developing. "increase swap file size from 2 gb to 4 gb" is literally irrelevant here because this dude has plenty enough RAM to start with and shouldn't be hitting the usage limit when running applications like compilers.) i'm serious, look at the comments on the last answer.
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19
If Firefox exceeds whatever memory usage or pressure thresholds Ubuntu has configured, oomd will kill the process. Memory pressure is not the raw amount of memory used. It's what it sounds like: the amount of overall strain a process is putting on the system memory. Oomd killing processes before the system freezes is its whole job. If the system is frozen, it's too late to do anything to recover it while the kernel is having a fit. So, when memory usage and/or pressure reaches some distro-configured limits, it'll start killing before the situation gets bad enough to cause freezes. Of course, if oomd is misconfigured and is set up too aggressively, then that's an issue. Or perhaps Firefox really was using a lot of memory and the system did its job before it completely died? Do you have a swap partition?