Debian Bullseye 服务器使用了几乎 100% 的 RAM 数量 (7.65G / 7.79 G)：
但没有内存使用率超过 0.0% 的进程
DEV root@postgres2 ~# free -h
total used free shared buff/cache available
Mem: 7.8Gi 7.7Gi 100Mi 0.0Ki 42Mi 39Mi
Swap: 14Gi 767Mi 14Gi
DEV root@postgres2 ~# ps -eo pid,ppid,cmd,comm,%mem,%cpu --sort=-%mem | head -10
PID PPID CMD COMMAND %MEM %CPU
7072 1 /usr/bin/apt-get -o Debug:: apt-get 0.0 11.9
8424 1 /usr/bin/apt-get -o Debug:: apt-get 0.0 7.8
7252 1 /usr/bin/apt-get -o Debug:: apt-get 0.0 11.0
8265 1 /usr/bin/apt-get -o Debug:: apt-get 0.0 8.3
8085 1 /usr/bin/apt-get -o Debug:: apt-get 0.0 8.6
9806 22518 postgres: 12/main: repmgr r postgres 0.0 13.0
9703 1 /usr/bin/apt-get -o Debug:: apt-get 0.0 5.2
206 1 /lib/systemd/systemd-journa systemd-journal 0.0 0.0
9814 5382 ps -eo pid,ppid,cmd,comm,%m ps 0.0 0.0
我没有运行那么多进程：
DEV root@postgres2 ~# ps ax|wc -l
224
全部内存使用量：
DEV root@postgres2 ~# cat /proc/meminfo
MemTotal: 8170216 kB
MemFree: 131976 kB
MemAvailable: 42600 kB
Buffers: 7000 kB
Cached: 55200 kB
SwapCached: 52900 kB
Active: 82772 kB
Inactive: 73988 kB
Active(anon): 48652 kB
Inactive(anon): 49300 kB
Active(file): 34120 kB
Inactive(file): 24688 kB
Unevictable: 0 kB
Mlocked: 0 kB
SwapTotal: 15622140 kB
SwapFree: 15211964 kB
Dirty: 68 kB
Writeback: 0 kB
AnonPages: 92920 kB
Mapped: 33280 kB
Shmem: 3340 kB
Slab: 7808800 kB
SReclaimable: 36480 kB
SUnreclaim: 7772320 kB
KernelStack: 3616 kB
PageTables: 14860 kB
NFS_Unstable: 0 kB
Bounce: 0 kB
WritebackTmp: 0 kB
CommitLimit: 19707248 kB
Committed_AS: 1162964 kB
VmallocTotal: 34359738367 kB
VmallocUsed: 0 kB
VmallocChunk: 0 kB
Percpu: 1288 kB
HardwareCorrupted: 0 kB
AnonHugePages: 6144 kB
ShmemHugePages: 0 kB
ShmemPmdMapped: 0 kB
HugePages_Total: 0
HugePages_Free: 0
HugePages_Rsvd: 0
HugePages_Surp: 0
Hugepagesize: 2048 kB
Hugetlb: 0 kB
DirectMap4k: 5609320 kB
DirectMap2M: 2779136 kB
DEV root@postgres2 ~# ps aux --sort -rss | head -n15
USER PID %CPU %MEM VSZ RSS TTY STAT START TIME COMMAND
root 381 0.0 0.8 1694928 68916 ? Ssl 2022 44:28 /usr/share/auditbeat/bin/auditbeat --environment systemd -c /etc/auditbeat/auditbeat.yml --path.home /usr/share/auditbeat --path.config /etc/auditbeat --path.data /var/lib/auditbeat --path.logs /var/log/auditbeat
root 380 0.0 0.1 1373392 12796 ? Ssl 2022 9:33 /usr/share/metricbeat/bin/metricbeat --environment systemd -c /etc/metricbeat/metricbeat.yml --path.home /usr/share/metricbeat --path.config /etc/metricbeat --path.data /var/lib/metricbeat --path.logs /var/log/metricbeat
nagios 1257 0.0 0.0 1056796 6756 ? Sl 2022 22:49 /usr/lib/x86_64-linux-gnu/icinga2/sbin/icinga2 --no-stack-rlimit daemon --close-stdio -e /var/log/icinga2/error.log
root 23205 0.0 0.0 159992 5004 pts/0 S 16:00 0:00 fish
root 23273 0.0 0.0 10960 3348 pts/0 R+ 16:00 0:00 ps aux --sort -rss
root 211 0.0 0.0 81564 2600 ? Ss 2022 16:31 /lib/systemd/systemd-journald
root 1 0.0 0.0 170780 2596 ? Ss 2022 3:11 /sbin/init
nagios 1262 0.0 0.0 259476 2268 ? S 2022 6:05 /usr/lib/x86_64-linux-gnu/icinga2/sbin/icinga2 --no-stack-rlimit daemon --close-stdio -e /var/log/icinga2/error.log
me 23170 0.0 0.0 159752 1828 pts/0 Ss 16:00 0:00 -fish
me 23153 0.0 0.0 21164 1744 ? Ss 16:00 0:00 /lib/systemd/systemd --user
postgres 23984 0.0 0.0 219008 1572 ? Ss 2022 15:22 /usr/lib/postgresql/12/bin/postgres -D /var/lib/postgresql/12/main -c config_file=/etc/postgresql/12/main/postgresql.conf
root 23141 0.0 0.0 16616 1528 ? Ss 16:00 0:00 sshd: me**strong text** [priv]
Debian-+ 382 0.0 0.0 42988 1428 ? Ss 2022 11:50 /usr/sbin/snmpd -Lsd -Lf /dev/null -u Debian-snmp -g Debian-snmp -I -smux mteTrigger mteTriggerConf -f -p /run/snmpd.pid
postgres 21836 0.0 0.0 220064 1312 ? Ss 15:51 0:00 postgres: 12/main: mydb mydb 192.168.100.33(52436) idle
我该如何处理才能了解发生了什么事？