On 22.04, I saw similar issue after a few apt upgrade, which trigger zsys service etc. the zsysd will consume much more memory than it should do. and no response when apt requesting. here is a typical result: root@zymElite:~# apt-get update;apt-get dist-upgrade Hit:1 http://dl.google.com/linux/chrome/deb stable InRelease Hit:2 http://packages.microsoft.com/repos/edge stable InRelease Hit:3 http://archive.ubuntu.com/ubuntu jammy InRelease Get:4 http://archive.ubuntu.com/ubuntu jammy-updates InRelease [109 kB] Hit:5 https://ppa.launchpadcontent.net/agornostal/ulauncher/ubuntu jammy InRelease Get:6 http://archive.ubuntu.com/ubuntu jammy-backports InRelease [99.8 kB] Get:7 http://archive.ubuntu.com/ubuntu jammy-security InRelease [110 kB] Get:8 http://archive.ubuntu.com/ubuntu jammy-updates/main amd64 Packages [277 kB] Get:9 http://archive.ubuntu.com/ubuntu jammy-updates/main i386 Packages [124 kB] Get:10 http://archive.ubuntu.com/ubuntu jammy-updates/main amd64 DEP-11 Metadata [73.4 kB] Get:11 http://archive.ubuntu.com/ubuntu jammy-updates/universe i386 Packages [46.3 kB] Get:12 http://archive.ubuntu.com/ubuntu jammy-updates/universe amd64 Packages [116 kB] Get:13 http://archive.ubuntu.com/ubuntu jammy-updates/universe Translation-en [40.1 kB] Get:14 http://archive.ubuntu.com/ubuntu jammy-updates/universe amd64 DEP-11 Metadata [92.0 kB] Get:15 http://archive.ubuntu.com/ubuntu jammy-updates/universe amd64 c-n-f Metadata [2,344 B] Get:16 http://archive.ubuntu.com/ubuntu jammy-backports/universe amd64 DEP-11 Metadata [1,192 B] Get:17 http://archive.ubuntu.com/ubuntu jammy-security/main amd64 DEP-11 Metadata [11.4 kB] Get:18 http://archive.ubuntu.com/ubuntu jammy-security/universe amd64 c-n-f Metadata [1,128 B] Fetched 1,104 kB in 5s (229 kB/s) Reading package lists... Done Reading package lists... Done Building dependency tree... Done Reading state information... Done Calculating upgrade... Done The following packages will be upgraded: deja-dup 1 upgraded, 0 newly installed, 0 to remove and 0 not upgraded. Need to get 298 kB of archives. After this operation, 8,192 B of additional disk space will be used. Do you want to continue? [Y/n] Get:1 http://archive.ubuntu.com/ubuntu jammy-updates/main amd64 deja-dup amd64 42.9-1ubuntu3 [298 kB] Fetched 298 kB in 2s (149 kB/s) ERROR Service took too long to respond. Disconnecting client. (Reading database ... 288053 files and directories currently installed.) Preparing to unpack .../deja-dup_42.9-1ubuntu3_amd64.deb ... Unpacking deja-dup (42.9-1ubuntu3) over (42.9-1ubuntu2) ... Setting up deja-dup (42.9-1ubuntu3) ... Processing triggers for desktop-file-utils (0.26-1ubuntu3) ... Processing triggers for hicolor-icon-theme (0.17-2) ... Processing triggers for gnome-menus (3.36.0-1ubuntu3) ... Processing triggers for libglib2.0-0:amd64 (2.72.1-1) ... Processing triggers for libglib2.0-0:i386 (2.72.1-1) ... Processing triggers for man-db (2.10.2-1) ... Processing triggers for mailcap (3.70+nmu1ubuntu1) ... ERROR Service took too long to respond. Disconnecting client. the htop show zsysd used about 3G RES memory. here is the /proc/status: zym@zymElite:~$ cat /proc/3757/status Name: zsysd Umask: 0022 State: S (sleeping) Tgid: 3757 Ngid: 0 Pid: 3757 PPid: 1 TracerPid: 0 Uid: 0 0 0 0 Gid: 0 0 0 0 FDSize: 128 Groups: NStgid: 3757 NSpid: 3757 NSpgid: 3757 NSsid: 3757 VmPeak: 5643412 kB VmSize: 5643412 kB VmLck: 0 kB VmPin: 0 kB VmHWM: 3298728 kB VmRSS: 3298728 kB RssAnon: 3291108 kB RssFile: 7620 kB RssShmem: 0 kB VmData: 3542848 kB VmStk: 132 kB VmExe: 5000 kB VmLib: 6324 kB VmPTE: 6784 kB VmSwap: 0 kB HugetlbPages: 0 kB CoreDumping: 0 THP_enabled: 1 Threads: 23 SigQ: 1/254061 SigPnd: 0000000000000000 ShdPnd: 0000000000000000 SigBlk: 0000000000000000 SigIgn: 0000000000000000 SigCgt: fffffffd7fc1feff CapInh: 0000000000000000 CapPrm: 000001ffffffffff CapEff: 000001ffffffffff CapBnd: 000001ffffffffff CapAmb: 0000000000000000 NoNewPrivs: 1 Seccomp: 0 Seccomp_filters: 0 Speculation_Store_Bypass: thread vulnerable SpeculationIndirectBranch: conditional enabled Cpus_allowed: ffff Cpus_allowed_list: 0-15 Mems_allowed: 00000000,00000000,00000000,00000000,00000000,00000000,00000000,00000000,00000000,00000000,00000000,00000000,00000000,00000000,00000000,00000000,00000000,00000000,00000000,00000000,00000000,00000000,00000000,00000000,00000000,00000000,00000000,00000000,00000000,00000000,00000000,00000001 Mems_allowed_list: 0 voluntary_ctxt_switches: 89474 nonvoluntary_ctxt_switches: 63785 I think that zsysd may have very serious memory issue which will not func well in most case. So as other issues, we can see many with similar memory problem. my case: 2TB zfs root, nearly half full. if you need my zfs status, please let me know.