-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 On Monday, 2018-10-15 at 14:54 +0200, Per Jessen wrote:

Carlos E. R. wrote:

...

I'm trying to force the clamd process to swap agresively, because by default it eats 500 MB of my limited memory even when it is doing nothing but waiting.

Be aware this will increase email processing time, otherwise it ought to work fine.

That's fine. Swapping out is not immediate, so if there is a continuous flow of mails it should not swap. A delay of a fraction of a second when sending a single email is not important.

...

Apparently this is done with cgroups, about which I know close to nothing.

Search the list for an example in the last couple of weeks. I can't remember who it was, but one process was gobbling up too much memory, rendering the entire system unworkable. The issue was solved by setting a memory limit using cgroups.

Limiting memory would probably make the process to crash, I suppose. Probably this one: Date: Wed, 19 Sep 2018 12:21:11 +0100 From: Peter Suetterlin <> To: "opensuse@opensuse.org" Subject: Re: [opensuse] swap performance ... I even participated on that thread, then I forgot. He does: sudo mkdir /sys/fs/cgroup/memory/notover4g echo 4294967296 | sudo tee /sys/fs/cgroup/memory/notover4g/memory.limit_in_bytes > /dev/null echo "$$" | sudo tee /sys/fs/cgroup/memory/notover4g/cgroup.procs > /dev/null Ah! So creating the directory is the trick! Telcontar:/sys/fs/cgroup/memory # ls clamd/ cgroup.clone_children cgroup.procs memory.force_empty memory.low_limit_in_bytes memory.move_charge_at_immigrate memory.oom_control memory.soft_limit_in_bytes memory.swappiness memory.use_hierarchy tasks cgroup.event_control memory.failcnt memory.limit_in_bytes memory.max_usage_in_bytes memory.numa_stat memory.pressure_level memory.stat memory.usage_in_bytes notify_on_release Telcontar:/sys/fs/cgroup/memory # Telcontar:/sys/fs/cgroup/memory # cd clamd/ Telcontar:/sys/fs/cgroup/memory/clamd # ls cgroup.clone_children cgroup.procs memory.force_empty memory.low_limit_in_bytes memory.move_charge_at_immigrate memory.oom_control memory.soft_limit_in_bytes memory.swappiness memory.use_hierarchy tasks cgroup.event_control memory.failcnt memory.limit_in_bytes memory.max_usage_in_bytes memory.numa_stat memory.pressure_level memory.stat memory.usage_in_bytes notify_on_release Telcontar:/sys/fs/cgroup/memory/clamd # cat memory.swappiness 60 Telcontar:/sys/fs/cgroup/memory/clamd # echo 100 > memory.swappiness Telcontar:/sys/fs/cgroup/memory/clamd # cat memory.swappiness 100 Telcontar:/sys/fs/cgroup/memory/clamd # Still the process is not swapped out. I'll restart the process. [...] No, not swapped. But at least now I know how to change swapiness of a single process, thanks! :-) Ah! I *notice* more in the thread! He did explain the process entirely in another post. «Then start a process, get it's PID and echo $PID > /sys/fs/cgroup/memory/14G/cgroup.procs» Ok... let's see. Telcontar:/sys/fs/cgroup/memory/clamd # echo 100 > memory.swappiness Telcontar:/sys/fs/cgroup/memory/clamd # cat cgroup.procs Telcontar:/sys/fs/cgroup/memory/clamd # echo 16284 > cgroup.procs Telcontar:/sys/fs/cgroup/memory/clamd # cat cgroup.procs 16284 Telcontar:/sys/fs/cgroup/memory/clamd # Telcontar:/sys/fs/cgroup/memory/clamd # cat tasks 16284 16285 Telcontar:/sys/fs/cgroup/memory/clamd # But still does not swap out anything. top - 15:36:30 up 7 days, 1:29, 1 user, load average: 0,76, 0,71, 0,72 Tasks: 531 total, 1 running, 529 sleeping, 0 stopped, 1 zombie %Cpu(s): 12,0 us, 3,1 sy, 0,0 ni, 75,5 id, 9,3 wa, 0,0 hi, 0,1 si, 0,0 st KiB Mem: 8174528 total, 7674028 used, 500500 free, 18516 buffers KiB Swap: 25165820 total, 5125572 used, 20040248 free. 1780272 cached Mem PID USER PR NI VIRT RES SHR SWAP S %CPU %MEM TIME+ COMMAND 7098 cer 20 0 4340104 1,534g 58612 388588 S 0,330 19,67 306:21.50 thunderbird-bin 7494 cer 20 0 3080508 845212 67024 255556 S 15,18 10,34 159:22.82 Web Content 5221 cer 20 0 10,116g 670840 136600 462136 S 18,48 8,206 137:51.72 firefox 7341 cer 20 0 2892228 660472 37464 202260 S 0,330 8,080 78:58.07 Web Content 16284 vscan 20 0 784860 554400 3508 0 S 0,000 6,782 0:00.01 clamd . . . . . . . . . . . . . . . . . . . . . .******* Limiting the memory is not what I want, because it would limit the memory while the process is actually working and needing the memory, thus trashing.

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Oct 15 14:08:49 Telcontar systemd[1]: [/etc/systemd/system/clamd.service.d/override.conf:2] Unknown lvalue ['ControlGroupAttribute' in section 'Service' Telcontar:~ #

What? The lvalue is copied from the documentation! How can I then do it?

The option was removed: https://bugzilla.redhat.com/show_bug.cgi?id=1172890

Damm! :-/ Lukáš Nykrýn 2014-12-11 01:35:42 EST This option was removed in 208 - From 208 release notes: * As discussed earlier, the low-level cgroup configuration options ControlGroup=, ControlGroupModify=, ControlGroupPersistent=, ControlGroupAttribute= have been removed. Please use high-level attribute settings instead as well as slice units. And some other info http://lwn.net/Articles/555923/ But what "high-level attribute setting"? The link does not explain. Those entries were used when the high-level attributes do not exist - so says the doc. Where are they listed, if the documentation is incorrect? - -- Cheers, Carlos E. R. (from openSUSE 42.3 x86_64 "Malachite" at Telcontar) -----BEGIN PGP SIGNATURE----- Version: GnuPG v2 iEYEARECAAYFAlvEme8ACgkQtTMYHG2NR9XG8wCeJnEGyQ79gRWjSqLA8ql0vxzD 78MAoIXsdX/G5/Mhf+w8QA6FrKELEDT9 =+TsZ -----END PGP SIGNATURE-----

-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 On Monday, 2018-10-15 at 20:50 +0200, Carlos E. R. wrote:

On Monday, 2018-10-15 at 15:45 +0200, Carlos E. R. wrote:

...

...

But still does not swap out anything.

It does now. Not as much as I would like, though.

...

top - 15:36:30 up 7 days, 1:29, 1 user, load average: 0,76, 0,71, 0,72 Tasks: 531 total, 1 running, 529 sleeping, 0 stopped, 1 zombie % Cpu(s): 12,0 us, 3,1 sy, 0,0 ni, 75,5 id, 9,3 wa, 0,0 hi, 0,1 si, % 0,0 % st KiB Mem: 8174528 total, 7674028 used, 500500 free, 18516 buffers KiB Swap: 25165820 total, 5125572 used, 20040248 free. 1780272 cached Mem

PID USER PR NI VIRT RES SHR SWAP S %CPU %MEM TIME+ COMMAND 7098 cer 20 0 4340104 1,534g 58612 388588 S 0,330 19,67 306:21.50 thunderbird-bin 7494 cer 20 0 3080508 845212 67024 255556 S 15,18 10,34 159:22.82 Web Content 5221 cer 20 0 10,116g 670840 136600 462136 S 18,48 8,206 137:51.72 firefox 7341 cer 20 0 2892228 660472 37464 202260 S 0,330 8,080 78:58.07 Web Content 16284 vscan 20 0 784860 554400 3508 0 S 0,000 6,782 0:00.01 clamd . . . . . . . . . . . . . . . . . . . . . .*******

16284 vscan 20 0 785012 208696 3296 345896 S 0,000 2,553 0:14.70 clamd

That's with memory.swappiness = 99. I'll try 100 now. Notice that the TIME+ is now used, so some automatic emails were sent, or its database was updated.

with 100, after a while: 16284 vscan 20 0 785012 107380 3244 447160 S 0,000 1,314 0:14.73 clamd Much better :-) Next step: automatize init. - -- Cheers, Carlos E. R. (from openSUSE 42.3 x86_64 "Malachite" at Telcontar) -----BEGIN PGP SIGNATURE----- Version: GnuPG v2 iEYEARECAAYFAlvE5C0ACgkQtTMYHG2NR9WtpACdGtcGIDlN3ouh9blczpIHjOft NJUAnA+AdvyyeK18C/7Ye4LrURgUwKup =qTKD -----END PGP SIGNATURE----- -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse+owner@opensuse.org

On 10/15/2018 03:56 PM, Carlos E. R. wrote:

and improving:

16284 vscan 20 0 785012 43892 3084 510488 S 0,000 0,537 0:14.87 clamd

I wonder why it took so long to swap it out :-?

Did you try echoing 100 > /proc/sys/vm/swappiness directly? It should respect the /etc/sysctl.d/99-sysctl.conf vm.swappiness config option, but I'm not sure when that is re-read on change. -- David C. Rankin, J.D.,P.E.

-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 On Monday, 2018-10-15 at 15:45 +0200, Carlos E. R. wrote:

On Monday, 2018-10-15 at 14:54 +0200, Per Jessen wrote:

...

Carlos E. R. wrote:

...

I'm trying to force the clamd process to swap agresively, because by default it eats 500 MB of my limited memory even when it is doing nothing but waiting.

...

...

...

Apparently this is done with cgroups, about which I know close to nothing.

Search the list for an example in the last couple of weeks. I can't remember who it was, but one process was gobbling up too much memory, rendering the entire system unworkable. The issue was solved by setting a memory limit using cgroups.

...

Limiting memory would probably make the process to crash, I suppose.

Probably this one:

Date: Wed, 19 Sep 2018 12:21:11 +0100 From: Peter Suetterlin <> To: "opensuse@opensuse.org" Subject: Re: [opensuse] swap performance

...

Ok, so I created a clamd cgroup to adjust its memory.swappiness to 100, and that works. It is not swaped out fast. Now I have edited "/usr/lib/systemd/system/clamd.service" thus: [Unit] Description=Clamav antivirus Deamon After=syslog.target network.target [Service] Type=forking ExecStartPre=/bin/sh -c "mkdir /sys/fs/cgroup/memory/clamd" ExecStartPre=/bin/sh -c "echo 100 > /sys/fs/cgroup/memory/clamd/memory.swappiness" ExecStart=/usr/sbin/clamd ExecStartPost=/bin/sh -c "echo $MAINPID > /sys/fs/cgroup/memory/clamd/cgroup.procs" ;User=vscan ;Group=vscan ;PrivateTmp=yes ExecStopPost=/bin/sh -c "rmdir /sys/fs/cgroup/memory/clamd" [Install] WantedBy=multi-user.target :-) Maybe I can move the modifications to "/etc/systemd/system/clamd.service.d/override.conf" instead. :-? - -- Cheers, Carlos E. R. (from openSUSE 42.3 x86_64 "Malachite" at Telcontar) -----BEGIN PGP SIGNATURE----- Version: GnuPG v2 iEYEARECAAYFAlwBRdYACgkQtTMYHG2NR9WIGgCcDv+ZwgGBdc7XA2mK5jjMxkRa JbMAniRyMVYqbvkWZsejz+nE2RVuFZjn =NstW -----END PGP SIGNATURE----- -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse+owner@opensuse.org