Re: [qubes-users] Re: High dom0 CPU usage by qubesd
Although my implementation is not fully complete, I have decided to share my progress: https://github.com/v6ak/qubes-i3status-dir It is available under a WTFPL-like license. Regards, Vít Šesták 'v6ak' On Monday, January 18, 2021 at 2:39:09 PM UTC+1 Vít Šesták wrote: > BTW, I've started the reimplementation of qubes-i3status as a Python > wrapper around i3status. I am trying to be quite conservative – in the > default settings, there should be no visible difference except CPU load, > periodic freezes and bug fixes (battery status). > > * Some indicators (battery, load and time) are already present, they just > need some adjustments of the format in order to be a drop-in replacement. > * Disk status was easy to implement. I just need to verify that it can > properly handle the change of default pool. > * Running qubes: I need to study the events deeper… > * NetVM status – currently, it is disabled and discouraged. I might decide > to reimplement this, but I am not 100% sure right now. > > Regards, > Vít Šesták 'v6ak' > > On Friday, January 15, 2021 at 5:40:38 PM UTC+1 David Hobach wrote: > >> Hi Vit, >> >> > * I have many VMs in my computer. >> > * I use i3 with qubes-i3status >> > * The script qubes-i3status calls command qvm-ls --no-spinner >> --raw-data >> > --fields NAME,FLAGS quite frequently. >> > * The command qvm-ls --no-spinner --raw-data --fields NAME,FLAGS seems >> to >> > cause high CPU load. Unfortunately, the process that shows the high CPU >> > usage is qubesd, not qvm-ls. >> > >> > What can be improved: >> > >> > a. Don't use qubes-i3status. Problem solved. >> > b. Optimize qvm-ls. Not sure how hard it is. >> >> This issue is really old (back from at least 3.2) and caused by each >> qvm-ls line relating to one request to qubesd. Actually it was even worse >> with 3.2. >> >> It should improve with 4.1 though, see [1]. >> >> [1] https://github.com/QubesOS/qubes-issues/issues/3293 >> >> > c. Optimize qubes-i3status. I am not sure about the ideal way of doing >> > that, but clearly running qvm-ls --no-spinner --raw-data --fields >> > NAME,FLAGS just to compute the number of running qubes is far from >> optimal. >> > One could add --running. And maybe it could have been written without >> > flags. The script just ignores VMs with the first flag being “0” (maybe >> in >> > order to ignore dom0) and the second flag being “r” (probably not >> needed >> > with --running). >> >> Filtering might work in the meantime, yes. >> >> BR >> David >> >> -- You received this message because you are subscribed to the Google Groups "qubes-users" group. To unsubscribe from this group and stop receiving emails from it, send an email to qubes-users+unsubscr...@googlegroups.com. To view this discussion on the web visit https://groups.google.com/d/msgid/qubes-users/b98004f9-01be-447c-9388-65944f948a14n%40googlegroups.com.
Re: [qubes-users] Re: High dom0 CPU usage by qubesd
BTW, I've started the reimplementation of qubes-i3status as a Python wrapper around i3status. I am trying to be quite conservative – in the default settings, there should be no visible difference except CPU load, periodic freezes and bug fixes (battery status). * Some indicators (battery, load and time) are already present, they just need some adjustments of the format in order to be a drop-in replacement. * Disk status was easy to implement. I just need to verify that it can properly handle the change of default pool. * Running qubes: I need to study the events deeper… * NetVM status – currently, it is disabled and discouraged. I might decide to reimplement this, but I am not 100% sure right now. Regards, Vít Šesták 'v6ak' On Friday, January 15, 2021 at 5:40:38 PM UTC+1 David Hobach wrote: > Hi Vit, > > > * I have many VMs in my computer. > > * I use i3 with qubes-i3status > > * The script qubes-i3status calls command qvm-ls --no-spinner --raw-data > > --fields NAME,FLAGS quite frequently. > > * The command qvm-ls --no-spinner --raw-data --fields NAME,FLAGS seems to > > cause high CPU load. Unfortunately, the process that shows the high CPU > > usage is qubesd, not qvm-ls. > > > > What can be improved: > > > > a. Don't use qubes-i3status. Problem solved. > > b. Optimize qvm-ls. Not sure how hard it is. > > This issue is really old (back from at least 3.2) and caused by each > qvm-ls line relating to one request to qubesd. Actually it was even worse > with 3.2. > > It should improve with 4.1 though, see [1]. > > [1] https://github.com/QubesOS/qubes-issues/issues/3293 > > > c. Optimize qubes-i3status. I am not sure about the ideal way of doing > > that, but clearly running qvm-ls --no-spinner --raw-data --fields > > NAME,FLAGS just to compute the number of running qubes is far from > optimal. > > One could add --running. And maybe it could have been written without > > flags. The script just ignores VMs with the first flag being “0” (maybe > in > > order to ignore dom0) and the second flag being “r” (probably not needed > > with --running). > > Filtering might work in the meantime, yes. > > BR > David > > -- You received this message because you are subscribed to the Google Groups "qubes-users" group. To unsubscribe from this group and stop receiving emails from it, send an email to qubes-users+unsubscr...@googlegroups.com. To view this discussion on the web visit https://groups.google.com/d/msgid/qubes-users/42dba1a7-e551-46fa-98e1-d8d59d5356f7n%40googlegroups.com.
Re: [qubes-users] Re: High dom0 CPU usage by qubesd
Hi Vit, * I have many VMs in my computer. * I use i3 with qubes-i3status * The script qubes-i3status calls command qvm-ls --no-spinner --raw-data --fields NAME,FLAGS quite frequently. * The command qvm-ls --no-spinner --raw-data --fields NAME,FLAGS seems to cause high CPU load. Unfortunately, the process that shows the high CPU usage is qubesd, not qvm-ls. What can be improved: a. Don't use qubes-i3status. Problem solved. b. Optimize qvm-ls. Not sure how hard it is. This issue is really old (back from at least 3.2) and caused by each qvm-ls line relating to one request to qubesd. Actually it was even worse with 3.2. It should improve with 4.1 though, see [1]. [1] https://github.com/QubesOS/qubes-issues/issues/3293 c. Optimize qubes-i3status. I am not sure about the ideal way of doing that, but clearly running qvm-ls --no-spinner --raw-data --fields NAME,FLAGS just to compute the number of running qubes is far from optimal. One could add --running. And maybe it could have been written without flags. The script just ignores VMs with the first flag being “0” (maybe in order to ignore dom0) and the second flag being “r” (probably not needed with --running). Filtering might work in the meantime, yes. BR David -- You received this message because you are subscribed to the Google Groups "qubes-users" group. To unsubscribe from this group and stop receiving emails from it, send an email to qubes-users+unsubscr...@googlegroups.com. To view this discussion on the web visit https://groups.google.com/d/msgid/qubes-users/e8acbeda-199a-8e1f-1a94-caaa0b4bb120%40hackingthe.net. smime.p7s Description: S/MIME Cryptographic Signature
Re: [qubes-users] Re: High dom0 CPU usage by qubesd
OK, reported, some optimization attempts included: https://groups.google.com/g/qubes-users/c/uTi3QHuhdy8 Also, I have some temptation to reimplement qubes-i3status as a Python wrapper around the original i3status. We would probably also resolve some other problems. For example, I had to fix reading of the battery status. BTW, if you have ~25% CPU load, I guess you just have quad-core CPU (or maybe dual-core with hyperthreading). Regards, Vít Šesták 'v6ak' On Wednesday, January 6, 2021 at 11:34:42 AM UTC+1 Jarrah wrote: > This is some really nice tracing work. I'm sure it would be appreciated > as an issue in the qubes-issues repository so it can be tracked properly. > > While I haven't gone to the same depth, I can confirm that `qubesd` > jumps to ~25% CPU regularly on my (albeit much beefier) system with i3. > This does correlate with qubes-i3status running on my system as well. > > > As a temporary work around, you could modify the script > (/usr/bin/qubes-i3status:123) to run every minute or longer. This would > have the downside of the clock updating slower, but otherwise should not > be a problem. > > Alternatively, if the number of running VMs doesn't interest you, you > could comment out line 113 and modify 122 to suit this. > > -- You received this message because you are subscribed to the Google Groups "qubes-users" group. To unsubscribe from this group and stop receiving emails from it, send an email to qubes-users+unsubscr...@googlegroups.com. To view this discussion on the web visit https://groups.google.com/d/msgid/qubes-users/e3bcfe4b-2127-4d94-a3d0-07871ffbaf37n%40googlegroups.com.
Re: [qubes-users] Re: High dom0 CPU usage by qubesd
This is some really nice tracing work. I'm sure it would be appreciated as an issue in the qubes-issues repository so it can be tracked properly. While I haven't gone to the same depth, I can confirm that `qubesd` jumps to ~25% CPU regularly on my (albeit much beefier) system with i3. This does correlate with qubes-i3status running on my system as well. As a temporary work around, you could modify the script (/usr/bin/qubes-i3status:123) to run every minute or longer. This would have the downside of the clock updating slower, but otherwise should not be a problem. Alternatively, if the number of running VMs doesn't interest you, you could comment out line 113 and modify 122 to suit this. -- You received this message because you are subscribed to the Google Groups "qubes-users" group. To unsubscribe from this group and stop receiving emails from it, send an email to qubes-users+unsubscr...@googlegroups.com. To view this discussion on the web visit https://groups.google.com/d/msgid/qubes-users/47a92b74-22ad-276b-8c81-05dc9970dfe0%40undef.tools.
[qubes-users] Re: High dom0 CPU usage by qubesd
Hi,
I have some further info. I partially know cause and have a workaround.
There is my investigation. Some minor inaccuracies might be caused by
retrospective writing:
1. I have tried to debug using strace. (Prerequisite: sudo
qubes-dom0-install strace) After finding pid of qubesd, I ran:
sudo strace -s 256 -p PID_OF_QUBESD -o /tmp/qubesd.log
It looks like few seconds is enough to get a reasonable sample, see below.
2. I ran sort /tmp/qubesd.log | uniq -c | sort -n (one can also add “ -r |
head -n 50”).
I have noticed an interesting line that repeats frequently:
sendto(270, "QubesNoSuchPropertyError\0", 25, 0, NULL, 0) = 25
3. Look closer:
$ grep --before=5 --after=5 QubesNoSuchPropertyError /tmp/qubesd.log
The output contains many repeated occurrences of this, just with a
different VM name. It seems to iterate over all the VMs (even those that
are not running):
--
epoll_wait(3, [], , 0)= 0
getpid()=
epoll_wait(3, [], , 0)= 0
epoll_wait(3, [], , 0)= 0
sendto(, "2\0", 2, 0, NULL, 0) = 2
sendto(, "QubesNoSuchPropertyError\0", 25, 0, NULL, 0) = 25
sendto(, "\0", 1, 0, NULL, 0)= 1
sendto(, "Invalid property 'internal' of \0",
38, 0, NULL, 0) = 38
shutdown(, SHUT_WR) = 0
epoll_wait(3, [{EPOLLIN, {u32=, u64=}}], 18, 0) =
1
close() = 0
4. WTF, what would iterate over all the VMs? Maybe some script repeatedly
runs qvm-ls? Let's ps aux | grep qvm-ls that! During increased CPU
workload, I have identified:
qvm-ls --no-spinner --raw-data --fields NAME,FLAGS
5. During the current random CPU workload, I cannot reliably verify if it
is the cause of the increased CPU usage, but at least I can verify if it is
the cause of the error messages. So, I have tried the command while running
this:
(sudo strace -s 256 -p PID_OF_QUBESD 2>&1) | grep 'Invalid property'
And yes, it seems to be the cause of the error messages and maybe also the
source of increased CPU load.
6. Let's identify the script that runs the command: I ran htop, switched to
tree mode (key t), waited for the qvm-ls (using watch + ps aux + grep) and
typed “/qvm-ls”.
And the script to blame is – qubes-i3status
7. And yes, killing qubes-i3status has helped to decrease the CPU load.
After doing that, I was able to confirm that qvm-ls --no-spinner --raw-data
--fields NAME,FLAGS also causes the CPU load.
So, there are multiple causes combined:
* I have many VMs in my computer.
* I use i3 with qubes-i3status
* The script qubes-i3status calls command qvm-ls --no-spinner --raw-data
--fields NAME,FLAGS quite frequently.
* The command qvm-ls --no-spinner --raw-data --fields NAME,FLAGS seems to
cause high CPU load. Unfortunately, the process that shows the high CPU
usage is qubesd, not qvm-ls.
What can be improved:
a. Don't use qubes-i3status. Problem solved.
b. Optimize qvm-ls. Not sure how hard it is.
c. Optimize qubes-i3status. I am not sure about the ideal way of doing
that, but clearly running qvm-ls --no-spinner --raw-data --fields
NAME,FLAGS just to compute the number of running qubes is far from optimal.
One could add --running. And maybe it could have been written without
flags. The script just ignores VMs with the first flag being “0” (maybe in
order to ignore dom0) and the second flag being “r” (probably not needed
with --running).
Regards,
Vít Šesták 'v6ak'
On Monday, January 4, 2021 at 11:51:23 PM UTC+1 Vít Šesták wrote:
> Hello,
> I have dual-core i7 7500U with disabled hyperthreading. In dom0, I often
> have total CPU usage in tens of percents (often about 50 %, i.e., about
> fully utilized single core). When I look at htop in dom0, it is clearly
> caused by qubesd, which clearly uses the vast majority of CPU during these
> peaks. Note that these peaks look rather random, I see no relation to any
> activity. But they are quite frequent.
>
> When looking at the process tree, it has many child processes, probably
> one for each domU qube. But they utilize near zero CPU.
>
> The column TIME+ confirms my CPU% observation in long term.
>
> I am not sure where to find any relevant log. Maybe journalctl, but I have
> seen nothing suspicious there.
>
> Do you have any idea about the cause, solution or even a suggestion for
> debugging?
>
> Regards,
> Vít Šesták 'v6ak'
>
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