Steam uses 7.2% CPU, in Windows it's 0.0%
For the record, I've often found that the task manager was inaccurate in showing actual CPU usage.
openSUSE 12.2 x86_64 KDE4:
In System Monitor it changes between 0 and 4 % depending on the load here. «top» gives me values between 1.7 and 2.2. It's just a estimate, but this is on my system of course.
On my system (opensuse 12.2 64bit), it seems to spend a significant amount of time in sys.
Dual core i7-2677M CPU @ 1.80GHz (using ondeman freq governor, but I verified behavior is the same with performance governor)
KDE 4 with desktop effects disabled.
Sandybridge onchip intel graphics (it's using the VMware gallium driver from Mesa, which seems wrong. I'll try to change that)
laptop:~ # ps -ef | grep steam
username 5201 1450 0 19:25 pts/0 00:00:00 /bin/bash /home/username/.local/share/Steam/steam.sh
username 5247 5201 21 19:25 pts/0 00:00:11 /home/username/.local/share/Steam/ubuntu12_32/steam
I just left it idling on the store screen
laptop:~ # pidstat -p 5247 -u 5 6
Linux 3.4.11-2.16-desktop (laptop.site) 12/27/12 x86_64 (4 CPU)
19:27:31 PID %usr %system %guest %CPU CPU Command
19:27:36 5247 4.00 2.80 0.00 6.80 3 MainThrd
19:27:41 5247 4.80 2.40 0.00 7.20 0 MainThrd
19:27:46 5247 4.40 2.60 0.00 7.00 1 MainThrd
19:27:51 5247 4.40 3.00 0.00 7.40 1 MainThrd
19:27:56 5247 4.20 2.80 0.00 7.00 0 MainThrd
19:28:01 5247 4.40 3.00 0.00 7.40 1 MainThrd
Average: 5247 4.37 2.77 0.00 7.13 - MainThrd
Steam seems to crash a lot when trying to ltrace, but I did get a bit and it seems to spend most of the sys time in _newselect (select), and once I saw a pretty long poll.
As far as raw number of library/sys calls, here's the breakdown from ~20 seconds of it running:
16 SYS_tgkill
28 SYS_futex
110 SYS_ipc
110 SYS_nanosleep
110 SYS_rt_sigtimedwait
330 pthread_mutex_trylock
330 pthread_mutex_unlock
344 SYS_time
452 SYS__newselect
1114 SYS_gettimeofday
4929 SYS_writev
8673 SYS_poll
9670 SYS_socketcall
heiss, could you paste some system information? I ran pidstat a couple of times here for comparison: https://gist.github.com/4394595. ltrace just didn't want to play along …
My windows 7 x64 shows up to 17% normal mode, avarage about 3-5% of CPU using according to sys internals process explorer. Agree with @MrSchism default process explorer is a little bit inaccurate
The question is what does Steam need to poll its sockets so often for, if it's just a desktop application. Even watching outpot of strace attached to it is kind of scary.
Sorry, I didn't know that Close button closes the issue
lol
For the record, I've often found that the task manager was inaccurate in showing actual CPU usage.
Looks like you are correct, according to Sysinternals process explorer steam window (showing game library) cpu usage in Windows is actually around 2.2...2.3%
Did you try Powertop?
Who?
Powertop - https://01.org/powertop/ it's likely to be available in your distro's packager already.
In powertop, steam is by far on top with around 350 events/s
Should be noticeably better in the next release, although it will probably still be more CPU-intensive on X11 relative to Windows
For me it's around 6% (Core i3, dual core with HT). Good job and thank you very much Valve.
I personally wouldn't consider this "solved" given that steam running cases quite many cpu wakeups which means that on my notebook the fans run noticeably more than without steam running. I don't think I should have to use the steam webchat to chat with steam contacs only because the steam client produces so much cpu wakeups.
Consider only how much energy is globally wasted by idle steam clients...
I suggest using perf (perf top) to find out where the cpu cycles are wasted:
And while I don't know anything about the internals of steam I don't feel something like find_busiest_group needs to actually run that often.
@ChristophHaag investigating this issue is a good thing. Steam is still using around 10% CPU time?!
Well, on a 3632qm:
steam itself uses ~4-6%
CSteamController is a thread that jumps between 2.6 and 3.3%
Just idly displaying my library.
It is not much, but it is much more than it should be.
Interestingly, I have Steam using only
0,34% steamui.so [.] 0x0000000000dbdc3e
Have a Bumblee notbook and Steam running on the Intel graphics card. Maybe the performance issue is related to a certain hardware configuration or Kernel version?
I have Linux kernel 3.9.3-1-ARCH
This is still an issue. Both top and htop report Steam to be using 3-5% CPU at all times, even when Steam is minimized. This is on Fedora 19 with an Intel 4670K CPU.
Here's the output of strace -p $STEAMPID -c running for 60 seconds.
% time seconds usecs/call calls errors syscall
------ ----------- ----------- --------- --------- ----------------
98.88 1.382027 92 14946 poll
0.36 0.005000 5000 1 restart_syscall
0.30 0.004216 0 16058 11400 recv
0.20 0.002767 0 7939 clock_gettime
0.10 0.001421 0 4566 writev
0.05 0.000761 1 1134 nanosleep
0.02 0.000335 0 1134 1134 semop
0.02 0.000316 0 1134 select
0.02 0.000282 0 1134 1134 waitpid
0.02 0.000275 0 3524 time
0.01 0.000182 0 1134 read
0.00 0.000061 1 75 send
0.00 0.000025 0 108 tgkill
------ ----------- ----------- --------- --------- ----------------
100.00 1.397668 52887 13668 total
Nothing extracted yet.
On average opened steam window (showing game library) uses much more CPU in linux than it does in Windows.
Xubuntu 12.10 64bit AMD apu (dual core) E450 1.65GHz
Windows 7 64bit
![steam exe 00 cpu]()