Re: LTSP slowness problem

Jim Kinney <[email protected]> Tue, 14 Apr 2015 08:15:34 -0400
Newsgroups gmane.linux.redhat.k12osn
Message-ID <CAEo=5PxPyheTwswWSObKv4tgKedpUvhiK_C=VXXp=KFTqy0JAg@mail.gmail.com>
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That python process is eating the system.
Need cpuinfo as well. How many cores? A single core can get bogged down
swapping memory out between user jobs and system jobs.

Note: Intel cpus use their hyperthreading mode. That's only useful for
processes that are shared memory. When the use is non-shared memory work,
hyperthreading can actually slow down the system. I turn it off by default
in the bios.
On Apr 14, 2015 7:32 AM, "Kenneth Lundstr=C3=B6m" <kenneth.lundstrom@nudata=
.fi>
wrote:

>  Hi,
>
>
> here is a small capture of top results:
>
> top - 14:29:39 up 11 days,  5:43,  6 users,  load average: 1,98, 2,16, 2,=
03
> Tasks: 402 total,   3 running, 397 sleeping,   1 stopped,   1 zombie
> %Cpu(s): 12,4 us,  3,8 sy,  0,0 ni, 81,7 id,  2,0 wa,  0,0 hi,  0,1 si,
> 0,0 st
> KiB Mem:  16593728 total,  9841308 used,  6752420 free,   291936 buffers
> KiB Swap: 16773116 total,        0 used, 16773116 free.  6716260 cached M=
em
>
>   PID USER      PR  NI    VIRT    RES    SHR S  %CPU %MEM     TIME+ COMMA=
ND
> 11101 xx1    20   0  110524  34928  21764 R 100,0  0,2  10231:46 python
> 18506 xx1    20   0 1000664 278496  45620 S  16,9  1,7  13:57.25 firefox
> 32129 xx2      20   0  784320 274336  44752 S   3,0  1,7  12:11.78
> thunderbird
> 32133 xx2      20   0 1058788 352892  46728 R   2,7  2,1  13:16.16 firefo=
x
> 31698 root      20   0   10144   3268   2508 S   1,7  0,0   0:00.11 sshd
>    23 root      20   0       0      0      0 S   0,7  0,0   8:25.98
> ksoftirqd/3
> 16121 root      20   0       0      0      0 S   0,7  0,0   0:05.42
> kworker/1:2
>    18 root      20   0       0      0      0 S   0,3  0,0  10:11.20
> ksoftirqd/2
>    38 root      20   0       0      0      0 S   0,3  0,0   9:52.39
> ksoftirqd/6
>    43 root      20   0       0      0      0 S   0,3  0,0   8:30.15
> ksoftirqd/7
>  1776 xx3  20   0  335288  41872  19920 S   0,3  0,3   0:50.63
> plugin-containe
> 16798 xx4     20   0  874020 292644  45340 S   0,3  1,8   1:27.02 firefox
> 19382 xx4     20   0  233152  26560  16572 S   0,3  0,2   0:07.70
> plugin-containe
> 30002 xx2      20   0  231240  27512  17564 S   0,3  0,2   0:01.89
> plugin-containe
>
> If I remember correctly it is running on two harddisk but in mirror mode.
>
>
>
> Kenneth
>
>
>
>  -----Original message-----
> *From:* Jim Kinney <[email protected]>
> *Sent:* Tuesday 14th April 2015 14:27
> *To:* Support list for open source software in schools. <[email protected]=
m
> >
> *Subject:* Re: [K12OSN] LTSP slowness problem
>
> Sounds like the server is just too weak for the load. RAM matters.
> Multiple hard drives can make a big difference.
> 1g network for only 7 clients is plenty unless its all youtube videos.
> On Apr 14, 2015 7:01 AM, "Kenneth Lundstr=C3=B6m" <kenneth.lundstrom@nuda=
ta.fi>
> wrote:
>
>>  Hello everyone,
>>
>>
>> I have a strange problem that I have been trying to solve for months.
>>
>>
>> A client have a setup of 6-7 LTSP terminals and one server. Because of
>> room structure we need to have 3 switches, all are 1 GB. Server has one =
1GB
>> network card. As I couldn't get LTSP working on CentOS 7 I switched to
>> Ubuntu.
>>
>>
>> Problem is the slowness of the clients. If 1-2 are working everything is
>> fine, but when we have like 5 working the same time we get slowness, lik=
e
>> when writing an email in Thunderbird it just stops showing the writing o=
n
>> the screen.
>>
>>
>> I swtich away from KDE to LightDM (I think was the name), still same.
>>
>>
>> One thing we think might be the problem is the filemanager. When somebod=
y
>> open filemanager and looks at the folder with like 100 files everything
>> stop. All files are on the same server as LTSP is running.
>>
>>
>> Any ideas where to look for the problem and solving it.
>>
>>
>>
>> Kenneth
>>
>>
>>
>> _______________________________________________
>> K12OSN mailing list
>> [email protected]
>> https://www.redhat.com/mailman/listinfo/k12osn
>> For more info see <http://www.k12os.org>
>>
>  _______________________________________________
>
> K12OSN mailing list
> [email protected]
> https://www.redhat.com/mailman/listinfo/k12osn
>
> For more info see <http://www.k12os.org>
>
>

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<p dir=3D"ltr">That python process is eating the system. <br>
Need cpuinfo as well. How many cores? A single core can get bogged down swa=
pping memory out between user jobs and system jobs.</p>
<p dir=3D"ltr">Note: Intel cpus use their hyperthreading mode. That&#39;s o=
nly useful for processes that are shared memory. When the use is non-shared=
 memory work, hyperthreading can actually slow down the system. I turn it o=
ff by default in the bios.</p>
<div class=3D"gmail_quote">On Apr 14, 2015 7:32 AM, &quot;Kenneth Lundstr=
=C3=B6m&quot; &lt;<a href=3D"mailto:[email protected]">kenneth.lu=
[email protected]</a>&gt; wrote:<br type=3D"attribution"><blockquote class=
=3D"gmail_quote" style=3D"margin:0 0 0 .8ex;border-left:1px #ccc solid;padd=
ing-left:1ex"><u></u>

 =20
 =20
 =20

<div>
<p style=3D"padding:0;margin:0"><span style=3D"font-family:tahoma;font-size=
:10pt">Hi,<br></span></p>
<p style=3D"padding:0;margin:0"><span style=3D"font-family:tahoma;font-size=
:10pt"><br></span></p>
<p style=3D"padding:0;margin:0"><span style=3D"font-family:tahoma;font-size=
:10pt">here is a small capture of top results:<br></span></p>
<p style=3D"padding:0;margin:0"><span style=3D"font-family:tahoma;font-size=
:10pt">top - 14:29:39 up 11 days,=C2=A0 5:43,=C2=A0 6 users,=C2=A0 load ave=
rage: 1,98, 2,16, 2,03<br>Tasks: 402 total,=C2=A0=C2=A0 3 running, 397 slee=
ping,=C2=A0=C2=A0 1 stopped,=C2=A0=C2=A0 1 zombie<br>%Cpu(s): 12,4 us,=C2=
=A0 3,8 sy,=C2=A0 0,0 ni, 81,7 id,=C2=A0 2,0 wa,=C2=A0 0,0 hi,=C2=A0 0,1 si=
,=C2=A0 0,0 st<br>KiB Mem:=C2=A0 16593728 total,=C2=A0 9841308 used,=C2=A0 =
6752420 free,=C2=A0=C2=A0 291936 buffers<br>KiB Swap: 16773116 total,=C2=A0=
=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 0 used, 16773116 free.=C2=A0 6716260 c=
ached Mem<br><br>=C2=A0 PID USER=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 PR=C2=A0 NI=
=C2=A0=C2=A0=C2=A0 VIRT=C2=A0=C2=A0=C2=A0 RES=C2=A0=C2=A0=C2=A0 SHR S=C2=A0=
 %CPU %MEM=C2=A0=C2=A0=C2=A0=C2=A0 TIME+ COMMAND<br>11101 xx1 =C2=A0=C2=A0 =
20=C2=A0=C2=A0 0=C2=A0 110524=C2=A0 34928=C2=A0 21764 R 100,0=C2=A0 0,2=C2=
=A0 10231:46 python<br>18506 xx1 =C2=A0=C2=A0 20=C2=A0=C2=A0 0 1000664 2784=
96=C2=A0 45620 S=C2=A0 16,9=C2=A0 1,7=C2=A0 13:57.25 firefox<br>32129 xx2 =
=C2=A0=C2=A0=C2=A0=C2=A0 20=C2=A0=C2=A0 0=C2=A0 784320 274336=C2=A0 44752 S=
=C2=A0=C2=A0 3,0=C2=A0 1,7=C2=A0 12:11.78 thunderbird<br>32133 xx2 =C2=A0=
=C2=A0=C2=A0=C2=A0 20=C2=A0=C2=A0 0 1058788 352892=C2=A0 46728 R=C2=A0=C2=
=A0 2,7=C2=A0 2,1=C2=A0 13:16.16 firefox<br>31698 root=C2=A0=C2=A0=C2=A0=C2=
=A0=C2=A0 20=C2=A0=C2=A0 0=C2=A0=C2=A0 10144=C2=A0=C2=A0 3268=C2=A0=C2=A0 2=
508 S=C2=A0=C2=A0 1,7=C2=A0 0,0=C2=A0=C2=A0 0:00.11 sshd<br>=C2=A0=C2=A0 23=
 root=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 20=C2=A0=C2=A0 0=C2=A0=C2=A0=C2=A0=C2=
=A0=C2=A0=C2=A0 0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 0=C2=A0=C2=A0=C2=A0=C2=A0=
=C2=A0 0 S=C2=A0=C2=A0 0,7=C2=A0 0,0=C2=A0=C2=A0 8:25.98 ksoftirqd/3<br>161=
21 root=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 20=C2=A0=C2=A0 0=C2=A0=C2=A0=C2=A0=C2=
=A0=C2=A0=C2=A0 0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 0=C2=A0=C2=A0=C2=A0=C2=A0=
=C2=A0 0 S=C2=A0=C2=A0 0,7=C2=A0 0,0=C2=A0=C2=A0 0:05.42 kworker/1:2<br>=C2=
=A0=C2=A0 18 root=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 20=C2=A0=C2=A0 0=C2=A0=C2=
=A0=C2=A0=C2=A0=C2=A0=C2=A0 0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 0=C2=A0=C2=A0=
=C2=A0=C2=A0=C2=A0 0 S=C2=A0=C2=A0 0,3=C2=A0 0,0=C2=A0 10:11.20 ksoftirqd/2=
<br>=C2=A0=C2=A0 38 root=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 20=C2=A0=C2=A0 0=C2=
=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 0=C2=A0=
=C2=A0=C2=A0=C2=A0=C2=A0 0 S=C2=A0=C2=A0 0,3=C2=A0 0,0=C2=A0=C2=A0 9:52.39 =
ksoftirqd/6<br>=C2=A0=C2=A0 43 root=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 20=C2=A0=
=C2=A0 0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 0=C2=A0=C2=A0=C2=A0=C2=A0=C2=
=A0 0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 0 S=C2=A0=C2=A0 0,3=C2=A0 0,0=C2=A0=C2=
=A0 8:30.15 ksoftirqd/7<br>=C2=A01776 xx3=C2=A0 20=C2=A0=C2=A0 0=C2=A0 3352=
88=C2=A0 41872=C2=A0 19920 S=C2=A0=C2=A0 0,3=C2=A0 0,3=C2=A0=C2=A0 0:50.63 =
plugin-containe<br>16798 xx4 =C2=A0=C2=A0=C2=A0 20=C2=A0=C2=A0 0=C2=A0 8740=
20 292644=C2=A0 45340 S=C2=A0=C2=A0 0,3=C2=A0 1,8=C2=A0=C2=A0 1:27.02 firef=
ox<br>19382 xx4 =C2=A0=C2=A0=C2=A0 20=C2=A0=C2=A0 0=C2=A0 233152=C2=A0 2656=
0=C2=A0 16572 S=C2=A0=C2=A0 0,3=C2=A0 0,2=C2=A0=C2=A0 0:07.70 plugin-contai=
ne<br>30002 xx2 =C2=A0=C2=A0=C2=A0=C2=A0 20=C2=A0=C2=A0 0=C2=A0 231240=C2=
=A0 27512=C2=A0 17564 S=C2=A0=C2=A0 0,3=C2=A0 0,2=C2=A0=C2=A0 0:01.89 plugi=
n-containe<br><br></span></p>
<p style=3D"padding:0;margin:0"><span style=3D"font-family:tahoma;font-size=
:10pt">If I remember correctly it is running on two harddisk but in mirror =
mode. <br></span></p>
<p style=3D"padding:0;margin:0"><span style=3D"font-family:tahoma;font-size=
:10pt"><br></span></p>
<p style=3D"padding:0;margin:0"><span style=3D"font-family:tahoma;font-size=
:10pt"><br></span></p>
<p style=3D"padding:0;margin:0"><span style=3D"font-family:tahoma;font-size=
:10pt">Kenneth<br></span></p>
<p style=3D"padding:0;margin:0"><span style=3D"font-family:tahoma;font-size=
:10pt"><br></span></p>
<p style=3D"padding:0;margin:0"><span style=3D"font-family:tahoma;font-size=
:10pt"><br></span></p>
<div>
<blockquote style=3D"border-left:2px solid #325fba;padding-left:5px;margin:=
0px 5px"><span style=3D"font-family:tahoma,arial,helvetica,sans-serif;font-=
size:10pt">-----Original message-----<br><span><strong>From:</strong> Jim K=
inney=C2=A0&lt;<a href=3D"mailto:[email protected]" target=3D"_blank">ji=
[email protected]</a>&gt;</span><br><span><strong>Sent:</strong> Tuesday 1=
4th April 2015 14:27</span><br><span><strong>To:</strong> Support list for =
open source software in schools. &lt;<a href=3D"mailto:[email protected]" t=
arget=3D"_blank">[email protected]</a>&gt;</span><br><span><strong>Subject:=
</strong> Re: [K12OSN] LTSP slowness problem</span><br><br></span>
<p dir=3D"ltr">Sounds like the server is just too weak for the load. RAM ma=
tters. Multiple hard drives can make a big difference.<br> 1g network for o=
nly 7 clients is plenty unless its all youtube videos.</p>
<div class=3D"gmail_quote">On Apr 14, 2015 7:01 AM, &quot;Kenneth Lundstr=
=C3=B6m&quot; &lt;<a href=3D"mailto:[email protected]" title=3D"T=
his external link will open in a new window" target=3D"_blank">kenneth.lund=
[email protected]</a>&gt; wrote:<br>
<blockquote class=3D"gmail_quote" style=3D"margin:0 0 0 .8ex;border-left:1p=
x #ccc solid;padding-left:1ex">
<div>
<p style=3D"padding:0;margin:0"><span style=3D"font-family:tahoma;font-size=
:10pt">Hello everyone,<br></span></p>
<p style=3D"padding:0;margin:0"><span style=3D"font-family:tahoma;font-size=
:10pt"><br></span></p>
<p style=3D"padding:0;margin:0"><span style=3D"font-family:tahoma;font-size=
:10pt">I have a strange problem that I have been trying to solve for months=
. <br></span></p>
<p style=3D"padding:0;margin:0"><span style=3D"font-family:tahoma;font-size=
:10pt"><br></span></p>
<p style=3D"padding:0;margin:0"><span style=3D"font-family:tahoma;font-size=
:10pt">A client have a setup of 6-7 LTSP terminals and one server. Because =
of room structure we need to have 3 switches, all are 1 GB. Server has one =
1GB network card. As I couldn&#39;t get LTSP working on CentOS 7 I switched=
 to Ubuntu. <br></span></p>
<p style=3D"padding:0;margin:0"><span style=3D"font-family:tahoma;font-size=
:10pt"><br></span></p>
<p style=3D"padding:0;margin:0"><span style=3D"font-family:tahoma;font-size=
:10pt">Problem is the slowness of the clients. If 1-2 are working everythin=
g is fine, but when we have like 5 working the same time we get slowness, l=
ike when writing an email in Thunderbird it just stops showing the writing =
on the screen. <br></span></p>
<p style=3D"padding:0;margin:0"><span style=3D"font-family:tahoma;font-size=
:10pt"><br></span></p>
<p style=3D"padding:0;margin:0"><span style=3D"font-family:tahoma;font-size=
:10pt">I swtich away from KDE to LightDM (I think was the name), still same=
. <br></span></p>
<p style=3D"padding:0;margin:0"><span style=3D"font-family:tahoma;font-size=
:10pt"><br></span></p>
<p style=3D"padding:0;margin:0"><span style=3D"font-family:tahoma;font-size=
:10pt">One thing we think might be the problem is the filemanager. When som=
ebody open filemanager and looks at the folder with like 100 files everythi=
ng stop. All files are on the same server as LTSP is running. <br></span></=
p>
<p style=3D"padding:0;margin:0"><span style=3D"font-family:tahoma;font-size=
:10pt"><br></span></p>
<p style=3D"padding:0;margin:0"><span style=3D"font-family:tahoma;font-size=
:10pt">Any ideas where to look for the problem and solving it. <br></span><=
/p>
<p style=3D"padding:0;margin:0"><span style=3D"font-family:tahoma;font-size=
:10pt"><br></span></p>
<p style=3D"padding:0;margin:0"><span style=3D"font-family:tahoma;font-size=
:10pt"><br></span></p>
<p style=3D"padding:0;margin:0"><span style=3D"font-family:tahoma;font-size=
:10pt">Kenneth<br></span></p>
<p style=3D"padding:0;margin:0"><span style=3D"font-family:tahoma;font-size=
:10pt"><br></span></p>
</div>
<br>_______________________________________________<br> K12OSN mailing list=
<br> <a href=3D"mailto:[email protected]" title=3D"This external link will =
open in a new window" target=3D"_blank">[email protected]</a><br> <a href=
=3D"https://www.redhat.com/mailman/listinfo/k12osn" title=3D"This external =
link will open in a new window" target=3D"_blank">https://www.redhat.com/ma=
ilman/listinfo/k12osn</a><br> For more info see &lt;<a href=3D"http://www.k=
12os.org" title=3D"This external link will open in a new window" target=3D"=
_blank">http://www.k12os.org</a>&gt;<br></blockquote>
</div>
<pre>_______________________________________________<br>
K12OSN mailing list<br>
<a href=3D"mailto:[email protected]" target=3D"_blank">[email protected]</a=
><br>
<a href=3D"https://www.redhat.com/mailman/listinfo/k12osn" target=3D"_blank=
">https://www.redhat.com/mailman/listinfo/k12osn</a><br>
For more info see &lt;<a href=3D"http://www.k12os.org" target=3D"_blank">ht=
tp://www.k12os.org</a>&gt;</pre>
</blockquote>
</div>
</div>
</blockquote></div>

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_______________________________________________
K12OSN mailing list
[email protected]
https://www.redhat.com/mailman/listinfo/k12osn
For more info see <http://www.k12os.org>
--===============4048988257861124898==--