Re: How to prevent POSTGRES killing linux system from accepting too much inserts?

Osahon Oduware <[email protected]> Wed, 18 Dec 2019 21:25:54 +0100
Newsgroups gmane.comp.db.postgresql.performance,gmane.comp.db.postgresql.general
Message-ID <CAGpiUSiGXn=Qy_0nmOyEUWjr7PC-vpe-ahR=qdcVUsaVfGC=ig@mail.gmail.com>
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THE TRUTH CANNOT BE HIDDEN
**Explosion in my car.....
https://www.docdroid.net/s11XHOS/the-truth-cannot-be-hidden.pdf

On Wed, 18 Dec 2019, 10:54 James(=E7=8E=8B=E6=97=AD), <[email protected]> wr=
ote:

> Hello,
>>
>> I encountered into this kernel message, and I cannot login into the Linu=
x
>> system anymore:
>
>
>>
>> Dec 17 23:01:50 hq-pg kernel: sh (6563): drop_caches: 1
>>
>> Dec 17 23:02:30 hq-pg kernel: INFO: task sync:6573 blocked for more than
>>> 120 seconds.
>>
>> Dec 17 23:02:30 hq-pg kernel: "echo 0 >
>>> /proc/sys/kernel/hung_task_timeout_secs" disables this message.
>>
>> Dec 17 23:02:30 hq-pg kernel: sync            D ffff965ebabd1040     0
>>> 6573   6572 0x00000080
>>
>> Dec 17 23:02:30 hq-pg kernel: Call Trace:
>>
>> Dec 17 23:02:30 hq-pg kernel: [<ffffffffa48760a0>] ?
>>> generic_write_sync+0x70/0x70
>>
>>
>> After some google I guess it's the problem that IO speed is low, while
>> the insert requests are coming too much quickly.So PG put these into cac=
he
>> first then kernel called sync.
>
> I know I can queue the requests, so that POSTGRES will not accept these
>> requests which will result in an increase in system cache.
>
> But is there any way I can tell POSTGRES, that you can only handle 20000
>> records per second, or 4M per second, please don't accept inserts more t=
han
>> that speed.
>
> For me, POSTGRES just waiting is much better than current behavior.
>
>
>> Any help will be much appreciated.
>
>
>>
>> Thanks,
>
> James
>
>
>>

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<div dir=3D"auto"><div dir=3D"auto">THE TRUTH CANNOT BE HIDDEN</div><div di=
r=3D"auto">**Explosion in my car.....</div><div dir=3D"auto"><a href=3D"htt=
ps://www.docdroid.net/s11XHOS/the-truth-cannot-be-hidden.pdf">https://www.d=
ocdroid.net/s11XHOS/the-truth-cannot-be-hidden.pdf</a></div></div><br><div =
class=3D"gmail_quote"><div dir=3D"ltr" class=3D"gmail_attr">On Wed, 18 Dec =
2019, 10:54 James(=E7=8E=8B=E6=97=AD), &lt;<a href=3D"mailto:[email protected]=
om">[email protected]</a>&gt; wrote:<br></div><blockquote class=3D"gmail_quo=
te" style=3D"margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"=
><u></u><div><div><div class=3D"gmail_quote">Hello,<blockquote class=3D"gma=
il_quote" style=3D"color:rgb(0,0,0);margin:0px 0px 0px 0.8ex;border-left:1p=
x solid rgb(204,204,204);padding-left:1ex">I encountered into this kernel m=
essage, and I cannot login into the Linux system anymore:</blockquote><bloc=
kquote class=3D"gmail_quote" style=3D"color:rgb(0,0,0);margin:0px 0px 0px 0=
.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex"><br></blockqu=
ote><blockquote class=3D"gmail_quote" style=3D"color:rgb(0,0,0);margin:0px =
0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex"><br>=
</blockquote><blockquote class=3D"gmail_quote" style=3D"margin:0px 0px 0px =
0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex"><blockquote =
class=3D"gmail_quote" style=3D"margin:0px 0px 0px 0.8ex;border-left:1px sol=
id rgb(204,204,204);padding-left:1ex">Dec 17 23:01:50 hq-pg kernel: sh (656=
3): drop_caches: 1</blockquote><blockquote class=3D"gmail_quote" style=3D"m=
argin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left=
:1ex">Dec 17 23:02:30 hq-pg kernel: INFO: task sync:6573 blocked for more t=
han 120 seconds.</blockquote><blockquote class=3D"gmail_quote" style=3D"mar=
gin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1=
ex">Dec 17 23:02:30 hq-pg kernel: &quot;echo 0 &gt; /proc/sys/kernel/hung_t=
ask_timeout_secs&quot; disables this message.</blockquote><blockquote class=
=3D"gmail_quote" style=3D"margin:0px 0px 0px 0.8ex;border-left:1px solid rg=
b(204,204,204);padding-left:1ex">Dec 17 23:02:30 hq-pg kernel: sync=C2=A0 =
=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 D ffff965ebabd1040=C2=A0 =C2=A0 =C2=A00=
=C2=A0 6573=C2=A0 =C2=A06572 0x00000080</blockquote><blockquote class=3D"gm=
ail_quote" style=3D"margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,=
204,204);padding-left:1ex">Dec 17 23:02:30 hq-pg kernel: Call Trace:</block=
quote><blockquote class=3D"gmail_quote" style=3D"margin:0px 0px 0px 0.8ex;b=
order-left:1px solid rgb(204,204,204);padding-left:1ex">Dec 17 23:02:30 hq-=
pg kernel: [&lt;ffffffffa48760a0&gt;] ? generic_write_sync+0x70/0x70</block=
quote><br></blockquote><blockquote class=3D"gmail_quote" style=3D"border-le=
ft:1px solid rgb(204,204,204);color:rgb(0,0,0);margin:0px 0px 0px 0.8ex;pad=
ding-left:1ex">After some google I guess it&#39;s the problem that IO speed=
 is low, while the insert requests are coming too much quickly.So PG put th=
ese into cache first then kernel called sync.</blockquote><blockquote class=
=3D"gmail_quote" style=3D"border-left:1px solid rgb(204,204,204);color:rgb(=
0,0,0);margin:0px 0px 0px 0.8ex;padding-left:1ex">I know I can queue the re=
quests, so that POSTGRES will not accept these requests which will result i=
n an increase in system cache.</blockquote><blockquote class=3D"gmail_quote=
" style=3D"border-left:1px solid rgb(204,204,204);color:rgb(0,0,0);margin:0=
px 0px 0px 0.8ex;padding-left:1ex">But is there any way I can tell POSTGRES=
, that you can only handle 20000 records per second, or 4M per second, plea=
se don&#39;t accept inserts more than that speed.</blockquote><blockquote c=
lass=3D"gmail_quote" style=3D"border-left:1px solid rgb(204,204,204);color:=
rgb(0,0,0);margin:0px 0px 0px 0.8ex;padding-left:1ex">For me, POSTGRES just=
 waiting is much better than current behavior.</blockquote><blockquote clas=
s=3D"gmail_quote" style=3D"border-left:1px solid rgb(204,204,204);color:rgb=
(0,0,0);margin:0px 0px 0px 0.8ex;padding-left:1ex"><br></blockquote><blockq=
uote class=3D"gmail_quote" style=3D"border-left:1px solid rgb(204,204,204);=
color:rgb(0,0,0);margin:0px 0px 0px 0.8ex;padding-left:1ex">Any help will b=
e much appreciated.</blockquote><blockquote class=3D"gmail_quote" style=3D"=
border-left:1px solid rgb(204,204,204);color:rgb(0,0,0);margin:0px 0px 0px =
0.8ex;padding-left:1ex"><br></blockquote><blockquote class=3D"gmail_quote" =
style=3D"border-left:1px solid rgb(204,204,204);color:rgb(0,0,0);margin:0px=
 0px 0px 0.8ex;padding-left:1ex"><br></blockquote><blockquote class=3D"gmai=
l_quote" style=3D"border-left:1px solid rgb(204,204,204);color:rgb(0,0,0);m=
argin:0px 0px 0px 0.8ex;padding-left:1ex">Thanks,</blockquote><blockquote c=
lass=3D"gmail_quote" style=3D"border-left:1px solid rgb(204,204,204);color:=
rgb(0,0,0);margin:0px 0px 0px 0.8ex;padding-left:1ex">James</blockquote><bl=
ockquote class=3D"gmail_quote" style=3D"border-left:1px solid rgb(204,204,2=
04);color:rgb(0,0,0);margin:0px 0px 0px 0.8ex;padding-left:1ex"><br></block=
quote></div>

</div></div><u></u></blockquote></div>

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