Skip site navigation (1)Skip section navigation (2)
Date:      Mon, 3 Jan 2000 17:25:27 -0600 
From:      Jason Young <doogie@staff.accessus.net>
To:        'Matthew Dillon' <dillon@apollo.backplane.com>, George Cox <gjvc@extremis.demon.co.uk>
Cc:        freebsd-hackers@FreeBSD.ORG
Subject:   RE: Repeated softupdates panics in 3.3-STABLE
Message-ID:  <ABD44D466F85D311A69900A0C900DB6BC5BA@staff.accessus.net>

next in thread | raw e-mail | index | archive | help
This message is in MIME format. Since your mail reader does not understand
this format, some or all of this message may not be legible.

------_=_NextPart_001_01BF5641.D387C89C
Content-Type: text/plain;
	charset="iso-8859-1"


A "pending ops" panic can be induced in fairly short order by running the
SMTP performance tests that come with Postfix. Specifically, run
smtpstone/smtp-source running many parallel deliveries into a Postfix mail
daemon setup running on the same machine. I had always assumed that this
meant softupdates was getting too behind (the test delivers hundreds of
mails per second with decent disk setups). I wasn't able to mentally parse
the code well enough to confirm that.

This is in all 3.x revisions that I've tested, since from back around the
time of 3.0-CURRENT's great ELF transition, to 3.3-RELEASE. If somebody's
interested, I can create this setup and try to duplicate the problem again.

> -----Original Message-----
> From: Matthew Dillon [mailto:dillon@apollo.backplane.com]
> Sent: Monday, January 03, 2000 4:21 PM
> To: George Cox
> Cc: freebsd-hackers@FreeBSD.ORG
> Subject: Re: Repeated softupdates panics in 3.3-STABLE
> 
> 
> :On 03/01 16:29, Keith Stevenson wrote:
> :
> :> It looks like I may have spoken too soon when I mentioned 
> that I had no
> :> problems with softupdates on my postfix based mail server. 
>  I have now had
> :> two panics in the last month with a panicstr of 
> "softdep_lock: locking
> :> against myself".  I thought that the first one might have 
> been a fluke until
> :> it repeated itself today.
> :
> :I too have seen this "softdep_lock: locking against myself" 
> panic on a Postfix
> :server.  I was able to trigger it I think maybe twice by 
> issuing a 'postfix
> :flush' command. :-/  This _was_ some months ago, when there 
> was the odd commit
> :to the softupdates code going in, which suggests it's kind 
> of a long standing
> :bug. :-( 
> 
>     Well, in Keith's case the locking-against-myself panic is not the
>     cause, but the effect of the 'softdep_fsync: pending ops' panic
>     that occured just before it.
> 
>     I've never seeing a pending ops panic before, this is going to be
>     one for Kirk to track down.  Be sure to keep your core dump and
>     your debug kernel.  In fact, if you could gzip them both 
> up and make
>     them available to me and Kirk via a hidden ftp or hidden URL I
>     would appreciate it.  NOTE!  Kernel core dumps often contain 
>     sensitive information such as pieces of the password file, do not
>     make your core available to the general lists!
> 
> 					-Matt
> 					Matthew Dillon 
> 					<dillon@backplane.com>
> 
> 
> To Unsubscribe: send mail to majordomo@FreeBSD.org
> with "unsubscribe freebsd-hackers" in the body of the message
> 

------_=_NextPart_001_01BF5641.D387C89C
Content-Type: text/html;
	charset="iso-8859-1"
Content-Transfer-Encoding: quoted-printable

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 3.2//EN">
<HTML>
<HEAD>
<META HTTP-EQUIV=3D"Content-Type" CONTENT=3D"text/html; =
charset=3Diso-8859-1">
<META NAME=3D"Generator" CONTENT=3D"MS Exchange Server version =
5.5.2650.12">
<TITLE>RE: Repeated softupdates panics in 3.3-STABLE</TITLE>
</HEAD>
<BODY>
<BR>

<P><FONT SIZE=3D2>A &quot;pending ops&quot; panic can be induced in =
fairly short order by running the SMTP performance tests that come with =
Postfix. Specifically, run smtpstone/smtp-source running many parallel =
deliveries into a Postfix mail daemon setup running on the same =
machine. I had always assumed that this meant softupdates was getting =
too behind (the test delivers hundreds of mails per second with decent =
disk setups). I wasn't able to mentally parse the code well enough to =
confirm that.</FONT></P>

<P><FONT SIZE=3D2>This is in all 3.x revisions that I've tested, since =
from back around the time of 3.0-CURRENT's great ELF transition, to =
3.3-RELEASE. If somebody's interested, I can create this setup and try =
to duplicate the problem again.</FONT></P>

<P><FONT SIZE=3D2>&gt; -----Original Message-----</FONT>
<BR><FONT SIZE=3D2>&gt; From: Matthew Dillon [<A =
HREF=3D"mailto:dillon@apollo.backplane.com">mailto:dillon@apollo.backpla=
ne.com</A>]</FONT>
<BR><FONT SIZE=3D2>&gt; Sent: Monday, January 03, 2000 4:21 PM</FONT>
<BR><FONT SIZE=3D2>&gt; To: George Cox</FONT>
<BR><FONT SIZE=3D2>&gt; Cc: freebsd-hackers@FreeBSD.ORG</FONT>
<BR><FONT SIZE=3D2>&gt; Subject: Re: Repeated softupdates panics in =
3.3-STABLE</FONT>
<BR><FONT SIZE=3D2>&gt; </FONT>
<BR><FONT SIZE=3D2>&gt; </FONT>
<BR><FONT SIZE=3D2>&gt; :On 03/01 16:29, Keith Stevenson wrote:</FONT>
<BR><FONT SIZE=3D2>&gt; :</FONT>
<BR><FONT SIZE=3D2>&gt; :&gt; It looks like I may have spoken too soon =
when I mentioned </FONT>
<BR><FONT SIZE=3D2>&gt; that I had no</FONT>
<BR><FONT SIZE=3D2>&gt; :&gt; problems with softupdates on my postfix =
based mail server. </FONT>
<BR><FONT SIZE=3D2>&gt;&nbsp; I have now had</FONT>
<BR><FONT SIZE=3D2>&gt; :&gt; two panics in the last month with a =
panicstr of </FONT>
<BR><FONT SIZE=3D2>&gt; &quot;softdep_lock: locking</FONT>
<BR><FONT SIZE=3D2>&gt; :&gt; against myself&quot;.&nbsp; I thought =
that the first one might have </FONT>
<BR><FONT SIZE=3D2>&gt; been a fluke until</FONT>
<BR><FONT SIZE=3D2>&gt; :&gt; it repeated itself today.</FONT>
<BR><FONT SIZE=3D2>&gt; :</FONT>
<BR><FONT SIZE=3D2>&gt; :I too have seen this &quot;softdep_lock: =
locking against myself&quot; </FONT>
<BR><FONT SIZE=3D2>&gt; panic on a Postfix</FONT>
<BR><FONT SIZE=3D2>&gt; :server.&nbsp; I was able to trigger it I think =
maybe twice by </FONT>
<BR><FONT SIZE=3D2>&gt; issuing a 'postfix</FONT>
<BR><FONT SIZE=3D2>&gt; :flush' command. :-/&nbsp; This _was_ some =
months ago, when there </FONT>
<BR><FONT SIZE=3D2>&gt; was the odd commit</FONT>
<BR><FONT SIZE=3D2>&gt; :to the softupdates code going in, which =
suggests it's kind </FONT>
<BR><FONT SIZE=3D2>&gt; of a long standing</FONT>
<BR><FONT SIZE=3D2>&gt; :bug. :-( </FONT>
<BR><FONT SIZE=3D2>&gt; </FONT>
<BR><FONT SIZE=3D2>&gt;&nbsp;&nbsp;&nbsp;&nbsp; Well, in Keith's case =
the locking-against-myself panic is not the</FONT>
<BR><FONT SIZE=3D2>&gt;&nbsp;&nbsp;&nbsp;&nbsp; cause, but the effect =
of the 'softdep_fsync: pending ops' panic</FONT>
<BR><FONT SIZE=3D2>&gt;&nbsp;&nbsp;&nbsp;&nbsp; that occured just =
before it.</FONT>
<BR><FONT SIZE=3D2>&gt; </FONT>
<BR><FONT SIZE=3D2>&gt;&nbsp;&nbsp;&nbsp;&nbsp; I've never seeing a =
pending ops panic before, this is going to be</FONT>
<BR><FONT SIZE=3D2>&gt;&nbsp;&nbsp;&nbsp;&nbsp; one for Kirk to track =
down.&nbsp; Be sure to keep your core dump and</FONT>
<BR><FONT SIZE=3D2>&gt;&nbsp;&nbsp;&nbsp;&nbsp; your debug =
kernel.&nbsp; In fact, if you could gzip them both </FONT>
<BR><FONT SIZE=3D2>&gt; up and make</FONT>
<BR><FONT SIZE=3D2>&gt;&nbsp;&nbsp;&nbsp;&nbsp; them available to me =
and Kirk via a hidden ftp or hidden URL I</FONT>
<BR><FONT SIZE=3D2>&gt;&nbsp;&nbsp;&nbsp;&nbsp; would appreciate =
it.&nbsp; NOTE!&nbsp; Kernel core dumps often contain </FONT>
<BR><FONT SIZE=3D2>&gt;&nbsp;&nbsp;&nbsp;&nbsp; sensitive information =
such as pieces of the password file, do not</FONT>
<BR><FONT SIZE=3D2>&gt;&nbsp;&nbsp;&nbsp;&nbsp; make your core =
available to the general lists!</FONT>
<BR><FONT SIZE=3D2>&gt; </FONT>
<BR><FONT SIZE=3D2>&gt; &nbsp;&nbsp;&nbsp;&nbsp;&nbsp; =
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; =
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; =
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; =
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; -Matt</FONT>
<BR><FONT SIZE=3D2>&gt; &nbsp;&nbsp;&nbsp;&nbsp;&nbsp; =
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; =
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; =
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; =
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; Matthew Dillon </FONT>
<BR><FONT SIZE=3D2>&gt; &nbsp;&nbsp;&nbsp;&nbsp;&nbsp; =
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; =
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; =
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; =
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; =
&lt;dillon@backplane.com&gt;</FONT>
<BR><FONT SIZE=3D2>&gt; </FONT>
<BR><FONT SIZE=3D2>&gt; </FONT>
<BR><FONT SIZE=3D2>&gt; To Unsubscribe: send mail to =
majordomo@FreeBSD.org</FONT>
<BR><FONT SIZE=3D2>&gt; with &quot;unsubscribe freebsd-hackers&quot; in =
the body of the message</FONT>
<BR><FONT SIZE=3D2>&gt; </FONT>
</P>

</BODY>
</HTML>
------_=_NextPart_001_01BF5641.D387C89C--


To Unsubscribe: send mail to majordomo@FreeBSD.org
with "unsubscribe freebsd-hackers" in the body of the message




Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?ABD44D466F85D311A69900A0C900DB6BC5BA>