Matt Ayres
2006-Jan-31 20:30 UTC
[Xen-devel] Re: [Xen-changelog] Fix VCPU locking in sched_adjdom for multi-VCPU guests
Does this commit in way way affect bug id # 502? _______________________________________________ Xen-devel mailing list Xen-devel@lists.xensource.com http://lists.xensource.com/xen-devel
Keir Fraser
2006-Jan-31 22:35 UTC
Re: [Xen-devel] Re: [Xen-changelog] Fix VCPU locking in sched_adjdom for multi-VCPU guests
No chance. But noone will be able to tell what BUG you are talking about, since you provide many attachments but no output from the BUGing kernel. -- Keir On 31 Jan 2006, at 20:30, Matt Ayres wrote:> Does this commit in way way affect bug id # 502? > > _______________________________________________ > Xen-devel mailing list > Xen-devel@lists.xensource.com > http://lists.xensource.com/xen-devel_______________________________________________ Xen-devel mailing list Xen-devel@lists.xensource.com http://lists.xensource.com/xen-devel
Matt Ayres
2006-Jan-31 22:42 UTC
Re: [Xen-devel] Re: [Xen-changelog] Fix VCPU locking in sched_adjdom for multi-VCPU guests
<puts on dunce hat> I''ve created a comment with the BUG. I remember I was going to have xen-bugtool include /var/log/messages, but later decided I didn''t want so many system details put out in public. Thank you, Matt Ayres Keir Fraser wrote:> > No chance. But noone will be able to tell what BUG you are talking > about, since you provide many attachments but no output from the BUGing > kernel. > > -- Keir > > On 31 Jan 2006, at 20:30, Matt Ayres wrote: > >> Does this commit in way way affect bug id # 502? >> >> _______________________________________________ >> Xen-devel mailing list >> Xen-devel@lists.xensource.com >> http://lists.xensource.com/xen-devel >_______________________________________________ Xen-devel mailing list Xen-devel@lists.xensource.com http://lists.xensource.com/xen-devel
Keir Fraser
2006-Jan-31 23:57 UTC
Re: [Xen-devel] Re: [Xen-changelog] Fix VCPU locking in sched_adjdom for multi-VCPU guests
On 31 Jan 2006, at 22:42, Matt Ayres wrote:> <puts on dunce hat> > > I''ve created a comment with the BUG. I remember I was going to have > xen-bugtool include /var/log/messages, but later decided I didn''t want > so many system details put out in public.How tight on memory are you running the system? The BUG is probably happening because the guest is failing to allocate a page of memory below 4GB. Since Xen tries to give out memory below 4GB last, that probably means there is very little available memory. Obviously we need a better fallback strategy than BUG(). :-) -- Keir _______________________________________________ Xen-devel mailing list Xen-devel@lists.xensource.com http://lists.xensource.com/xen-devel
Matt Ayres
2006-Feb-01 16:08 UTC
Re: Linux 2.6 guest BUG(). (was: Re: [Xen-devel] Re: [Xen-changelog] Fix VCPU locking in sched_adjdom for multi-VCPU guests)
Keir Fraser wrote:> > On 31 Jan 2006, at 22:42, Matt Ayres wrote: > >> <puts on dunce hat> >> >> I''ve created a comment with the BUG. I remember I was going to have >> xen-bugtool include /var/log/messages, but later decided I didn''t want >> so many system details put out in public. > > How tight on memory are you running the system? The BUG is probably > happening because the guest is failing to allocate a page of memory > below 4GB. Since Xen tries to give out memory below 4GB last, that > probably means there is very little available memory. >I can provide dozens of BUG()''s if required. It just happened again on a host in dom0 to the sshd daemon and now that port is locked (netstat -nlp reports "-" as the process name). I am able to access the server via the console. I assume you mean Xen''s memory usage. I am showing 141MB free out of 8112MB total. Our scripts to add accounts don''t allow adding more accounts then there is memory for, we actually leave about 128MB as a buffer.> Obviously we need a better fallback strategy than BUG(). :-) >Alright captain, what do I need to do on my end? Grepping /var/log/messages for "syscall" grants about 20+ results so something is going very wrong. Thank you, Matt Ayres _______________________________________________ Xen-devel mailing list Xen-devel@lists.xensource.com http://lists.xensource.com/xen-devel
Keir Fraser
2006-Feb-01 16:27 UTC
Re: Linux 2.6 guest BUG(). (was: Re: [Xen-devel] Re: [Xen-changelog] Fix VCPU locking in sched_adjdom for multi-VCPU guests)
On 1 Feb 2006, at 16:08, Matt Ayres wrote:> I can provide dozens of BUG()''s if required. It just happened again > on a host in dom0 to the sshd daemon and now that port is locked > (netstat -nlp reports "-" as the process name). I am able to access > the server via the console. > > I assume you mean Xen''s memory usage. I am showing 141MB free out of > 8112MB total. Our scripts to add accounts don''t allow adding more > accounts then there is memory for, we actually leave about 128MB as a > buffer.That''s a bit odd then. If you don''t explicitly specify dom0''s memory allocation at boot time then you should end up with 128MB ''slack'' left unallocated. And that should all be <4GB. If you are giving dom0 all of memory on boot, and then reducing it later, that could be a problem (dom0 may end up giving back only memory >4GB). -- Keir _______________________________________________ Xen-devel mailing list Xen-devel@lists.xensource.com http://lists.xensource.com/xen-devel
Keir Fraser wrote:> > On 1 Feb 2006, at 16:08, Matt Ayres wrote: > >> >> I assume you mean Xen''s memory usage. I am showing 141MB free out of >> 8112MB total. Our scripts to add accounts don''t allow adding more >> accounts then there is memory for, we actually leave about 128MB as a >> buffer. > > That''s a bit odd then. If you don''t explicitly specify dom0''s memory > allocation at boot time then you should end up with 128MB ''slack'' left > unallocated. And that should all be <4GB. > > If you are giving dom0 all of memory on boot, and then reducing it > later, that could be a problem (dom0 may end up giving back only memory > >4GB).I am allocating 256MB of RAM to dom0. I am running Fedora Core 4. On this particular server I am running httpd/mysqld on the host with a fair amount of activity to it, but I have extended swap space to 1GB and tuned both apps for low memory usage. The memory is set statically via kernel line in grub. (dom0-min-mem 262144) is set in xend-config.sxp to ensure it keeps the memory allocated to it. Thank you, Matt Ayres _______________________________________________ Xen-devel mailing list Xen-devel@lists.xensource.com http://lists.xensource.com/xen-devel
Keir Fraser wrote:> > On 1 Feb 2006, at 16:08, Matt Ayres wrote: > >> I can provide dozens of BUG()''s if required. It just happened again >> on a host in dom0 to the sshd daemon and now that port is locked >> (netstat -nlp reports "-" as the process name). I am able to access >> the server via the console. >> >> I assume you mean Xen''s memory usage. I am showing 141MB free out of >> 8112MB total. Our scripts to add accounts don''t allow adding more >> accounts then there is memory for, we actually leave about 128MB as a >> buffer. > > That''s a bit odd then. If you don''t explicitly specify dom0''s memory > allocation at boot time then you should end up with 128MB ''slack'' left > unallocated. And that should all be <4GB. > > If you are giving dom0 all of memory on boot, and then reducing it > later, that could be a problem (dom0 may end up giving back only memory > >4GB). >Just as an update, I just "upgraded" this specific host from -unstable to 3.0-testing (3.0.1) and I will report back if I still receive these BUG()''s. _______________________________________________ Xen-devel mailing list Xen-devel@lists.xensource.com http://lists.xensource.com/xen-devel