Mark Williamson
2005-Mar-10 18:39 UTC
Re: [Xen-devel] out-of-memory problem when restoring ballooned domains
Can you show us the output of xm list after the restore failure? It''d be interesting to see how much memory Xen thinks the domains are occupying. Cheers, Mark On Thursday 10 March 2005 18:42, Lars Rasmusson wrote:> Hi, > > I have a problem with the balloon functionality. > > I have a 2G memory machine (with 2 CPUs). > > I want to create three (or more) user domains, > each configured to have 2G (or 1800MB) of RAM, > but ballooned down to 128 MB. > > The reason is that I want to be able to change the > size of the balloons during run time, and I want > each of the domains to be able to potentially get > all (or almost all) of the memory. > > I first create the domains t1, t2, and t3: > > xm create t1 memory=1800 > xm balloon t1 128 > # wait until the balloon is inflated > xm save t1 t1.saved > > and repeat for t2 and t3. Notice that I can > create the domains with maximum memory since > the other domains are not using any RAM at > the time. > > Here comes my problem: > > When I do > > xm restore t1.saved > xm restore t2.saved > xm restore t3.saved > > I get "Error: 1" when I create the third > domain. I get the feeling it has something to > do with "not enough memory" (is that correct?) > > So even though the three 128 Mb domains should > fit easily within the approx 2G RAM, Xen doesn''t > think so. Which is why I''ve come to think there > might be some problem with how it is counting available RAM. > > - Is Xen taking ballooned memory into account properly? > > - Is it interpreting the info in the .saved file correctly? > > If that is the bug, I then wonder why I''m able to get two > user domains up and running, and not just one... > Could that be related to that the machine is a 2 CPU machine? > > Well that''s just speculation... Does anyone have any > suggestions what I might be doing wrong, or where the > problem may be? > > Cheers, > Lars Rasmusson > > > > > > > ------------------------------------------------------- > SF email is sponsored by - The IT Product Guide > Read honest & candid reviews on hundreds of IT Products from real users. > Discover which products truly live up to the hype. Start reading now. > http://ads.osdn.com/?ad_id=6595&alloc_id=14396&op=click > _______________________________________________ > Xen-devel mailing list > Xen-devel@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/xen-devel------------------------------------------------------- SF email is sponsored by - The IT Product Guide Read honest & candid reviews on hundreds of IT Products from real users. Discover which products truly live up to the hype. Start reading now. http://ads.osdn.com/?ad_id=6595&alloc_id=14396&op=click _______________________________________________ Xen-devel mailing list Xen-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/xen-devel
Lars Rasmusson
2005-Mar-10 18:42 UTC
[Xen-devel] out-of-memory problem when restoring ballooned domains
Hi, I have a problem with the balloon functionality. I have a 2G memory machine (with 2 CPUs). I want to create three (or more) user domains, each configured to have 2G (or 1800MB) of RAM, but ballooned down to 128 MB. The reason is that I want to be able to change the size of the balloons during run time, and I want each of the domains to be able to potentially get all (or almost all) of the memory. I first create the domains t1, t2, and t3: xm create t1 memory=1800 xm balloon t1 128 # wait until the balloon is inflated xm save t1 t1.saved and repeat for t2 and t3. Notice that I can create the domains with maximum memory since the other domains are not using any RAM at the time. Here comes my problem: When I do xm restore t1.saved xm restore t2.saved xm restore t3.saved I get "Error: 1" when I create the third domain. I get the feeling it has something to do with "not enough memory" (is that correct?) So even though the three 128 Mb domains should fit easily within the approx 2G RAM, Xen doesn''t think so. Which is why I''ve come to think there might be some problem with how it is counting available RAM. - Is Xen taking ballooned memory into account properly? - Is it interpreting the info in the .saved file correctly? If that is the bug, I then wonder why I''m able to get two user domains up and running, and not just one... Could that be related to that the machine is a 2 CPU machine? Well that''s just speculation... Does anyone have any suggestions what I might be doing wrong, or where the problem may be? Cheers, Lars Rasmusson ------------------------------------------------------- SF email is sponsored by - The IT Product Guide Read honest & candid reviews on hundreds of IT Products from real users. Discover which products truly live up to the hype. Start reading now. http://ads.osdn.com/?ad_id=6595&alloc_id=14396&op=click _______________________________________________ Xen-devel mailing list Xen-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/xen-devel
Lars Rasmusson
2005-Mar-10 18:54 UTC
Re: [Xen-devel] out-of-memory problem when restoring ballooned domains
It seems to compute it just right... # xm list Name Id Mem(MB) CPU State Time(s) Console Domain-0 0 123 0 r---- 330.2 t1 19 128 0 -b--- 0.0 9619 t2 20 128 1 -b--- 0.0 9620 # xm info system : Linux host : hpl1-024-01-eth0.hpl.hp.com release : 2.6.10-xen0 version : #1 Thu Mar 10 09:42:16 PST 2005 machine : i686 cores : 2 hyperthreads_per_core : 1 cpu_mhz : 1000 memory : 2047 free_memory : 1639 # xm restore t3.saved Error: 1 # xm save t1 t1.saved # xm save t2 t2.saved # xm restore t3.saved # xm list Name Id Mem(MB) CPU State Time(s) Console Domain-0 0 123 0 r---- 347.4 t3 22 128 0 -b--- 0.0 9622 So all domains have 128 Mb, and xen seems to count the memory fine... (FYI I''m using xen-2.0-testing, checked out from bitkeeper this morning) On Thu, 2005-03-10 at 18:39 +0000, Mark Williamson wrote:> Can you show us the output of xm list after the restore failure? It''d be > interesting to see how much memory Xen thinks the domains are occupying. > > Cheers, > Mark > > On Thursday 10 March 2005 18:42, Lars Rasmusson wrote: > > Hi, > > > > I have a problem with the balloon functionality. > > > > I have a 2G memory machine (with 2 CPUs). > > > > I want to create three (or more) user domains, > > each configured to have 2G (or 1800MB) of RAM, > > but ballooned down to 128 MB. > > > > The reason is that I want to be able to change the > > size of the balloons during run time, and I want > > each of the domains to be able to potentially get > > all (or almost all) of the memory. > > > > I first create the domains t1, t2, and t3: > > > > xm create t1 memory=1800 > > xm balloon t1 128 > > # wait until the balloon is inflated > > xm save t1 t1.saved > > > > and repeat for t2 and t3. Notice that I can > > create the domains with maximum memory since > > the other domains are not using any RAM at > > the time. > > > > Here comes my problem: > > > > When I do > > > > xm restore t1.saved > > xm restore t2.saved > > xm restore t3.saved > > > > I get "Error: 1" when I create the third > > domain. I get the feeling it has something to > > do with "not enough memory" (is that correct?) > > > > So even though the three 128 Mb domains should > > fit easily within the approx 2G RAM, Xen doesn''t > > think so. Which is why I''ve come to think there > > might be some problem with how it is counting available RAM. > > > > - Is Xen taking ballooned memory into account properly? > > > > - Is it interpreting the info in the .saved file correctly? > > > > If that is the bug, I then wonder why I''m able to get two > > user domains up and running, and not just one... > > Could that be related to that the machine is a 2 CPU machine? > > > > Well that''s just speculation... Does anyone have any > > suggestions what I might be doing wrong, or where the > > problem may be? > > > > Cheers, > > Lars Rasmusson > > > > > > > > > > > > > > ------------------------------------------------------- > > SF email is sponsored by - The IT Product Guide > > Read honest & candid reviews on hundreds of IT Products from real users. > > Discover which products truly live up to the hype. Start reading now. > > http://ads.osdn.com/?ad_id=6595&alloc_id=14396&op=click > > _______________________________________________ > > Xen-devel mailing list > > Xen-devel@lists.sourceforge.net > > https://lists.sourceforge.net/lists/listinfo/xen-devel > > > ------------------------------------------------------- > SF email is sponsored by - The IT Product Guide > Read honest & candid reviews on hundreds of IT Products from real users. > Discover which products truly live up to the hype. Start reading now. > http://ads.osdn.com/?ad_id=6595&alloc_id=14396&op=click > _______________________________________________ > Xen-devel mailing list > Xen-devel@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/xen-devel------------------------------------------------------- SF email is sponsored by - The IT Product Guide Read honest & candid reviews on hundreds of IT Products from real users. Discover which products truly live up to the hype. Start reading now. http://ads.osdn.com/?ad_id=6595&alloc_id=14396&op=click _______________________________________________ Xen-devel mailing list Xen-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/xen-devel
Keir Fraser
2005-Mar-10 19:44 UTC
Re: [Xen-devel] out-of-memory problem when restoring ballooned domains
On 10 Mar 2005, at 18:54, Lars Rasmusson wrote:> So all domains have 128 Mb, and xen seems to count the memory fine... > > (FYI I''m using xen-2.0-testing, checked out from bitkeeper this > morning)Very odd. Does /var/xen/xend-debug.log contain anything interesting? We''ll have to see if we can reproduce this -- my guess would be a tools hiccup as xen seems to be dealing with the scenario as expected. -- Keir ------------------------------------------------------- SF email is sponsored by - The IT Product Guide Read honest & candid reviews on hundreds of IT Products from real users. Discover which products truly live up to the hype. Start reading now. http://ads.osdn.com/?ad_id=6595&alloc_id=14396&op=click _______________________________________________ Xen-devel mailing list Xen-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/xen-devel
Lars Rasmusson
2005-Mar-10 20:54 UTC
Re: [Xen-devel] out-of-memory problem when restoring ballooned domains
The /var/log/xend.log gets these three lines added when I have restored t3 and t2, and try to restore t1 [2005-03-10 12:43:43 xend] INFO (XendMigrate:413) restore BEGIN: [''restore'', [''id'', ''2''], [''file'', ''/home/testlars/t1.saved'']] [2005-03-10 12:43:44 xend] ERROR (SrvBase:162) op=restore: 1 None Nothing is written into /var/log/xend-debug.log /Lars On Thu, 2005-03-10 at 19:44 +0000, Keir Fraser wrote:> On 10 Mar 2005, at 18:54, Lars Rasmusson wrote: > > > So all domains have 128 Mb, and xen seems to count the memory fine... > > > > (FYI I''m using xen-2.0-testing, checked out from bitkeeper this > > morning) > > Very odd. Does /var/xen/xend-debug.log contain anything interesting? > We''ll have to see if we can reproduce this -- my guess would be a tools > hiccup as xen seems to be dealing with the scenario as expected. > > -- Keir >------------------------------------------------------- SF email is sponsored by - The IT Product Guide Read honest & candid reviews on hundreds of IT Products from real users. Discover which products truly live up to the hype. Start reading now. http://ads.osdn.com/?ad_id=6595&alloc_id=14396&op=click _______________________________________________ Xen-devel mailing list Xen-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/xen-devel