Hi, what is minimal recommended memory reservation for domain0? It won''t run any services apart from sshd and xend and will provide files from /home (ext3) to other domains as their block devices. Machine is 466MHz Celeron with 256MB of RAM, UDMA/33 IDE interface, and will run about 5 other domains, so less is more ;-). TIA, j. ------------------------------------------------------- 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://productguide.itmanagersjournal.com/ _______________________________________________ Xen-devel mailing list Xen-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/xen-devel
> Hi, > what is minimal recommended memory reservation for domain0? It won''t run > any services apart from sshd and xend and will provide files from /home > (ext3) to other domains as their block devices. Machine is 466MHz > Celeron with 256MB of RAM, UDMA/33 IDE interface, and will run about 5 > other domains, so less is more ;-).Boot it with 64MB and then use the balloon driver to crank it down a bit. Give it a swap file to be on the safe side. Ian ------------------------------------------------------- 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://productguide.itmanagersjournal.com/ _______________________________________________ Xen-devel mailing list Xen-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/xen-devel
>>Hi, >>what is minimal recommended memory reservation for domain0? It won''t run >>any services apart from sshd and xend and will provide files from /home >>(ext3) to other domains as their block devices. Machine is 466MHz >>Celeron with 256MB of RAM, UDMA/33 IDE interface, and will run about 5 >>other domains, so less is more ;-). > > > Boot it with 64MB and then use the balloon driver to crank it > down a bit. Give it a swap file to be on the safe side.Thanks, but what do you think about 32MB? j. ------------------------------------------------------- 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://productguide.itmanagersjournal.com/ _______________________________________________ Xen-devel mailing list Xen-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/xen-devel
>>Hi, >>what is minimal recommended memory reservation for domain0? It won''t run >>any services apart from sshd and xend and will provide files from /home >>(ext3) to other domains as their block devices. Machine is 466MHz >>Celeron with 256MB of RAM, UDMA/33 IDE interface, and will run about 5 >>other domains, so less is more ;-). > > > Boot it with 64MB and then use the balloon driver to crank it > down a bit. Give it a swap file to be on the safe side.Just a small question - if I use `xm balloon Domain-0 64`, `xm info` reports correct amount of memory as free, but `free` says that domain0 has still $original_memory_size total, but used memory grows up, is it correct? (total, used, free, shared, buffers, cached) # free | grep Mem Mem: 116692 29056 87636 0 460 9600 # xm info | grep memory memory : 255 free_memory : 126 # xm balloon Domain-0 64 # free | grep Mem Mem: 116692 83536 33156 0 460 9600 # xm info | grep memory memory : 255 free_memory : 179 TIA, j. ------------------------------------------------------- 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://productguide.itmanagersjournal.com/ _______________________________________________ Xen-devel mailing list Xen-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/xen-devel
> >>Hi, > >>what is minimal recommended memory reservation for domain0? It won''t run > >>any services apart from sshd and xend and will provide files from /home > >>(ext3) to other domains as their block devices. Machine is 466MHz > >>Celeron with 256MB of RAM, UDMA/33 IDE interface, and will run about 5 > >>other domains, so less is more ;-). > > > > > > Boot it with 64MB and then use the balloon driver to crank it > > down a bit. Give it a swap file to be on the safe side. > > Just a small question - if I use `xm balloon Domain-0 64`, `xm info` > reports correct amount of memory as free, but `free` says that domain0 > has still $original_memory_size total, but used memory grows up, is it > correct?>From the point of view of the kernel, ballooned memory is actually "inuse". This is because the balloon is inflated by requesting memory from the kernel allocator -- the kernel assumes this memory is in use by the balloon driver, when in fact it is returned to Xen. So, ''free'' and ''cat /proc/meminfo'' will both mislead you. You need to subtract the balloon size from the ''total memory'' field to find out how much memory is *really* in use by the domain. -- Keir> (total, used, free, shared, buffers, cached) > # free | grep Mem > Mem: 116692 29056 87636 0 460 9600 > # xm info | grep memory > memory : 255 > free_memory : 126 > # xm balloon Domain-0 64 > # free | grep Mem > Mem: 116692 83536 33156 0 460 9600 > # xm info | grep memory > memory : 255 > free_memory : 179 > > TIA, > j. > > > > ------------------------------------------------------- > 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://productguide.itmanagersjournal.com/ > _______________________________________________ > 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://productguide.itmanagersjournal.com/ _______________________________________________ Xen-devel mailing list Xen-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/xen-devel
> From the point of view of the kernel, ballooned memory is actually "in > use". This is because the balloon is inflated by requesting memory > from the kernel allocator -- the kernel assumes this memory is in use > by the balloon driver, when in fact it is returned to Xen.Thanks. Is this true also for other domains than dom0? j. ------------------------------------------------------- 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://productguide.itmanagersjournal.com/ _______________________________________________ Xen-devel mailing list Xen-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/xen-devel
> > From the point of view of the kernel, ballooned memory is actually "in > > use". This is because the balloon is inflated by requesting memory > > from the kernel allocator -- the kernel assumes this memory is in use > > by the balloon driver, when in fact it is returned to Xen. > > Thanks. Is this true also for other domains than dom0? > > j. >This is true in any context you use a balloon driver. Dom0 or DomU. -- 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://productguide.itmanagersjournal.com/ _______________________________________________ Xen-devel mailing list Xen-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/xen-devel
>>> what is minimal recommended memory reservation for domain0? It won''t> Thanks, but what do you think about 32MB?I had serious problems with low-memory domain0. It caused problems with the backend of the block devices of other domains (those domains got I/O errors). I would not go below 64 MB, unless maybe by tweaking VM "will to swap" to be sure to have enough kernel memory available at anytime. ------------------------------------------------------- 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://productguide.itmanagersjournal.com/ _______________________________________________ Xen-devel mailing list Xen-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/xen-devel
Jérôme Petazzoni wrote:>> Thanks, but what do you think about 32MB? > > > I had serious problems with low-memory domain0. It caused problems with > the backend of the block devices of other domains (those domains got I/O > errors). I would not go below 64 MB, unless maybe by tweaking VM "will > to swap" to be sure to have enough kernel memory available at anytime.Thanks for feedback. I''m using file-backed VBDs (ie. domains are using files stored under domain0''s filesystem). BTW, what is the lowest-memory-hungry filesystem for this usage? Or should be something like LVM better? TIA, jkt -- cd /local/pub && more beer > /dev/mouth ------------------------------------------------------- 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://productguide.itmanagersjournal.com/ _______________________________________________ Xen-devel mailing list Xen-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/xen-devel