>>> On 30.04.12 at 13:21, Per Jessen <[email protected]> wrote: > I have two xen hosts - > > host1 is 32bit, 16Gb RAM, running 12.1+updates, kernel 3.1.9-1.4-xen.
Hardly - there's no (supported) 32-bit Xen on 12.1. > host2 is 64bit, 32Gb RAM, also 12.1+updates, kernel 3.3.0-2-xen. > > dom0 on host1 boots fine in 256Mb, but for host2 I need 512M. > It's not a problem as such, but I'm curious as to why? How can we know or even guess, when you neither tell us anything about the differences of the hosts beyond their bitness, nor describe (or even better provide hard data) in what way it fails with less than 512Mb. That said, I don't really see the point in this small a host - how would you expect any guests to run there (which after all is what you'd want to use Xen for)? > I've also noticed that the virtual footprints of a few processes > are significantly different from host1 to host2: > > Host2: > > PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND > 2769 root 20 0 705m 20m 1508 S 0 4.1 0:02.94 xend > 2768 root 20 0 123m 12m 784 S 0 2.5 0:00.00 xend > 2770 root 20 0 181m 7224 7052 S 0 1.4 0:00.31 blktapctrl > 1 root 20 0 37180 4160 1916 S 0 0.8 0:00.89 systemd > 2471 root 20 0 4094m 3848 2788 S 0 0.8 0:00.11 > console-kit-dae > 2543 root 20 0 184m 3052 2516 S 0 0.6 0:00.08 polkitd > 882 root 20 0 315m 1456 1032 S 0 0.3 0:00.13 rsyslogd > > Host1: > > PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND > 5023 root 20 0 71260 10m 1644 S 0 4.1 0:00.90 xend > 5022 root 20 0 13952 7788 836 S 0 2.9 0:00.00 xend > 2066 root 20 0 90160 3292 2644 S 0 1.2 0:00.06 > console-kit-dae > 2133 root 20 0 24304 2716 2328 S 0 1.0 0:00.60 polkitd > 1 root 20 0 5148 2548 1856 S 0 0.9 0:00.62 systemd > 735 root 20 0 40116 1260 948 S 0 0.5 0:00.10 rsyslogd > > > For instance, xend on host2 appears to have a virtual footprint > of more than 10 times that of xend on host1. Is this is really > just due to 32 vs 64bit architecture? Presumably not directly, but given the list of processes above I don't see the direct relation to Xen - apart from xend, all others aren't Xen specific, yet show similar patterns. For xend, given that it's a Python script, looking at Python's footprint in general would probably get you much further. Jan -- To unsubscribe, e-mail: [email protected] To contact the owner, e-mail: [email protected]
