Control: found -1 4.6.1-1 Control: tag -1 + pending Hi,
Thorsten Alteholz wrote: > the file ./etc/xen-tools.conf of the source package, which will be > installed at /etc/xen-tools.conf, contains a default value of 128M > for the size of memory. > > This is no longer sufficient for current kernels in Stretch and > should be increased. I unfortunately can confirm that. I was able to boot reliably with 136 MB instead of 128 MB (i.e. 8 MB more). (With only 132 MB of RAM, it only worked occasionally.) Interestingly, afterwards, htop showed me 116 MB available RAM of which about 29 MB were used by the named OS (i.e. the kernel only needs about 12 MB of RAM — although the difference usually was 16 MB if I gave more RAM to the DomU): Mem[||||||||##********* 29.0M/116M] That's also what made my cry out loud: I expected that these 12 or 16 MB of RAM have risen to over 128 MB of RAM. I was not aware that there's another, only boot-related (and likely initramfs-related) limit. So given that 136 MB already suffices and there's much more RAM than I expected later available for the OS, I've risen that value in Git to 256 MB (not 384 MB as planned before): https://github.com/xen-tools/xen-tools/commit/7a3791d1aac6de24f7505aeef4caa64cf1173f5f. That should suffice for a while and still gives a very usable DomU for e.g. BIND or a lightweight webserver. (So yes, the new default is not the smallest possible number, but I don't think that VMs should have much RAM by default. I think or at least hope that 256 MB will work fine for quite a few years. Other similar changes I made: * Default swap size risen to 512 MB (i.e. twice the RAM). * Commented out maxmem example risen from 256 MB to 2 GB. What I'm currently still unsure is, if I should switch the default file system to ext4 instead of ext3. That will likely cause older releases to no more boot with default settings. But then again, being able to boot older, no more supported releases is nice, but not xen-tools' main purpose and all still supported distros should be able to work on ext4 file systems. So I'll probably do that switch. > As the kernel crashes with such a low value and due to the default value > "on_crash = 'restart'", such an image will reboot endlessly. For some reason I didn't ran into that. But I currently only have a Jessie based Dom0 to test. :-/ Regards, Axel -- ,''`. | Axel Beckert <a...@debian.org>, http://people.debian.org/~abe/ : :' : | Debian Developer, ftp.ch.debian.org Admin `. `' | 4096R: 2517 B724 C5F6 CA99 5329 6E61 2FF9 CD59 6126 16B5 `- | 1024D: F067 EA27 26B9 C3FC 1486 202E C09E 1D89 9593 0EDE
