[15:42] <inetpro> ahoi ubuntuland!
[15:47] <theblazehen> hi inetpro
[15:47] <inetpro> theblazehen: how are you doing?
[15:47] <theblazehen> Good and you inetpro ?
[15:47] <inetpro> all good thanks
[15:59] <inetpro> theblazehen: what can you tell me about running virtual machines with 32bit Ubuntu server on a 64bit KVM host environment?
[15:59] <inetpro> good idea / bad idea, or does it even make a difference?
[16:02] <theblazehen> inetpro: Depends on workload inside the VM
[16:03] <theblazehen> I'm assuming you won't be needing more than 4 GiB RAM inside the guest?
[16:04] <theblazehen> 32 bit will use 32 instead of 64 bit pointers, so less overhead there, but misses out on cool x64 features
[16:04] <theblazehen> Check out that top bit of https://en.wikipedia.org/wiki/X32_ABI for a TL;DR
[16:15] <MaNI> ubuntu doesn't  use x32 though does it, just standard x86 (i386)?
[16:19] <MaNI> note also that x32 (which sadly probably isn't what you will get) only limits to 4GiB per program, so you can still use more than 4GiB in total
[16:19] <inetpro> if I just need a server with less than 2GB of RAM surely 32bit will be more effective on resources?
[16:20] <inetpro> s/effective/efficient/
[16:23] <MaNI> sure, but if it's x86 it wastes half the registers and a bunch of other fancy cpu capabilities
[16:23] <MaNI> x32 is meant to be the compromise between the two - but I'm unaware of any mainstream binary distro offering it as an option
[16:24] <inetpro> hmm... and most developers now have 64bit, so I guess 64bit is probably safer to go as well?
[16:28] <MaNI> I would not expect much difference in terms of stability at this point
[16:28] <MaNI> either way
[16:32] <inetpro> thanks for the inputs 
[16:32] <theblazehen> "ubuntu doesn't use x32 though does it, just standard x86 (i386)?" MaNI Yeah, wasn't recommending it, it just had a great TL;DR of the (dis|)advantages of each
[16:33] <inetpro> am not sure what exactly is in this ISO ubuntu-14.04.5-server-i386.iso
[16:34] <theblazehen> inetpro: That's normal 32 bit
[16:34] <inetpro> I have a machine with that running, how do I check?
[16:34] <MaNI> i386 = normal 32 bit indeed
[16:34] <theblazehen> `uname -p`
[16:35] <inetpro> i686
[16:35] <MaNI> short version. x86 (i386/i486/i586/i686) can have smaller binaries and less memory but uses less of the CPU
[16:35] <MaNI> x86_64 uses all of the new cpu features, but often makes programs use more memory
[16:36] <MaNI> x32 is meant to be the best of both worlds but isn't really available for anyone who isn't a cutting edge power user to use
[16:36] <inetpro> MaNI: yah, that last point is the big problem going forward
[16:37] <MaNI> despite the above there are certain workloads where x86 can outperform x86_64, but for the most part x86_64 will perform better YMMV
[16:37] <theblazehen> 👍 Nice summary MaNI
[16:39] <MaNI> x86 binaries also tend to suffer in that they are built for the 'lowest common denominator' of x86 cpus - and x86 cpus date very far back. So they often don't take full advantage of some of the new x86 cpu features even... While x86_64 does not have such a long history so x86_64 binaries make use of more modern features
[16:40] <MaNI> but people who compile for themselves like myself can side step this (for example) - so it's hard to get proper comparisons even when you look at benchmarks etc.
[16:41] <theblazehen> afaik programs can do feature detection, and use faster instructions if they are available?
[16:42] <MaNI> some can certainly
[16:43] <MaNI> and especially things like video compression libraries generally do, much like facebook relationships "it's complicated" :(
[17:00] <inetpro> haha 
[18:26] <NeRoboto> Ubuntu!