Re: choice of i386 vs amd64 guest
Victor Sudakov wrote: > Paul Vixie wrote: >> for everything else, the larger register set on amd64 will matter more, >> and you should probably use a 64-bit guest. > > There is an opinion that 64-bit systems use up more resources than > 32-bit ones for the same tasks, it that not true? it's not true. only the size of a pointer can affect you, and only if your RAM will be mostly full of pointers, as it would be with BIND9. for a web server you'll notice no real difference between CPU modes. -- P Vixie ___ freebsd-virtualization@freebsd.org mailing list https://lists.freebsd.org/mailman/listinfo/freebsd-virtualization To unsubscribe, send any mail to "freebsd-virtualization-unsubscr...@freebsd.org"
Re: choice of i386 vs amd64 guest
On Tue, Oct 18, 2016 at 10:41 AM, Victor Sudakov wrote: > Paul Vixie wrote: >> >> > >> > When I must run several FreeBSD guests in bhyve, should I prefer i386 >> > or amd64 guests provided a guest will never need more than 2-3 GB of >> > RAM? >> >> if you're running bind9, the sizeof(void *) will dominate your heap >> size, and a 32-bit guest will be better overall, given that you don't >> need the larger addressing size. > > Those guests will be running web servers mostly. > >> >> for everything else, the larger register set on amd64 will matter more, >> and you should probably use a 64-bit guest. > > There is an opinion that 64-bit systems use up more resources than > 32-bit ones for the same tasks, it that not true? > Yes, in fact, it's not an opinion, it's a fact, the "issue" is that in amd64 pointers are 64bits wide, so take up twice as much space in memory as they would on 32-bit mode. So if your workload/datastructures are mainly manipulating lots of pointers you will see higher memory usage. On the other hand 64bit has larger register set and guaranteed presence of SSE2 instructions making it more suitable where more computations are taking place. > -- > Victor Sudakov, VAS4-RIPE, VAS47-RIPN > sip:suda...@sibptus.tomsk.ru > ___ > freebsd-virtualization@freebsd.org mailing list > https://lists.freebsd.org/mailman/listinfo/freebsd-virtualization > To unsubscribe, send any mail to > "freebsd-virtualization-unsubscr...@freebsd.org" ___ freebsd-virtualization@freebsd.org mailing list https://lists.freebsd.org/mailman/listinfo/freebsd-virtualization To unsubscribe, send any mail to "freebsd-virtualization-unsubscr...@freebsd.org"
Re: choice of i386 vs amd64 guest
Paul Vixie wrote: > > > > > When I must run several FreeBSD guests in bhyve, should I prefer i386 > > or amd64 guests provided a guest will never need more than 2-3 GB of > > RAM? > > if you're running bind9, the sizeof(void *) will dominate your heap > size, and a 32-bit guest will be better overall, given that you don't > need the larger addressing size. Those guests will be running web servers mostly. > > for everything else, the larger register set on amd64 will matter more, > and you should probably use a 64-bit guest. There is an opinion that 64-bit systems use up more resources than 32-bit ones for the same tasks, it that not true? -- Victor Sudakov, VAS4-RIPE, VAS47-RIPN sip:suda...@sibptus.tomsk.ru ___ freebsd-virtualization@freebsd.org mailing list https://lists.freebsd.org/mailman/listinfo/freebsd-virtualization To unsubscribe, send any mail to "freebsd-virtualization-unsubscr...@freebsd.org"
Re: choice of i386 vs amd64 guest
Victor Sudakov wrote: > Colleagues, > > When I must run several FreeBSD guests in bhyve, should I prefer i386 > or amd64 guests provided a guest will never need more than 2-3 GB of > RAM? if you're running bind9, the sizeof(void *) will dominate your heap size, and a 32-bit guest will be better overall, given that you don't need the larger addressing size. for everything else, the larger register set on amd64 will matter more, and you should probably use a 64-bit guest. -- P Vixie ___ freebsd-virtualization@freebsd.org mailing list https://lists.freebsd.org/mailman/listinfo/freebsd-virtualization To unsubscribe, send any mail to "freebsd-virtualization-unsubscr...@freebsd.org"
choice of i386 vs amd64 guest
Colleagues, When I must run several FreeBSD guests in bhyve, should I prefer i386 or amd64 guests provided a guest will never need more than 2-3 GB of RAM? The bhyve host is of course amd64. -- Victor Sudakov, VAS4-RIPE, VAS47-RIPN sip:suda...@sibptus.tomsk.ru ___ freebsd-virtualization@freebsd.org mailing list https://lists.freebsd.org/mailman/listinfo/freebsd-virtualization To unsubscribe, send any mail to "freebsd-virtualization-unsubscr...@freebsd.org"