Xen2 vs Xen3: features and stability?

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Hi,

I've been running xen2 with great success for quite some
time but I  
realize its days are numbered. So when evaluating making the
leap for  
xen3 I notice

a) that I haven't found a comparision between the two
anywhere. There  
are bits here and there, like SMP domU's requiring xen3 and
PCI  
access AFAIK requiring xen2, but no comprehensive summary.
If there  
is such a document anywhere I'd much appreciate a pointer
(and yes, I  
realize that a Linux-centric document is likely to point at
features  
not yet available for NetBSD, and that's fine too, I can
sort through  
that).

b) what's the general feeling as to production worthiness of
the xen3  
stuff? As stable as xen2 (which is working just great for
me, and I  
use it for a number of dom0's and dozens of domU's of
different  
shapes and forms)?

In general, as I don't need SMP at all, my gut feeling is
that  
there's no real rush to change...

Regards,

Johan

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Hmm.   I've mostly moved off of my NetBSD 3 (xen2) Dom0s
because while 
once up, they are rock-solid, the xend daemon doesn't seem
so stable; 
after adding 10 or 12 DomUs, the system does not allow me to
startup or 
shutdown any more guests.  Also, support for linux 2.6 DomU
kernels is a 
requirement in my environment.

That said, the difference in uptime between my Linux Xen3
Dom0s and my 
rock-solid NetBSD Xen2 Dom0 is rather shocking.

linux/Xen3:
lscauburn:~$ uptime
  10:12:38 up 20 days, 11:02,  7 users,  load average: 0.00,
0.02, 0.00

NetBSD/Xen2:
137:  uptime
10:00AM  up 121 days, 19:41, 5 users, load averages: 5.56,
4.34, 4.09

137:  uname -a
NetBSD 137 3.0.1 NetBSD 3.0.1 (amy-XEN0) #1: Wed Jul 12
02:33:02 PDT 2006 
lsc:/usr/obj/sys/arch/i386/compile/amy-XEN0 i386

(The NetBSD box is the only one that meets any kind of
reasonable SLA)

so yes, I am strongly considering moving to NetBSD4; the big
problem with 
Xen3 is that it seems to still be something of a moving
target (changes 
were made between 3.0.2-2 and 3.0.3 that broke NetBSD and
FreeBSD DomU
support... NetBSD support is fixed now in -current and 4.0)

Of course, the other option is to put the effort into
figuring out what's 
wrong with xen2-  at least then the specification isn't
going to move out 
from under you;  there is significant demand for stable
NetBSD/FreeBSD 
virtual servers.


On Wed, 22 Nov 2006, Johan Ihren wrote:
> -----BEGIN PGP SIGNED MESSAGE-----
> Hash: SHA1
>
> Hi,
>
> I've been running xen2 with great success for quite
some time but I realize 
> its days are numbered. So when evaluating making the
leap for xen3 I notice
>
> a) that I haven't found a comparision between the two
anywhere. There are 
> bits here and there, like SMP domU's requiring xen3 and
PCI access AFAIK 
> requiring xen2, but no comprehensive summary. If there
is such a document 
> anywhere I'd much appreciate a pointer (and yes, I
realize that a 
> Linux-centric document is likely to point at features
not yet available for 
> NetBSD, and that's fine too, I can sort through that).
>
> b) what's the general feeling as to production
worthiness of the xen3 stuff? 
> As stable as xen2 (which is working just great for me,
and I use it for a 
> number of dom0's and dozens of domU's of different
shapes and forms)?
>
> In general, as I don't need SMP at all, my gut feeling
is that there's no 
> real rush to change...
>
> Regards,
>
> Johan
>
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> Version: GnuPG v1.4.5 (Darwin)
>
>
iD8DBQFFZGoFKJmr+nqSTbYRAr/YAJ9tMFmew7+4dPQmGqNtUWCYCaev2gCf
eecZ
> 4FBG+hixBm7i94iy3kqTrQI=
> =ghdM
> -----END PGP SIGNATURE-----

Hmm.   I've mostly moved off of my NetBSD 3 (xen2) Dom0s
because while 
once up, they are rock-solid, the xend daemon doesn't seem
so stable; 
after adding 10 or 12 DomUs, the system does not allow me to
startup or 
shutdown any more guests.  Also, support for linux 2.6 DomU
kernels is a 
requirement in my environment.

That said, the difference in uptime between my Linux Xen3
Dom0s and my 
rock-solid NetBSD Xen2 Dom0 is rather shocking.

linux/Xen3:
lscauburn:~$ uptime
  10:12:38 up 20 days, 11:02,  7 users,  load average: 0.00,
0.02, 0.00

NetBSD/Xen2:
137:  uptime
10:00AM  up 121 days, 19:41, 5 users, load averages: 5.56,
4.34, 4.09

137:  uname -a
NetBSD 137 3.0.1 NetBSD 3.0.1 (amy-XEN0) #1: Wed Jul 12
02:33:02 PDT 2006 
lsc:/usr/obj/sys/arch/i386/compile/amy-XEN0 i386

(The NetBSD box is the only one that meets any kind of
reasonable SLA)

so yes, I am strongly considering moving to NetBSD4; the big
problem with 
Xen3 is that it seems to still be something of a moving
target (changes 
were made between 3.0.2-2 and 3.0.3 that broke NetBSD and
FreeBSD DomU
support... NetBSD support is fixed now in -current and 4.0)

Of course, the other option is to put the effort into
figuring out what's 
wrong with xen2-  at least then the specification isn't
going to move out 
from under you;  there is significant demand for stable
NetBSD/FreeBSD 
virtual servers.


On Wed, 22 Nov 2006, Johan Ihren wrote:
> -----BEGIN PGP SIGNED MESSAGE-----
> Hash: SHA1
>
> Hi,
>
> I've been running xen2 with great success for quite
some time but I realize 
> its days are numbered. So when evaluating making the
leap for xen3 I notice
>
> a) that I haven't found a comparision between the two
anywhere. There are 
> bits here and there, like SMP domU's requiring xen3 and
PCI access AFAIK 
> requiring xen2, but no comprehensive summary. If there
is such a document 
> anywhere I'd much appreciate a pointer (and yes, I
realize that a 
> Linux-centric document is likely to point at features
not yet available for 
> NetBSD, and that's fine too, I can sort through that).
>
> b) what's the general feeling as to production
worthiness of the xen3 stuff? 
> As stable as xen2 (which is working just great for me,
and I use it for a 
> number of dom0's and dozens of domU's of different
shapes and forms)?
>
> In general, as I don't need SMP at all, my gut feeling
is that there's no 
> real rush to change...
>
> Regards,
>
> Johan
>
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> Version: GnuPG v1.4.5 (Darwin)
>
>
iD8DBQFFZGoFKJmr+nqSTbYRAr/YAJ9tMFmew7+4dPQmGqNtUWCYCaev2gCf
eecZ
> 4FBG+hixBm7i94iy3kqTrQI=
> =ghdM
> -----END PGP SIGNATURE-----

On Wed, Nov 22, 2006 at 10:31:44AM -0800, Luke Crawford
wrote:
> [...]
> 
> so yes, I am strongly considering moving to NetBSD4;
the big problem with 
> Xen3 is that it seems to still be something of a moving
target (changes 
> were made between 3.0.2-2 and 3.0.3 that broke NetBSD
and FreeBSD DomU
> support... NetBSD support is fixed now in -current and
4.0)

and 3.1 

> 
> Of course, the other option is to put the effort into
figuring out what's 
> wrong with xen2-  at least then the specification isn't
going to move out 
> from under you;  there is significant demand for stable
NetBSD/FreeBSD 
> virtual servers.

Overall the Xen-3 tools are much better; also it doesn't use
wide-open
TCP ports without any kind of authentification which is a
big step forward.
There is also HVM which is great if your hardware supports
it.

-- 
Manuel Bouyer <bouyerantioche.eu.org>
     NetBSD: 26 ans d'experience feront toujours la
difference
--

On Wed, Nov 22, 2006 at 10:31:44AM -0800, Luke Crawford
wrote:
> [...]
> 
> so yes, I am strongly considering moving to NetBSD4;
the big problem with 
> Xen3 is that it seems to still be something of a moving
target (changes 
> were made between 3.0.2-2 and 3.0.3 that broke NetBSD
and FreeBSD DomU
> support... NetBSD support is fixed now in -current and
4.0)

and 3.1 

> 
> Of course, the other option is to put the effort into
figuring out what's 
> wrong with xen2-  at least then the specification isn't
going to move out 
> from under you;  there is significant demand for stable
NetBSD/FreeBSD 
> virtual servers.

Overall the Xen-3 tools are much better; also it doesn't use
wide-open
TCP ports without any kind of authentification which is a
big step forward.
There is also HVM which is great if your hardware supports
it.

-- 
Manuel Bouyer <bouyerantioche.eu.org>
     NetBSD: 26 ans d'experience feront toujours la
difference
--

> b) what's the general feeling as to production
worthiness of the xen3
> stuff? As stable as xen2 (which is working just great
for me, and I
> use it for a number of dom0's and dozens of domU's of
different
> shapes and forms)?

I have been using a NetBSD Xen 2 Dom 0/ Multiple Dom U setup
for
around 10 months at home with absolutely no problems what so
ever.
I've been contemplating upgrading to Xen 3, but have been
waiting to
hear a few success stories before making the leap.

Elsewhere I run a Xen 3.0.2-2 Linux Dom-0  with around 10
different
Dom-U's covering Linux, NetBSD and FreeBSD. One of my NetBSD
dom-U's
on that Linux Xen 3 dom-0 has been running
"production" traffic and
has an uptime of 125 days, with just 1 problem - an apparent
random
networking lockup that was resolved with a simple ifconfig
bounce. So
from my experience certainly NetBSD Xen 3 Dom-U is stable.
The thing I
miss most in my home Xen 2 is the xm top command available
in Xen 3.

> b) what's the general feeling as to production
worthiness of the xen3
> stuff? As stable as xen2 (which is working just great
for me, and I
> use it for a number of dom0's and dozens of domU's of
different
> shapes and forms)?

I have been using a NetBSD Xen 2 Dom 0/ Multiple Dom U setup
for
around 10 months at home with absolutely no problems what so
ever.
I've been contemplating upgrading to Xen 3, but have been
waiting to
hear a few success stories before making the leap.

Elsewhere I run a Xen 3.0.2-2 Linux Dom-0  with around 10
different
Dom-U's covering Linux, NetBSD and FreeBSD. One of my NetBSD
dom-U's
on that Linux Xen 3 dom-0 has been running
"production" traffic and
has an uptime of 125 days, with just 1 problem - an apparent
random
networking lockup that was resolved with a simple ifconfig
bounce. So
from my experience certainly NetBSD Xen 3 Dom-U is stable.
The thing I
miss most in my home Xen 2 is the xm top command available
in Xen 3.

Chris Brookes wrote:
> The thing I miss most in my home Xen 2 is the xm top
command available
> in Xen 3.

I don't know what "xm top" does exactly as I
haven't tried Xen 3 yet but
maybe you should install pkgsrc/sysutils/xenconsole and run
"xcon"...

Martti

Chris Brookes wrote:
> The thing I miss most in my home Xen 2 is the xm top
command available
> in Xen 3.

I don't know what "xm top" does exactly as I
haven't tried Xen 3 yet but
maybe you should install pkgsrc/sysutils/xenconsole and run
"xcon"...

Martti

On Fri, Nov 24, 2006 at 08:18:22AM +0200, Martti Kuparinen
wrote:
> Chris Brookes wrote:
> > The thing I miss most in my home Xen 2 is the xm
top command available
> > in Xen 3.
> 
> I don't know what "xm top" does exactly
this: 

xentop - 12:32:30   Xen 3.0.3-0
4 domains: 1 running, 3 blocked, 0 paused, 0 crashed, 0
dying, 0 shutdown
Mem: 3144688k total, 1735624k used, 1409064k free    CPUs: 8

3000MHz
      NAME  STATE   CPU(sec) CPU(%)     MEM(k) MEM(%) 
MAXMEM(k) MAXMEM(%) VCPUS
 NETS NETTX(k) NETRX(k) VBDS   VBD_OO   VBD_RD   VBD_WR SSID
  Domain-0 -----r      11329    3.9     131068    4.2   no
limit       n/a     8
    0        0        0    0        0        0        0    0
      rock --b---       1254    0.1    1047056   33.3   
1048576      33.3     8
    0        0        0    0        0        0        0    0
     tango --b---     433291   12.8     261496    8.3    
262144       8.3     1
    0        0        0    0        0        0        0    0
   toccata --b---     423618   11.6     261584    8.3    
262144       8.3     1
    0        0        0    0        0        0        0    0

Collecting disk and network statistics is not implemented
yet; if somone
wants to do it he's welcome 

-- 
Manuel Bouyer, LIP6, Universite Paris VI.          
Manuel.Bouyerlip6.fr
     NetBSD: 26 ans d'experience feront toujours la
difference
--