Re: What X86/X64 OS's do we need coverage for?

On Fri, 6 Apr 2007, Matthew O'Connor wrote:

> Devrim Gndz wrote:
>> Hi,
>>
>> On Fri, 2007-04-06 at 01:23 -0400, Matthew T. O'Connor wrote:
>>> The other thing to consider is that CentOS 5 has Xen built right in,
>>> so you should be able run VMs without VMWare on it.
>>
>> ... if the kernel of the OS has Xen support, there will be no
>> performance penalty (only 2%-3%) (Para-virtualization). Otherwise, there
>> will be full-virtualization, and we should expect a performance loss
>> about 30% for each guest OS (like Windows).
>
> I may be wrong but I thought that the guest OS kernel only needs special
> support if the underlying CPU doesn't have virtualization support which
> pretty much all the new Intel and AMD chips have. No?
>
It doesn't matter as far as MY box is concerned. I use VMWare extensively
in my current $DAYJOB, and I want to be able to test/play with things related
to that as well. The box I'm building will be using the (free) VMWare Server
as it's virtualization platform.

I'd still like to hear from a Tom Lane or someone else on the project with what
X86 or X86_64 OS's we need coverage for.

LER

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--
Larry Rosenman http://www.lerctr.org/~ler
Phone: +1 512-248-2683 E-Mail: ler(at)lerctr(dot)org
US Mail: 430 Valona Loop, Round Rock, TX 78681-3893
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Date: Fri, 06 Apr 2007 16:08:53 +0200
From: Markus Schiltknecht <markus(at)bluegap(dot)ch>
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To: Simon Riggs <simon(at)2ndquadrant(dot)com>
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Subject: Re: Auto Partitioning
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Simon Riggs wrote:
> i.e. if we have partitions for each year (2001, 2002, 2003 2004, 2005,
> 2006, 2007) AND we have already proved that 2005 is excluded when we
> have a WHERE clause saying year >= 2006, then we should be able to use
> the ordering to prove that partitions for 2004 and before are also
> automatically excluded.

Provided you've set up the right constraints, the current
constraint_exclusion feature does exactly that, no?

> I'll think some more about the Merge node, but not right now.

I've looked at nodeAppend.c and nodeMergeJoin.c. Probably we can use
much of nodeMergeJoin, just without the join? Instead returning the
tuples as they are, but in the correct order. The nodeMergeJoin code can
only handle two inputs (a left and a right node), but it might be
beneficial to structure multiple merge nodes into a binary tree layout
anyway. (I'm guessing that might reduce the amount of comparisons needed).

What do you think?

Regards

Markus