On Mon, 23 Mar 2009, Laurent Wandrebeck wrote:
I thought about completely fair scheduler at first, but that one came
in around 2.6.21.
CFS showed up in 2.6.23.
I think that forcing the system to write down more often, and smaller
data just hides the problem, and doesn't correct it.
That's
marcin mank writes:
> I hit an interestinhg paper on n_distinct calculation:
> http://www.pittsburgh.intel-research.net/people/gibbons/papers/distinct-values-chapter.pdf
I don't think we're quite ready to make ANALYZE read every row of a
table in order to estimate n_distinct. It is an interestin
> I hit an interestinhg paper on n_distinct calculation:
>
> http://www.pittsburgh.intel-research.net/people/gibbons/papers/distinct-values-chapter.pdf
>
> the PCSA algorithm described there requires O(1) calculation per
> value. Page 22 describes what to do with updates streams.
>
> This I think (
> So the bottom line here is just that the estimated n_distinct is too
> low. We've seen before that the equation we use tends to do that more
> often than not. I doubt that consistently erring on the high side would
> be better though :-(. Estimating n_distinct from a limited sample of
> the po
2009/3/22 Greg Smith :
> On Fri, 20 Mar 2009, M. Edward (Ed) Borasky wrote:
>
>> I just discovered this on a LinkedIn user group:
>> http://bugzilla.kernel.org/show_bug.cgi?id=12309
>
> I would bet there's at least 3 different bugs in that one. That bug report
> got a lot of press via Slashdot a f
Kouber Saparev writes:
> Tom Lane wrote:
>> Hmph, that's still not real good. Ideally it should be estimating
>> *less* than the average frequency, because the estimate is made after
>> excluding all the most-common-values, which evidently 'kouber' is not
>> one of.
> I altered the statistics fo
On Fri, 20 Mar 2009, M. Edward (Ed) Borasky wrote:
I just discovered this on a LinkedIn user group:
http://bugzilla.kernel.org/show_bug.cgi?id=12309
I would bet there's at least 3 different bugs in that one. That bug
report got a lot of press via Slashdot a few months ago, and it's picked
a
On Sun, Mar 22, 2009 at 8:49 AM, Laurent Wandrebeck
wrote:
> 2009/3/21 M. Edward (Ed) Borasky :
>> I just discovered this on a LinkedIn user group:
>>
>> http://bugzilla.kernel.org/show_bug.cgi?id=12309
>>
>> Is anyone here seeing evidence of this in PostgreSQL??
> I've been hit by an I/O wait pro
2009/3/21 M. Edward (Ed) Borasky :
> I just discovered this on a LinkedIn user group:
>
> http://bugzilla.kernel.org/show_bug.cgi?id=12309
>
> Is anyone here seeing evidence of this in PostgreSQL??
I've been hit by an I/O wait problem, as described here:
https://bugzilla.redhat.com/show_bug.cgi?id=
