On 28.08.2012 22:50, Ants Aasma wrote:
On Tue, Aug 28, 2012 at 9:42 PM, Tom Lane wrote:
Seems like that's down to the CPU not doing "rep stosq" particularly
quickly, which might well be chip-specific.
AMD optimization manual[1] states the following:
For repeat counts of less than 4k, ex
On Tue, Aug 28, 2012 at 9:42 PM, Tom Lane wrote:
> Seems like that's down to the CPU not doing "rep stosq" particularly
> quickly, which might well be chip-specific.
AMD optimization manual[1] states the following:
For repeat counts of less than 4k, expand REP string instructions
into equiva
Heikki Linnakangas writes:
> On 28.08.2012 20:30, Tom Lane wrote:
>> Fascinating. I'd been of the opinion that modern compilers would inline
>> memset() for themselves and MemSet was probably not better than what the
>> compiler could do these days. What platform are you testing on?
> x64, gcc
On 28.08.2012 20:30, Tom Lane wrote:
Heikki Linnakangas writes:
Drilling into the profile, I came up with three little optimizations:
1. Within spgdoinsert, a significant portion of the CPU time is spent on
line 2033 in spgdoinsert.c:
memset(&out, 0, sizeof(out));
That zeroes out a sma
Heikki Linnakangas writes:
> Drilling into the profile, I came up with three little optimizations:
> 1. Within spgdoinsert, a significant portion of the CPU time is spent on
> line 2033 in spgdoinsert.c:
> memset(&out, 0, sizeof(out));
> That zeroes out a small struct allocated in the stack. R
I did some performance testing of building an SP-GiST index, with the
new range type SP-GiST opclass. There's some low-hanging fruit there, I
was able to reduce the index build time on a simple test case by about
20% with a few small changes.
I created a test table with:
create table range_te
