Re: asynchronous and vectorized execution

Cooled down then measured performance again.

I show you the true result briefly for now.

At Mon, 11 Jul 2016 19:07:22 +0900 (Tokyo Standard Time), Kyotaro HORIGUCHI <horiguchi(dot)kyotaro(at)lab(dot)ntt(dot)co(dot)jp> wrote in <20160711(dot)190722(dot)145849861(dot)horiguchi(dot)kyotaro(at)lab(dot)ntt(dot)co(dot)jp>
> Anyway I need some time to cool down..

I recalled that I put Makefile.custom that contains
CFLAGS="-O0". Removing that gave me a sainer result.

patched- -O2

table 10-average(ms) stddev runtime-diff from unpatched(%)
t0 441.78 0.32 3.4
pl 201.77 0.32 13.6
pf0 6619.22 18.99 -19.7
pf1 1800.72 32.72 -78.0
---
unpatched- -O2

t0 427.21 0.42
pl 177.54 0.25
pf0 8250.42 23.29
pf1 8206.02 12.91

==========

3% slower for local 1*seqscan (2-parallel)
14% slower for append-4*seqscan (no-prallel)
19% faster for append-4*foreignscan (all scans on one connection)
78% faster for append-4*foreignscan (scans have dedicate connection)

ExecProcNode might be able to be optimized a bit.
ExecAppend seems to need some fix.

Addition to the aboves, I will try reentrant ExecAsyncWaitForNode
or something.

regards,

--
Kyotaro Horiguchi
NTT Open Source Software Center