Re: Load distributed checkpoint

"Takayuki Tsunakawa" <tsunakawa.takay@jp.fujitsu.com> wrote:

> I performed some simple tests, and I'll show the results below.

> (1) The default case
> 235  80  226 77  240
> (2) No write case
> 242  250  244  253  280
> (3) No checkpoint case
> 229  252  256  292  276
> (4) No fsync() case
> 236  112  215  216  221
> (5) No write by PostgreSQL, but fsync() by another program case
> 9  223  260  283  292
> (6) case (5) + O_SYNC by write_fsync
> 97  114  126  112  125
> (7) O_SYNC case
> 182  103  41  50  74

I posted a patch to PATCHES. Please try out it.
It does write() smoothly, but fsync() at a burst.
I suppose the result will be between (3) and (5).

Regards,
---
ITAGAKI Takahiro
NTT Open Source Software Center