Sigres -- Accelerating INSERT/UPDATE with UPS

Hi,

I have made a Sigres which accelerates INSERT/UPDATE on PostgreSQL using
UPS.
The philosophy of Sigres is considering a battery supplied memory as a
persistent device, instead of disk.
You can download it from http://sourceforge.jp/projects/sigres/ .

In my environment, Sigres is 7 times faster than PostgreSQL
(default(fsync=on))
in the maximum case (client concurrency is 2),
and it is also 10% faster PostgreSQL (fsync=off).

The magic lies in skipping XLogWrite() and ignoring WALWriteLock in
"xlog.c" in most cases.
The exception is calls from AdvanceXLInsertBuffer() in "xlog.c".
And, on each XLogFileClose(), openLogFile is fsynced() before close().
# In this point, Sigres is different from just simply setting fsync=off.

Although I think Sigres can be considered one of the future directions
of PostgreSQL,
I do not know whether this software can be accepted for business people
or not.
Could you please give me some comments if you have any interest ?

Best Regards,

--
Hideyuki Kawashima
Assistant Professor, University of Tsukuba