Message-ID: <461A9C86.4000008@mochima.com>
Date: Mon, 09 Apr 2007 16:05:26 -0400
From: Carlos Moreno <moreno_pg@mochima.com>
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To: PostgreSQL Performance <pgsql-performance@postgresql.org>
Subject: Please humor me ... 
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And by the subject, I mean:  please provide a "factual" answer, as opposed
to the more or less obvious answer which would be "no one in their sane
mind would even consider doing such thing"  :-)

1) Would it be possible to entirely disable WAL?  (something like setting a
symlink so that pg_xlog points to /dev/null, perhaps?)

2) What would be the real implications of doing that?

As I understand it, the WAL provide some sort of redundancy for fault-
tolerance purposes;  if my understanding is correct, then what kind of
data loss are we talking about if I entirely disabled WAL and the machine
running the DB cluster were to crash/freeze?  What about a physical
reboot (either a UPSless power-down, or someone pressing the reset
button)?  Or are we talking about the entire DB cluster possibly
becoming corrupt beyond repair with 0% of the data being recoverable?


Again, please bear with me ...  I do know and understand the "no one in
their sane mind would even consider doing such thing"  aspect ...  I'm
for now interested in knowing more in detail the real facts behind this
feature --- allow me to think outside the box for a little while  :-)


Thanks,

Carlos
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