Re: BUG #5055: Invalid page header error

Craig Ringer wrote:
> PostgreSQL has to trust the hardware and the OS to do their jobs. If the
> OS is, unbeknownst to PostgreSQL, flipping the high bit in any byte

Might not even be the OS - it could be the stars (through cosmic rays).

http://www.eetimes.com/news/98/1012news/ibm.html
  '"This clearly indicates that because of cosmic rays,
   for every 256 Mbytes of memory, you'll get one soft
   error a month," said Tim Dell, senior design
   engineer for IBM Microelectronics. '

> The RAID controller might be "helpfully" "fixing" parity errors
> in a RAID 5 volume using garbage being returned by a failing disk
> during periodic RAID scrubbing.

If your raid controller doesn't have ECC memory, and if IBM's
right about those soft error stats, it might be doing more
harm than good.