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Re: bdb bad performance again (really need help)

--On Monday, November 10, 2003 8:10 AM +0100 Stefan Metzmacher <metze@metzemix.de> wrote:

We do not put our entire DB into memory, however, we do run a very large
cache (2.5GB).

The reason is essentially this -- If you do not have a sufficient cache
size, the system must read almost continuously from disk to answer
queries. This trashes the disk, and eventually has the end effect of
corrupting the database.

How can read operations corrupt the data base?

I don't explain it, I just know what has happened for us, and plenty of other sites as well. I think it is more that BDB's disk cache gets corrupted, more than the underlying database files.


Quanah Gibson-Mount
Principal Software Developer
ITSS/TSS/Computing Systems
ITSS/TSS/Infrastructure Operations
Stanford University
GnuPG Public Key: http://www.stanford.edu/~quanah/pgp.html