--On 20. September 2012 18:18:12 -0400 Tom Lane <tgl@sss.pgh.pa.us> wrote:
> If it were an actual TRUNCATE, yeah. But it could be a case of VACUUM
> truncating a now-empty table to zero blocks.
>
> But nothing like this would explain the OP's report that corruption is
> completely reproducible for him. So I like your theory about hash index
> use better. We really oughta get some WAL support in there.
We had a similar issue at a customer site. The server was shut down for
updating it from 9.1.4 to 9.1.5, after starting it again the log was
immediately cluttered with
ERROR: could not read block 251 in file "base/6447890/7843708": read only
0 of 8192 bytes
The index was a primary key on table with mostly INSERTS (only a few
hundred DELETEs, autovacuum didn't even bother to vacuum it yet and no
manual VACUUM). According to the customer, no DDL action takes place on
this specific table. The kernel didn't show any errors.
--
Thanks
Bernd