Thread: 8.4 path to repair_frag()?

Hi all,

To satisfy my own curiosity, I was trying to find where 8.4 kicks into a backwards scan of the data file during
(auto-)vacuuming.

This appears to be repair_frag() in backend/commands/vacuum.c, but only appears to be called by a FULL vacuum.
Autovacuum,however, appears to explicitly only ever call a not-FULL vacuum, so I'm trying to see where and how it would
bepossible for autovacuum to trigger this operation.  Any pointers? 

Thanks,
Tom

Excerpts from Tom Lanyon's message of mié abr 18 12:44:11 -0300 2012:
> Hi all,
>
> To satisfy my own curiosity, I was trying to find where 8.4 kicks into a backwards scan of the data file during
(auto-)vacuuming.
>
> This appears to be repair_frag() in backend/commands/vacuum.c, but only appears to be called by a FULL vacuum.
Autovacuum,however, appears to explicitly only ever call a not-FULL vacuum, so I'm trying to see where and how it would
bepossible for autovacuum to trigger this operation.  Any pointers? 

See lazy_truncate_heap in vacuumlazy.c.

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