Re: Still recommending daily vacuum...

Michael Paesold <mpaesold@gmx.at>

From: Michael Paesold <mpaesold@gmx.at>
To: Alvaro Herrera <alvherre@commandprompt.com>
Cc: Gregory Stark <stark@enterprisedb.com>, "Jim C. Nasby" <decibel@decibel.org>, "Joshua D. Drake" <jd@commandprompt.com>, Tom Lane <tgl@sss.pgh.pa.us>, pgsql-hackers@postgresql.org
Date: 2007-07-05T07:30:17Z
Lists: pgsql-hackers
Alvaro Herrera wrote:
> So what you are proposing above amounts to setting scale factor = 0.05.
> The threshold is unimportant -- in the case of a big table it matters
> not if it's 0 or 1000, it will be almost irrelevant in calculations.  In
> the case of small tables, then the table will be vacuumed in almost
> every iteration if the threshold is 0, which is fine because the table
> is small anyway.  So why not let the threshold be 0 and be done with it?

For very small tables, setting a threshold of 0 could mean a vacuum 
after every single row update (or every other row). I think that is just 
burning cycles. What about a threshold of 10 or 50, to have at least 
some sanity limit? Even though the cost of vacuum of a small table is 
low, it is still not free, IMHO, no?

Best Regards
Michael Paesold