Re: Some thoughts about i/o priorities and throttling vacuum

From: Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>
To: Alvaro Herrera <alvherre(at)dcc(dot)uchile(dot)cl>
Cc: Shridhar Daithankar <shridhar_daithankar(at)persistent(dot)co(dot)in>, pgsql-hackers(at)postgresql(dot)org
Subject: Re: Some thoughts about i/o priorities and throttling vacuum
Date: 2003-10-17 15:59:50
Message-ID: 23321.1066406390@sss.pgh.pa.us
Views: Raw Message | Whole Thread | Download mbox | Resend email
Thread:
Lists: pgsql-hackers

Alvaro Herrera <alvherre(at)dcc(dot)uchile(dot)cl> writes:
> The trick to keep in mind is that the XID comparison functions use
> "modulo" operations, _but_ there are special "frozen" XIDs that are
> always "committed" -- that's why a VACUUM FREEZE would relieve the table
> forever from this problem.

> (At least this is how I understand it -- I could be totally wrong here)

No, that's exactly correct.

regards, tom lane

In response to

Browse pgsql-hackers by date

  From Date Subject
Next Message Matthew T. O'Connor 2003-10-17 16:00:23 Re: Some thoughts about i/o priorities and throttling vacuum
Previous Message Tom Lane 2003-10-17 15:53:52 Re: Some thoughts about i/o priorities and throttling vacuum