Re: Requesting clarification on Vacuuming/Freezing behaviour

Thanks Heikki. I misunderstood things. Especially the comment in log_heap_freeze misled me.<br /><br /><div
class="gmail_quote">OnDec 17, 2007 1:39 PM, Heikki Linnakangas <<a
href="mailto:heikki@enterprisedb.com">heikki@enterprisedb.com</a>> wrote:<br /><blockquote class="gmail_quote"
style="border-left:1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;"><div
class="Ih2E3d">GokulakannanSomasundaram wrote:<br />> a) When i was looking at the code for freezing heap tuples, i
foundout the <br />> following. While freezing we log the complete block(not just the tuples we<br />> froze).<br
/>>b) Again after removing the dead tuples and fragmentation, we log the<br />> complete block.<br /><br
/></div>Umm,no we don't. In log_heap_freeze, we log an array of offsets, of <br />those tuples that were frozen.<br
/><br/>Perhaps you're been confused by full page writes? If a block hasn't been<br />modified by last checkpoint, then
wedo log the whole page for any<br />operation, including vacuuming and freezing. (except setting hint bits). <br
/><fontcolor="#888888"><br />--<br />   Heikki Linnakangas<br />   EnterpriseDB   <a href="http://www.enterprisedb.com"
target="_blank">http://www.enterprisedb.com</a><br/></font></blockquote></div><br /><br clear="all" /><br />-- <br
/>Thanks,<br/>Gokul.<br />CertoSQL Project,<br />Allied Solution Group.<br />(<a
href="http://www.alliedgroups.com">www.alliedgroups.com</a>)