HOT patch - version 11

<br />Hi All,<br /><br />Please see the version 11 of HOT patch posted on -patches.<br /><br />The concept of marking
thepruned tuples with LP_DELETE and <br />reusing such tuples for subsequent UPDATEs has been removed<br />and replaced
witha simpler mechanism of repairing the page <br />fragmentation as and when possible.<br /><br clear="all" />The
logicof chain pruning has been simplified a lot. In addition, there<br />are fewer new WAL log records. We rather reuse
theexisting WAL<br />record types to log the operations. <br /><br />Few 4 hour DBT2 runs have confirmed that this
simplificationhasn't<br />taken away any performance gains, rather we are seeing better performance<br />with the
changes.The gain can be attributed to the fact that now more <br />HOT updates are possible even if the tuple length
changesbetween<br />updates (since we do the complete page defragmentation)<br /><br />The changes are mostly isolated
inthe above area apart from some<br />stray bug fixes. <br /><br />Thanks,<br />Pavan<br /><br />-- <br />Pavan
Deolasee<br/>EnterpriseDB     <a href="http://www.enterprisedb.com">http://www.enterprisedb.com</a>