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<TITLE>Sling less for speed</TITLE>
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<P>Slide 18 of 96</P>
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<H2>Sling less for speed</H2>
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<LI><H2>while(@row = $sth->fetchrow_array) { }
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<LI>one column: 51,155 fetches per second
<LI>20 columns: 24,032 fetches per second
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<LI><H2>while($row = $sth->fetchrow_arrayref) { }
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<LI>one column: 58,653 fetches per second - approximately 12% faster
<LI>20 columns: 49,390 fetches per second - approximately 51% faster
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<LI><H2>while($row = shift(@$rowcache) || shift(@{$rowcache=$sth->fetchall_arrayref(undef, $max_rows)})) { }
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<LI>one column: 348,140 fetches per second - by far the fastest!
<LI>20 columns: 42,128 fetches per second - now slower than fetchrow_arrayref!
<LI>Why? Balance time saved making fewer calls with time spent managing more memory
<LI>Do your own benchmarks to find what works best for your situations
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<LI><H2>Notes:
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<LI>Tests used DBD::mysql on 100,000 rows with fields 9 chars each. $max_rows=1000;
<LI>Time spent inside fetchrow_* method is approximately 0.000011s (~90,000 per second)</UL></UL></P>
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