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<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>I’m running postgresql 8.1.0 with postgis 1.0.4 on a
FC3 system, 3Ghz, 1 GB memory.</span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'> </span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>I am using COPY to fill a table that contains one postgis
geometry column.</span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'> </span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>With no geometry index, it takes about 45 seconds to COPY
one file.</span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'> </span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>If I add a geometry index, this time degrades. It
keeps getting worse as more records are</span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>added to the table. It was up to over three minutes
per file on my most recent test. If I let</span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>it run long enough, the time degrades to 7 or 8 minutes.</span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'> </span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>The problem is that each file contains about 5 – 10
minutes of data. Eventually, I want to</span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>add the data to the table in “real time”.
So the COPY needs to take less time than </span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>actually generating the data.</span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'> </span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>Here is the relevant section of my postgresql.conf.</span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'> </span></font></p>
<p class=MsoNormal><font size=2 face="Courier New"><span style='font-size:10.0pt;
font-family:"Courier New"'># - Memory -</span></font></p>
<p class=MsoNormal><font size=2 face="Courier New"><span style='font-size:10.0pt;
font-family:"Courier New"'> </span></font></p>
<p class=MsoNormal><font size=2 face="Courier New"><span style='font-size:10.0pt;
font-family:"Courier New"'>shared_buffers =
5000
# min 16 or max_connections*2, 8KB each</span></font></p>
<p class=MsoNormal><font size=2 face="Courier New"><span style='font-size:10.0pt;
font-family:"Courier New"'>#temp_buffers =
1000
# min 100, 8KB each</span></font></p>
<p class=MsoNormal><font size=2 face="Courier New"><span style='font-size:10.0pt;
font-family:"Courier New"'>#max_prepared_transactions =
5 # can be 0
or more</span></font></p>
<p class=MsoNormal><font size=2 face="Courier New"><span style='font-size:10.0pt;
font-family:"Courier New"'># note: increasing max_prepared_transactions costs
~600 bytes of shared memory</span></font></p>
<p class=MsoNormal><font size=2 face="Courier New"><span style='font-size:10.0pt;
font-family:"Courier New"'># per transaction slot, plus lock space (see max_locks_per_transaction).</span></font></p>
<p class=MsoNormal><font size=2 face="Courier New"><span style='font-size:10.0pt;
font-family:"Courier New"'>work_mem =
20000
# min 64, size in KB</span></font></p>
<p class=MsoNormal><font size=2 face="Courier New"><span style='font-size:10.0pt;
font-family:"Courier New"'>maintenance_work_mem =
20000 # min 1024, size in KB</span></font></p>
<p class=MsoNormal><font size=2 face="Courier New"><span style='font-size:10.0pt;
font-family:"Courier New"'>#max_stack_depth =
2048 #
min 100, size in KB</span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'> </span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>Any suggestions for improvement?</span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'> </span></font></p>
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