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<DIV>SELECT pg_size_pretty(pg_database_size(current_database()))</DIV>
<DIV>-> 1198MB</DIV>
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<DIV>> Making Slony scale like this is a non-starter, I would think.</DIV>
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<DIV>Can it cascade?:</DIV>
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<DIV>Master</DIV>
<DIV> |-Regional Master 1</DIV>
<DIV> | |-Slave1.1</DIV>
<DIV> | |-Slave1.2</DIV>
<DIV> | -Slave 1.3</DIV>
<DIV> |-Regional Master 2</DIV>
<DIV> | |-Slave 2.1</DIV>
<DIV> | |-Slave 2.2</DIV>
<DIV>...<BR><BR> </DIV>Dave Stevenson<BR>dave.stevenson@pacbell.net
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<B><SPAN style="FONT-WEIGHT: bold">From:</SPAN></B> Peter Geoghegan <peter.geoghegan86@gmail.com><BR><B><SPAN style="FONT-WEIGHT: bold">To:</SPAN></B> Dave Stevenson <dave.stevenson@pacbell.net><BR><B><SPAN style="FONT-WEIGHT: bold">Cc:</SPAN></B> Michael Squires <msquires@whitepages.com>; slony1-general@lists.slony.info<BR><B><SPAN style="FONT-WEIGHT: bold">Sent:</SPAN></B> Thu, February 25, 2010 8:44:29 AM<BR><B><SPAN style="FONT-WEIGHT: bold">Subject:</SPAN></B> Re: [Slony1-general] Is Slony for me?<BR></FONT><BR>> Not sure exactly how to measure this. After installing PostgreSQL to a<BR>> new machine, the 'data' directory is 32MB. I then restore my db from backup,<BR>> the data directory is 1.31GB. However, the .backup file from which the db<BR>> was restored is only 91MB.<BR><BR>To determine the size of your database, do this while connected to it:<BR>SELECT
pg_size_pretty(pg_database_size(current_database()))<BR><BR>> Maybe up to a few dozen or so eventually.<BR><BR>What you must understand is that slony's communication overhead with<BR>respect to the number of nodes increases quadratically; Every time you<BR>double the number of nodes, you quadruple the communication overhead.<BR>According to the docs, "Up to a half dozen nodes seems pretty<BR>reasonable". I'm not sure what the record is for number of slony nodes<BR>in a single cluster, but I suspect it is more than 6 but quite a bit<BR>less than several dozen. Making Slony scale like this is a<BR>non-starter, I would think.<BR><BR>Regards,<BR>Peter Geoghegan<BR></DIV></DIV></div></body></html>