I got an interesting question today from a customer which created a database on ODA. He selected the template odb-04 which shows 32GB Memory but got a database with a 16GB SGA\u2026 Is it due to the PGA size, a limitation in the system, the huge pages usage which is reached or even a bug?<\/p>\n
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Indeed, the answer is easier and funnier. If you look to the menu shown by OAKCLI while creating a database, you get something like that:<\/p>\n
Please select one of the following for Database Class [1 .. 6]:\n\n1 => odb-01s ( 1 cores , 4 GB memory)\n\n2 => odb-01 ( 1 cores , 8 GB memory)\n\n3 => odb-02 ( 2 cores , 16 GB memory)\n\n4 => odb-04 ( 4 cores , 32 GB memory)\n\n5 => odb-06 ( 6 cores , 48 GB memory)\n\n6 => odb-12 ( 12 cores , 96 GB memory)\n\n4\n\nSelected value is : odb-04 ( 4 cores , 32 GB memory)<\/pre>\n<\/p>\n
So using the template odb-04 seems to use 32GB memory for the newly created database. However looking to what OAKCLI really does shows that the reality is a bit different. Following all files\/scripts which are called by OAKCLI at execution, we come to following file<\/p>\n
\/opt\/oracle\/oak\/lib\/oakutilslib\/DbSizingValues.pm<\/pre>\n<\/p>\n
This script contains the definition of the DBCA template used including the memory definition<\/p>\n
my $sga_size = $memory * $dbTypes{$dbtypeid}{sga_factor};\nmy $pga_size = $memory * $dbTypes{$dbtypeid}{pga_factor};<\/pre>\nSo the memory value is multiplied by a factor depending on the database type. Looking in the same script we find both information:<\/p>\n
my %dbTemplates =\n\n ( 1 => { name => 'odb-01s', cpus => 1, sfactor => 0.5},\n\n 2 => { name => 'odb-01', cpus => 1 },\n\n 3 => { name => 'odb-02', cpus => 2 },\n\n 4 => { name => 'odb-04', cpus => 4 },\n\n 5 => { name => 'odb-06', cpus => 6 },\n\n 6 => { name => 'odb-12', cpus => 12 },\n\n 7 => { name => 'odb-16', cpus => 16 },\n\n 8 => { name => 'odb-24', cpus => 24 },\n\n 9 => { name => 'odb-32', cpus => 32 },\n\n 10 => { name => 'odb-36', cpus => 36 }\n\n );\n\nmy %dbTypes =\n\n ( 1 => { name => 'OLTP', template_name => 'OAK_oltp.dbt', sga_factor => 0.5, pga_factor => 0.25 },\n\n 2 => { name => 'DSS', template_name => 'OAK_dss.dbt', sga_factor => 0.25, pga_factor => 0.50 },\n\n 3 => { name => 'In-Memory', template_name => 'OAK_oltp.dbt',sga_factor => 0.25, pga_factor => 0.25, in_mem_factor=>0.25, only12c=> 1}\n\n );<\/pre>\n<\/p>\n