Since we have fysically moved our database, our development machines
experience much long startup times for mmbase, around the order of 3min.
I did some investigation and found a nice little speedup which will reduce
starting mmbase with 30 seconds. Not really groundbreaking but it helps!
mmbase/src/org/mmbase/storage/implementation/database/DatabaseStorageManager.java
this is the original code which gets called for each builder:
protected synchronized boolean exists(String tableName)
throws StorageException {
try {
getActiveConnection();
DatabaseMetaData metaData = activeConnection.getMetaData();
ResultSet res = metaData.getTables(null, null, tableName, null);
try {
boolean result = res.next();
return result;
} finally {
res.close();
}
} catch (Exception e) {
throw new StorageException(e.getMessage());
} finally {
releaseActiveConnection();
}
}
I did some digging and found our that the jdbc-spec says that wildcards ('%')
can be used to find out which tables are in the database. Well, you know where
this will lead to, so this is the proposed code:
static Set cache = null;
protected synchronized boolean exists(String tableName)
throws StorageException {
// cache
if(cache == null) {
try {
cache = new HashSet();
getActiveConnection();
DatabaseMetaData metaData = activeConnection.getMetaData();
ResultSet res =
metaData.getTables(null, null,
factory.getMMBase().getBaseName()+"_%", null);
try {
while(res.next())
cache.add(res.getString(3));
} finally {
res.close();
}
} catch(Exception e) {
throw new StorageException(e.getMessage());
} finally {
releaseActiveConnection();
}
}
return cache.contains(tableName);
}
I post this because I dont know if the original maintainer didn't use this
feature
with a reason.
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