Re: Severe performance degradation when using the 9.2-1000 JDBC 4 driver

On 10/18/2012 05:17 PM, Mikko Tiihonen wrote:
> I think the DNS lookup is part of the JDBC failover connection patch that I created.
> I initially used a InetSocketAddress.getHostString() that does not do any DNS lookups, but since that method was
addedin Java7 I had to revert to getHostName() method which does. 
>
> I see following options:

0) Revert the JDBC failover patch or require a connection parameter to
enable it

> 1) modify the code so that is uses reflection and if Java7 is detected it will use the no-lookup method

Gah! no! Not only will this not work in most SecurityManager contexts,
but it's slow and horrid.

> 2) wait 4 months until Oracle drops Java6 support (Java6 was supposed to be EOL already few months back) and use the
no-lookupvariant 

... then another two years or so until it's actually adopted. People
still use Java 1.4, and 1.5 remains very wide-spread. Sadly.

> 3) let the code stay as is and let users fix their dns servers

While sometimes reasonable, in this case it's also a performance
regression for functionality most will never need, so -1 to that.

--
Craig Ringer