Actually difference is
http://archives.postgresql.org/pgsql-hackers/2011-02/msg00415.php
Merlin Moncure <mmoncure@gmail.com> Thursday 10 February 2011 08:48:26
> On Sat, Feb 5, 2011 at 4:59 PM, Radosław Smogura
>
> <rsmogura@softperience.eu> wrote:
> > Hi,
> >
> > I do performance tests against orignal JDBC driver and my version in
> > binary and in text mode. I saw strange results when I was reading
> > varchar values. Here is some output from simple benchmark
> >
> > Plain strings speed Execution: 8316582 , local: 2116608 ,
> > all: 10433190
> > Binary strings speed Execution: 9354613 , local: 2755949 ,
> > all: 12110562
> > Text NG strings speed Execution: 8346902 , local: 2704242 ,
> > all: 11051144
> >
> > Plain is standard JDBC driver, Binary is my version with binary transfer,
> > Text is my version with normal transfer. 1st column, "Execution" is time
> > spend on query execution this includes send, recivie proto message,
> > store it, etc, no conversion to output format. Values are in
> > nanoseconds.
> >
> > In new version I added some functionality, but routines to read parts in
> > "Execution" block are almost same for binary and text.
> >
> > But as you see the binary version is 10-20% slower then orginal, and my
> > text version, if I increase number of read records this proportion will
> > not change. I done many checks, against even "skip proto message
> > content" driver, end results was same 10-20% slower.
>
> Since there is basically zero difference in how *varchar* is handled
> in the database for the text or binary protocols (AFAIK, they use the
> same code), this is almost certainly an issue with the JDBC driver, or
> your benchmark application.
>
> merlin
