Strange. I was under the impression the TCP stack (on Unix at least) would switch you to IPC when it realized you were on the local loopback. Of course, I'm not a network guy and I haven't done extensive testing, so it's all hearsay. Finn On Wed, Apr 23, 2008 at 6:39 PM, Cary Millsap <cary.millsap@xxxxxxxxxxxx> wrote: > Jeff and I saw about a 55:1 response time improvement on a little PL/SQL > block that executed a few hundred thousand dbcalls in 2001 (this is the > first case study in the Optimizing Oracle Performance book). We ran once > connected to an alias with protocol=tcp, and then again using a different > alias with protocol=beq. Then we ran test 1 again, then test 2 again, to > eliminate the possibility that the performance improvement was just an > artifact of db block buffer caching. > > I don't have the repro case for the test we did, but it was something like > a select of one row from a real table executed over and over again. It > repeatedly ran about a minute through TCP and about a second through BEQ. > > Cary Millsap > > > > On Wed, Apr 23, 2008 at 3:50 PM, Jared Still <jkstill@xxxxxxxxx> wrote: > > > Env: > > > > Linux 2.6. on Intel > > Oracle 10.2.0.3 > > > > In the past I have been led to believe (without much proof) that when > > connecting > > to a database on the local server, that IPC should always be used to > > avoid the > > performance hit of going through the TCP stack. > > > > Using a modified version of Tom Kyte's run_stats that allows for > > collecting > > stats from two different sessions, some minimal testing seems to > > indicate > > there is little difference whether connecting via IPC or TCP. > > > > Of course you are probably asking: > > "If you are on the server, why setup either?" > > > > The answer is because many applications always connect through TNS. > > > > In any case, I don't see much difference regardless of how the > > connection is made > > while on the server. > > > > Has anyone here done any testing on this? > > > > Or perhaps it is something that changed in a release? > > > > Thanks, > > > > -- > > Jared Still > > Certifiable Oracle DBA and Part Time Perl Evangelist > > > >