SQL CONNECT
John Shepherd asked for typical times for the SQL CONNECT statement. David Williams said usually under a few seconds, even remotely. Rudy Fernandes tested Solaris machines on a 100 Mbit network and measured about 0.14 s real and 0.018 s CPU per connect/disconnect. Art Kagel said it depends on platform, connection type, network and load, citing sub-second to several seconds on his systems.
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Greetings, I have been asked to provide some estimates for "connect" times to databases. Does anyone have any average times for completion of an execution of the Informix SQL CONNECT statement ? I realise that this will be one of these "It Depends ..." type situations, but I would be grateful for some answers based upon experience. Many thanks indeed. Regards, John
In article <383706D3.D184B438@iname.com>, John Shepherd <johnshepherd@iname.com> writes >Greetings, >I have been asked to provide some estimates for "connect" times to >databases. >Does anyone have any average times for completion of an execution of the >Informix SQL CONNECT statement ? >I realise that this will be one of these "It Depends ..." type >situations, but I would be grateful for some answers based upon >experience. Many thanks indeed. >Regards, > John > Typically < a few seconds even to remote machines. Of course this is for 1 user and..it depends! -- David Williams
John Shepherd wrote:
> Greetings,
> I have been asked to provide some estimates for "connect" times to
> databases.
> Does anyone have any average times for completion of an execution of the
> Informix SQL CONNECT statement ?
> I realise that this will be one of these "It Depends ..." type
> situations, but I would be grateful for some answers based upon
> experience. Many thanks indeed.
> Regards,
> John
I had done a slightly 'formal' test of this under the following environment
Client Application : Shell script, running on Sun E450 : 2.6
Informix Server : running on a different Sun E450 : 2.6
Connectivity : 100 Mbit/sec network
Other Activity : None
The actual test involved 2 scenarios
Scene 1 : Connect, run simple sql, disconnect. Do this 200 times.
Scene 2 : Connect, run same sql 200 times, disconnect.
"time" and "onstat -p" results were compared (3 runs each).
Conclusions :
A single operation of connect/disconnect has the following costs
1. Real time : 0.14 secs
2. CPU time : 0.018 secs
HTH
Rudy
In article <383706D3.D184B438@iname.com>, John Shepherd <johnshepherd@iname.com> wrote: > Greetings, > I have been asked to provide some estimates for "connect" times to > databases. > Does anyone have any average times for completion of an execution of the > Informix SQL CONNECT statement ? > I realise that this will be one of these "It Depends ..." type > situations, but I would be grateful for some answers based upon > experience. Many thanks indeed. You are right, really big depends, on a lot of variables. Depends on: Server platform, client platform, connnection type (shared memory, stream pipe, network), speed of network if networked connections, load on the server (or even the client). For example connections on my production Data General Intel platforms are sub-second for shared memory, ethernet or fddi, on our production Sun platforms connections are even faster, on our production Data General Motorola M88k systems even shared memory connections can take up to 1.5 secs, on our development Data General Intel systems connections can take several seconds (even with 24 Pentium Pro processors several hundred programmers and 800MB ln sessions can bog down the system). Art S. Kagel Sent via Deja.com http://www.deja.com/ Before you buy.