Informix profiling / debugging - speed of sql statements ?
Guido Stepken
After my bad experiences with informix on linux (no KAIO, SMP not
runnning with 9.30) i tried to improve speed on a complex database
.
onstat -u shows all sessions and onstat -g sql SESSIONID shows all
SQL statements one user lets run - so says the manual.
In practice the command onstat -g sql SESSIONID crashes and Option -o
filexy writes about 50 mbyte/sec into this file. Strange - according to
the manual only sql statements should have been written. IDS 7.3 on HP
UX shows this a well as IDS 9.30 on Linux.
What am i missing ?
tnx and regards, Guido Stepken
David Williams
"Guido Stepken" <g.st...@t-online.de> wrote in message
news:beonn4$dtp$01$1...@news.t-online.com...
> Hi out there !
>
> After my bad experiences with informix on linux (no KAIO, SMP not
> runnning with 9.30) i tried to improve speed on a complex database
> .
> onstat -u shows all sessions and onstat -g sql SESSIONID shows all
> SQL statements one user lets run - so says the manual.
Nope, onstat -g sql sessionid shows the current query and the last prepared
one.
>
> In practice the command onstat -g sql SESSIONID crashes and Option -o
How does it crash?
> filexy writes about 50 mbyte/sec into this file. Strange - according to
-o dumps shared memory to a file whatever
onstat -
gives as the size of shared memory is what onstat will be writing to the
file. Fast
isn't it?
> the manual only sql statements should have been written. IDS 7.3 on HP
Nope -o is the dump shared memory option. What is the exact command you are
using?
Guido Stepken
or tail -f file|grep expression ...
worked for me to debug (and profile) informix.
tnx for having helped.
I have still several problems:
cannot access shared memory after having edited onconfig by hand with
joe or vi. I did a killall -HUP oninit afterwards and onstat -a shows,
that informix accepted the new settings without having to be restarted.
informix crashes suddenly after some time and refuses to restart with
this error. Configuring informix only with onmonitor worked for me.
Seems, there are 2 onconfig parsers working in oninit, one is more
tolerant as the other .... informix is running quite stable now.
DUAL XEON with informix 9.30 UC2 + or 9.40 on redhat 8.0 works,
switching to MultiProcessor lets informix die after a short time.
Informix Linux in fact only uses one processor.
So XEON is not the best choice - AMD Opteron seems to be the better
choice for informix.
regards, Guido Stepken