IDS 11.7 Tuning help

[Laurie Gustin]

We have recently migrated from IDS 11.5 to IDS11.70 FC5 instance running on
Linux. We have one application that makes many separate connections to the
database. They connect, run small queries and disconnect. The queries
usually take less than one second, so these connections come and go very
quickly and there are alot of them.

We are experiencing some slowness on the 11.7 server that we did not see on
11.5, so I'm looking for help getting this new server tuned up. The only
think I know to look at is NETTYPE params

11.5 - NETTYPE soctcp, 50, 100, NET - when I start this engine I get this
error: Warning: Number of poll threads for nettype soctcp has already
reached the maximum of 50
11.7 - NETTYPE soctcp, 40, 100, NET

Thanks in advance!

Laurie

[John Miller iii]

Laurie:

I would suggest a few of the following. First utilize the new cache
capability this will reduce the number of network calls to the operating
system. Second, make sure FASTPOLLing is enabled. Ensure you have more
than one FD server to spread the load around.

NS_CACHE host=900,service=900,user=900,group=900
FASTPOLL 1
NUMFDSERVERS 4

In addition, I would look at using multiple listener threads for the same
port. This is done by simply adding
a (-count) to the end of the Informix server name in the onconfig. The
example below will start 3 listener threads
all servicing the port associated with the "blazer".



DBSERVERNAME blazer-3

Hope this helps,
John F. Miller III

Date: 01/09/2013 11:48 AM
Subject: IDS 11.7 Tuning help
We have recently migrated from IDS 11.5 to IDS11.70 FC5 instance
running on Linux.  We have one application that makes many separate
connections to the database.  They connect, run small queries and
disconnect.  The queries usually take less than one second, so these
connections come and go very quickly and there are alot of them.
We are experiencing some slowness on the 11.7 server that we did not
see on 11.5, so I'm looking for help getting this new server tuned
up.  The only think I know to look at is NETTYPE params
11.5 -  NETTYPE soctcp, 50, 100, NET  - when I start this engine I
get this error:  Warning: Number of poll threads for nettype soctcp
has already reached the maximum of 50
11.7 -  NETTYPE soctcp, 40, 100, NET
Thanks in advance!
Laurie_______________________________________________
Informix-list mailing list
http://www.iiug.org/mailman/listinfo/informix-list

[a***@gmail.com]

Hi whats is the advantage for using 3 threads on the database port, is it load blancing connexion ?

[Laurie Gustin]

Thanks John -
I do already have the cache set up..

NETTYPE soctcp,40,100,NET
LISTEN_TIMEOUT 60
MAX_INCOMPLETE_CONNECTIONS 1024
FASTPOLL 1
NUMFDSERVERS 4
NS_CACHE host=900,service=900,user=900,group=900

I will try increasing the number of listeners for the port...

Laurie

Post by John Miller iii
I would suggest a few of the following. First utilize the new cache
capability this will reduce the number of network calls to the operating
system. Second, make sure FASTPOLLing is enabled. Ensure you have more
than one FD server to spread the load around.
NS_CACHE host=900,service=900,user=900,group=900
FASTPOLL 1
NUMFDSERVERS 4
In addition, I would look at using multiple listener threads for the same
port. This is done by simply adding
a (-count) to the end of the Informix server name in the onconfig. The
example below will start 3 listener threads
all servicing the port associated with the "blazer".
DBSERVERNAME blazer-3
Hope this helps,
John F. Miller III

Date: 01/09/2013 11:48 AM
Subject: IDS 11.7 Tuning help
We have recently migrated from IDS 11.5 to IDS11.70 FC5 instance
running on Linux. We have one application that makes many separate
connections to the database. They connect, run small queries and
disconnect. The queries usually take less than one second, so these
connections come and go very quickly and there are alot of them.
We are experiencing some slowness on the 11.7 server that we did not
see on 11.5, so I'm looking for help getting this new server tuned
up. The only think I know to look at is NETTYPE params
11.5 - NETTYPE soctcp, 50, 100, NET - when I start this engine I
get this error: Warning: Number of poll threads for nettype soctcp
has already reached the maximum of 50
11.7 - NETTYPE soctcp, 40, 100, NET
Thanks in advance!
Laurie_______________________________________________
Informix-list mailing list
http://www.iiug.org/mailman/listinfo/informix-list

[Fernando Nunes]

I'm afraid I'm missing something... Can you better define the slowness? Do
the sub-second queries take longer now? Or do you believe it's the
connection establishment that takes longer?

Make sure you follow John's suggestions... A few more questions:

- Are you sure ther is no sysdbopen() procedure being run?
- How many connects per second do you have? (audit facility can tell you
this easily)
- Why do you have 40 poll threads?
- Do you already have NUMFDSERVERS?
- Do you see many sessions with flag "S" in onstat -u? If yes, do you see
nsf lock very "hot"? (onstat -g wmx or onstat -g lmx)
- How is your ready queue? (onstat -g rea -r 1)
- How is the load on the machine?
- If the load is too high, are the oninits causing it? And if yes, which
oninits? (CPUVPs or the poll threads?
- Can you check the quick queries query plan? Do they look ok?


Regards.

Post by Laurie Gustin
We have recently migrated from IDS 11.5 to IDS11.70 FC5 instance running
on Linux. We have one application that makes many separate connections to
the database. They connect, run small queries and disconnect. The queries
usually take less than one second, so these connections come and go very
quickly and there are alot of them.
We are experiencing some slowness on the 11.7 server that we did not see
on 11.5, so I'm looking for help getting this new server tuned up. The
only think I know to look at is NETTYPE params
11.5 - NETTYPE soctcp, 50, 100, NET - when I start this engine I get
this error: Warning: Number of poll threads for nettype soctcp has already
reached the maximum of 50
11.7 - NETTYPE soctcp, 40, 100, NET
Thanks in advance!
Laurie
_______________________________________________
Informix-list mailing list
http://www.iiug.org/mailman/listinfo/informix-list