Re: Wait event "SQL*Net more data to client" in wait class "Network"
- From: Charles Hooper <hooperc2000@xxxxxxxxx>
- Date: Fri, 23 Nov 2007 17:05:38 -0800 (PST)
On Nov 23, 1:30 pm, chris <cboi...@xxxxxx> wrote:
Hi,
Starting last week my application got problem "SQL*Net more data to
client"
1 connection on 10 hang for about 10 secondes.
I'd check the network, and everything is ok, and the problem is
randomly
yesterday afternoon, everything go fine, this morning it hang a lot
My env :
Oracle 10.2.0.3 std 64bit
Win 2003 ent 64bit
VB 6 app design "Just-in-time" connection
connect via microsoft ODBC
I have 4 websites connecting on the same instance, with no problem
and same design ...
The only difference between website and the vb6 app is the network
segment
website and Db are on the same network segment (DMZ) and the app is
in
the Intranet (Inside interface)
I'll monitor my FW to see if something wrong ... but change nothing on
this recently
If someone have seen this, maybe have a solution ...
Thank you
Chris
(sorry if my english is poor)
In addition to Sybrand's comments, you may want to investigate a
couple additional items:
* I am familar with VB6, but not the term '"Just-in-time"
connection'. Is the VB 6 application connecting and disconnecting
from the database server, or does it keep the same connection open?
Each new connection will likely create a new thread on the Windows
server, and the disconnection will likely terminate the thread - this
is probably less time consuming than the equivalent on Unix, where a
new process is created or destroyed, but should be avoided if
possible. The database server may cache a previously disconnected
session in the event that a new session will be created by the same
calling application, do that may reduce the time for the second and
following connection requests.
* The firewall between the client (on the LAN) and database (in the
DMZ) may be responsible for some/all of the delay. How is the
firewall configured to handle packets to/from the database server in
the DMZ? Is it a stateful firewall? What is the MTU setting on the
firewall?
* How does the application perform when using Oracle's ODBC client or
OLEDB (Provider=OraOLEDB.Oracle)?
I suggest that you run a packet capture utility, such as Wireshark, on
the client and server (I have not had a chance to test Wireshark on 64
bit Windows, so I am not sure if it will affect stability, but it runs
fine on 32 bit Windows). Wireshark will be able to indicate if
packets are being lost and retransmitted, and even if differences in
MTU (or other settings), Nagle/delayed ACKs or something else is
causing the delay at the network level. Reading a packet capture
takes a bit of practice.
Charles Hooper
IT Manager/Oracle DBA
K&M Machine-Fabricating, Inc.
.
- Follow-Ups:
- References:
- Prev by Date: Re: Wait event "SQL*Net more data to client" in wait class "Network"
- Next by Date: Re: UNION ALL and ordering
- Previous by thread: Re: Wait event "SQL*Net more data to client" in wait class "Network"
- Next by thread: Re: Wait event "SQL*Net more data to client" in wait class "Network"
- Index(es):
Relevant Pages
|
