Re: LOB Operation and SQL*Net Message From Client and cursor #0

From: Sriram Kumar <k.sriramkumar_at_gmail.com>
Date: Tue, 30 Apr 2013 20:31:24 +0530
Message-ID: <CAEq4C0fGaHn=AbEV9NcwQCQFbU4qT5-pbTuTbx6kbQuUfotaTw_at_mail.gmail.com>

Hi,
Whats the typical size of the LOBs and what is the client tier (Java?). have you used wireshark or a sniffing tool to see how the typical LOB segment is shipped to DB server?

Best Regards

Sriram

On Tue, Apr 30, 2013 at 6:52 AM, Larry Elkins <elkinsl_at_verizon.net> wrote:

> 10.2.0.5 EE on AIX 6.1
>
> Any known instrumentation issues / oddities when fetching LOBS?
>
> Tracing a process, 10046 level 8, 91% of the time on sql*net message from
> client, with 99.8% of that accumulated under cursor #0.
> Retraced with event 10051 turned on, indicated they were OPI call type 96,
> Lob/FILE operations.
>
> So, simple enough, a little over a million calls back on forth on those
> OPI level calls to get the LOB data. Precious little DB
> activity.
>
> But, techs with opnet installed and gathering data in different tiers
> swear there is little time on the network between the app
> server and the unix host where the database resides, that the time is *in*
> the DB. He's measuring nic to nic and acknowledgments
> between the app server and db server host, at least that's the way he
> described it. DB host is a VM.
>
> So first step is to make sure there isn't some sort of instrumentation bug
> in Oracle related to LOBS, and that the time I'm showing
> on sql*net message from client is indeed just that, and not something like
> "uncounted" CPU. And if it is indeed sql*net message from
> client, then we can start to look at where that time he shows is "in the
> database" actually is on that host.
>
> Larry G. Elkins
> elkinsl_at_verizon.net
>
>
>
> --
> http://www.freelists.org/webpage/oracle-l
>
>
>

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Received on Tue Apr 30 2013 - 17:01:24 CEST