Saturday Apr 03, 2010

Random Notes - DB and JDBC work

Doing DB tasks after a while gave me a feeling that I am learning few things again..
happens.. ! I guess.
Just to make sure it doesn't happen again,

Random Notes

- I was able to use the Hibernate Toolkit for creating Callable Statement.
- Passing String array is okay, make sure to implement the annonymus class Array
- Don't use commas as separators within an array element
Postgres treats commas as field separators
- Debugging is a challenge, if you have insert statements within, you cannot use commit. Have the inserts inside begin .. end; and from java client, beginTransaction and then commit. The log lines will not appear without commit.
- For substring, use substr (, );
- If you have create temp table, use create temp table without oid and EXECUTE
that statement.
For any inserts or other transactions on the temp table, use EXECUTE again.
Otherwise java client or any client will error out saying table with OID not

Friday Dec 14, 2007

Solaris Containers came to the rescue

One of my friends leading a quality team responsible for performance/stress testing of a network intensive application, had something interesting to discuss with me few months back.
The application has multiple instances of a component communicating to a central server over the network. In a customer environment, this piece of the software has one instance on one OS instance. This one does a lot of snmp talk back n forth with the server. The test case was to have ~1500 instances talking to a single server at a time. His team has a simulation script that runs 50 to 100 instances on one box. He had used 15 to 30 Solaris 8 and 9 hosts some 4 yrs back to successfully test it. Amazing effort ! Because those many instances are good enough to drive the system crazy. And managing 15 to 30 such system must have been SOMEthing!
The current situation was that he had a lab with reduced resources, a smaller team and very few days to repeat it with the latest version of the same s/w. So I gave him the obvious suggestion ! Virtualize the host(s) to get the magic set of 15 to 30 os instances. And more obvious choice of virtualization technology in this case, Solaris Containers. All the team needed was multiple OS instances of the same OS flair. Within this constraint, containers are extremely lightweight. The team had a 24 vCPU 48 G RAM box that was selected to host them.
So it all looked great on the paper. One of his team members configured some 8 zones to start with and started instantiating 100 per zone. The moment the instances in just 2 of them started talking over the network, the system refused to respond to any of the terminals connected. Although there were s/w partitions in the form of zones, all were sharing a NIC.
A team meeting with a few glum faces and few 'I knew it' remarks... And here is when the exclusive IP stack support added to containers came to the rescue !!! With additional NICs on board, and an upgrade to Solaris 10 Update 4, the zones were reconfigured to have exclusive ip type. And it worked !! 30 boxes down to a single box. So easy to manage, fast boot and shutdown, nearly instantaneous replication with cloning to get 16 Containers running 100 instances each. Cool Stuff !!!

Wednesday Nov 14, 2007

Sun Management Center 4.0 is out

Now that Sun Management Center 4.0 has been released, I guess I can come back to blogging a bit.

SunMC 4.0

A lot of resources are available in the form of blogs, documents, forums, web casts. Some of them are:

  1. SunMC 4.0 in action managing Containers on the UltraSparc 2 Systems
  2. The product page
  3. Steve's blog
  4. The Sun Connection Blog
  5. The Big Admin Wiki

Let me try posting some feature specific information in my next posts.

Saturday Apr 21, 2007

What's new in container manager

We added a lot of cool features to Container Manager recently by means of 125830-03, 125831-03, 125832-03, 125833-03, 125834-03.

[Read More]

Saturday Dec 09, 2006


I was in mumbai yesterday and day before, talking about the most loved and hated term these days, 'virtualization' ...
[Read More]

Thursday Sep 07, 2006

Sun Fire T1000 Physical View

The lean and thin system looks like a helpless, small, dull box... What's that ! 24 Processors ??? !!! I can see only one, where are the remaining 23 of them !!!

[Read More]

Tuesday Jun 27, 2006

Extending Sun Management Center Agent Update

Agent Update can be exploited to deploy things like your own sunmc module, a bunch of files or a small application remotely on solaris sparc/i386, Linux, provided they are running sunmc 3.6 agents.[Read More]

Monday Jun 19, 2006

Hands free sun management center server installation

An installation configuration file for a hands free sunmc server installation.[Read More]

Friday Apr 14, 2006

They say container manager is ...

Had a conference call with folks outside sun who were not so impressed with what they saw of Solaris Container Manager.[Read More]



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