Russel Brand on Mrs Thatcher

It has been a good year for Russell Brand, his wild child, devil may care image has been challenge for me after his confrontation with Paxman.

However it was today, reading an article for the Guardian reviewing top articles from 2013, that his piece on Mrs Thatcher really caught my eye:

http://www.theguardian.com/politics/2013/apr/09/russell-brand-margaret-thatcher

While looking back on events it easier to understand and to judge, but the record of the British Political elite in the 1980s still look very patchy.

I understand that their primary concern is drive forward British strategic and business interests, however it seems short sighted to me and history may judge them harshly.

I made a few notes and added them to my every expanding mind-map project:

Oracle on Linux - hugepage conciderations

Memory « Oracle Scratchpad This is an interesting article about the significant per process memory overhead of running Oracle on Linux without hugepages:

Upgrade to a 64-bit operating system and a 3GB SGA and you need 8 bytes for each page in the memory map and have 786,432 pages, for a total of 6MB per process.

The principles are explained very clearly in this article, but the key thing is that this overhead can build up quickly:

They should be using ”huge pages” (a.k.a large pages) for memory mapping. I can’t remember whether their platform supported 1MB or 2MB pages, but even at 1MB per page that would be 3,072 pages which means 24KB per process, for a total of 7.9 MB – reclaiming most of 2GB, which could go straight into the SGA, targeted at the buffer cache.

Subnet Masks and Subnetting

I haven't work very much previously with network configuration but I am looking at more and more RAC issues recently.

I have started reading up to: Pro Oracle Database 10g RAC on Linux

This is a very good book, I have seen Julian present at an Oracle SIG before, and was rather baffled by the advanced RAC issues he tackled (I was a newbie DBA at the time). Still he had lots of enthusiasm and I have since read a number of presentation online.

Anyway while reading up about I decided I needed a refresher on the background network concepts:

The "Subnet Masks and Subnetting" webpage gives a simple example of how to use a 255.255.255.128 subnet mask to a create a restricted part in a class C network (e.g. 192.168.1.0) for a small enterprise.

Next I moved on to a more detailed explanation on wikipedia, subnetwork masks:

This logical addressing structure permits the selective routing of IP packets across multiple networks via special gateway computers, called routers, to a destination host if the network prefixes of origination and destination hosts differ, or sent directly to a target host on the local network if they are the same. Routers constitute logical or physical borders between the subnets, and manage traffic between them. Each subnet is served by a designated default router... The routing prefix of an address is written in a form identical to that of the address itself. This is called the network mask, or netmask, of the address. For example, a specification of the most-significant 18 bits of an IPv4 address, 11111111.11111111.11000000.00000000, is written as 255.255.192.0.

another important background concept for CIDR notation :

192.168.0.0, netmask 255.255.0.0 is written as 192.168.0.0/16

192.168.1.0, netmask 255.255.255.0 is written as 192.168.1.0/24

this concept is clearest by looking at the full binary format:

Binary form Dot-decimal notation

IP address 11000000.10101000.00000101.10000010 192.168.5.130

Subnet mask 11111111.11111111.11111111.00000000 255.255.255.0

Network prefix 11000000.10101000.00000101.00000000 192.168.5.0

Host part 00000000.00000000.00000000.10000010 0.0.0.130

so going back to the first example, which has a restricted access server on the 2nd half of there private class C network with IP 192.168.1.131, netmask 255.255.255.128 is written as 192.168.1.3/25

Binary form Dot-decimal notation

IP address 11000000.10101000.00000001.10000011 192.168.1.3

Subnet mask 11111111.11111111.11111111.10000000 255.255.255.128

Network prefix 11000000.10101000.00000101.10000000 192.168.1.1

Host part 00000000.00000000.00000000.00000011 0.0.0.3

Perl and Oracle

This page (http://www.orafaq.com/wiki/Perl) shows all the basics of setting up a perl script connection to an Oracle database can making basic calls...

PHP Oracle FAQ - Oracle Wiki

PHP Oracle FAQ - Oracle Wiki

A very good page showing how to work with PHP and Oracle.

I stumbled onto this page as I was just looking for a sample/simple stored procedure to borrow:

create procedure proc1(p1 IN number, p2 OUT number) as

begin

p2 := p1 + 10;

end;

|MG| Win7codecs 2.6.9 Download

|MG| Win7codecs 2.6.9 Download

There is something mysterious about codecs ... this one comes highly recommended :)

ORACLE-BASE - Recompiling Invalid Schema Objects

ORACLE-BASE - Recompiling Invalid Schema Objects

this is a good background summary page... the commands I like to keep at my fingertips are:

spool pre-compile-errors.lst

col owner form a15

col object_name a60

set line 100

select OWNER, object_name, object_type, status from dba_objects where status <> 'VALID';

spool utlrp.lst

@?/rdbms/admin/utlrp

spool post-compile-errors.lst

col owner form a15

col object_name form a30

set line 100

select OWNER, object_name, object_type, status from dba_objects where status <> 'VALID';