Dropbox - cloud storage 用途

該想一下如何利用這xxTB的空間
1. File Server安裝dropbox，就不用做備份了，因為會直接同步到雲端，缺點是還原後windows ACL會跑掉。
2. 之前放在硬碟裡面的軟體installation files，好幾TB，就直接丟到dropbox去了，需要用的時候再開啟該目錄的同步。
3. 用來做跨國際的DR initial sync檔案傳送。

Virtualisation - Intel based CPU / ARM based CPU

在 Intel or ARM based computer 上面安裝hypervison，然後在其上安裝linux的source是否相同 ?
--> 如果是simulator, 使用linux 安裝光碟
--> 但是virtualization is not emulation, it work like a software partitioning of the existing resources，所以是用不同的光碟
--> 雖然intel based or ARM based 都是執行linux，但是其上的opensource application要重新編譯過，才能切換不同的平台使用

Oracle DB- Using the Oracle KEEP pool (Caching)

Oracle Automating Script for KEEP Pool Caching Tables & Indexes db_keep_cache_size
http://www.dba-oracle.com/t_script_automate_keep_pool_tables_indexes.htm

Using the Oracle KEEP pool
http://www.dba-oracle.com/oracle_tips_cache_small_fts.htm

Using the KEEP and RECYCLE Pool
http://www.toadworld.com/platforms/oracle/w/wiki/1347.using-the-keep-and-recycle-pool.aspx


Sometimes, data blocks are read in the database, and are infrequently reused. Often in a database we also have data blocks that are of frequent use (hot blocks). It is for these types of database blocks (and the objects associated with them) that Oracle offers the keep and recycle buffer pools. In this topic we will quickly review the database buffer cache, what the keep and recycle pools are, how to determine which objects to put in the keep pool, how to enable the buffer pool features, and finally how to assign objects to the buffer pools.

Buffer Cache Overview
Introducing the Keep and Recycle Pools
Analyze the Buffer Cache Usage
Enabling Multiple Buffer Pools
Dynamic Memory Allocation in Oracle9i
Guidelines for Initialization Parameters For Oracle8i
Allocating Segments to Different Pools

--Dell to Acquire Quest Software

Linux - Shell scripting, Show command executed along with output in log file

1. 用echo or printf

2. 用set -x


[root@testdb4 script]# tar cf /tmp/test.tar -T /root/script/tar_from.txt
tar: Removing leading `/' from member names
[root@testdb4 script]#
[root@testdb4 script]# /root/script/test_tar2.sh
[root@testdb4 script]#
[root@testdb4 script]# cat test_tar2.sh.out
+ tar cf /tmp/test.tar -T /root/script/tar_from.txt
tar: Removing leading `/' from member names
[root@testdb4 script]#
[root@testdb4 script]# cat /root/script/test_tar2.sh
#!/bin/sh
out=$0.out
set -x
{
tar cf /tmp/test.tar -T /root/script/tar_from.txt
} >$out 2>&1



[root@testdb4 script]# cat /root/script/test_tar2.sh
#!/bin/sh
out=$0.out
#set -x
{
tar cf /tmp/test.tar -T /root/script/tar_from.txt
} >$out 2>&1
[root@testdb4 script]# /root/script/test_tar2.sh
[root@testdb4 script]# cat test_tar2.sh.out
tar: Removing leading `/' from member names

• 2>&1 indicates that the standard error (2>) is redirected to the same file descriptor that is pointed by standard output (&1).