Australia photo & PC memo

Send Email via Telnet

Telnet to hostname on port 25
HELO your_domain_name or whatever
MAIL FROM:you@hostname.com (ie, your email address)
RCPT TO:them@someplace_else.com (email address you want to send to)
DATA
You type your message then CRLF period CRLF (ie, type a period on a line by itself then hit ENTER)
QUIT

sqlplus:
set linesize 160
set pagesize 10000
set numformat 99999999999999999999999
alter session set NLS_DATE_FORMAT = 'YYYY-MM-DD HH24:MI:SS';
set serveroutput on

Performance check:
V$SESSION_WAIT
V$SYSTEM_EVENT

%u30C7%u30FC%u30BF%u30D9%u30FC%u30B9%u3092%u7279%u5B9A%u3059%u308B%u540D%u524D - %u30AA%u30E9%u30AF%u30EB%u30FBOracle%u3092%u30DE%u30B9%u30BF%u30FC%u3059%u308B%u305F%u3081%u306E%u57FA%u672C%u3068%u4ED5%u7D44%u307F

DBID (Database Identifer)
SELECT DBID,NAME,DB_UNIQUE_NAME,CURRENT_SCN,LOG_MODE FROM V$DATABASE;

SID (System Identifer)
Used in the host server to access shared memory.
Set in environment variables

INSTANCE_NAME
Used from outside of the host.
show parameter instance_name

DB_NAME
show parameter db_name

GLOBAL_NAME
Used to create DATABASE LINK

SERVICE_NAME
Used by LISTENER / TNSNAMES
show parameter service_name

Java%u30E1%u30E2%u30EA%u3001GC%u30C1%u30E5%u30FC%u30CB%u30F3%u30B0%u3068%u305D%u308C%u306B%u307E%u3064%u308F%u308B%u30C8%u30E9%u30D6%u30EB%u5BFE%u5FDC%u624B%u9806%u307E%u3068%u3081 - %u65E5%u8A18%u306E%u3088%u3046%u306A%u4F55%u304B

-verbose:gc(-Xloggc:path_to_file) GCログ出力を有効化
-XX:+PrintGCTimeStamps GCログにタイムスタンプ(Java起動時からの経過時間)を出力
-XX:+PrintGCDetails GCログを詳細に出力(New領域とJavaヒープそれぞれがどれだけ減ったか出力される)
-XX:+PrintClassHistogram*1 SIGQUITシグナル受信時にヒープ統計情報を出力(出力時に強制的にFull GCが発生)。-verbose:gc(-Xloggc:path_to_file)と併用必須。なお、SIGQUITシグナルを送信するには、kill -3 を実行すればよい
-XX:+HeapDumpOnOutOfMemoryError OutOfMemoryError発生時にヒープダンプを出力(Sun Java 1.4.2_12以上、1.5.0_07以上、1.6以上)

JVM Tuning

-Xms initial java heap size
-Xmx maximum java heap size
-Xmn the size of the heap for the young generation

Downloadinfos

%u3010%u30CF%u30A6%u30C4%u30FC%u3011JVM%u30EC%u30D9%u30EB%u3067%u30AF%u30E9%u30B9%u30BF%u30EA%u30F3%u30B0%u3092%u53EF%u80FD%u306B - Open Terracotta (1) JVM%u30EC%u30D9%u30EB%u306E%u30AF%u30E9%u30B9%u30BF%u30EA%u30F3%u30B0%u3063%u3066%u4F55? | %u30A8%u30F3%u30BF%u30FC%u30D7%u30E9%u30A4%u30BA | %u30DE%u30A4%u30B3%u30DF%u30B8%u30E3%u30FC%u30CA%u30EB