对于业务的激活码需求做了一次关于mysql,mongodb的比对.mysql分为normal,key partition 数量分别是1亿和10亿数据,mysql采用直接访问PK键,partition key为PK,mysql table size 为90G,mongodb table size为157G。

[liuyang@yhdem ~]$ cat /proc/cpuinfo  |grep processor |wc -l
24

[liuyang@yhdem ~]$ cat /etc/issue
Oracle Linux Server release 5.8
Kerne[......]
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Nmap (“Network Mapper”) is an open source tool for network exploration and security auditing. It was designed to rapidly scan large networks, although it works fine against single hosts. While Nmap is commonly used for security audits, many systems and network administrators find it useful for routi[……]

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ASR XD报警抛出如下错误

"
dm01cel02: Hardware Error has been detected in the Flash Logs on the Cell Node
dm01cel02: Please open up a Service Request with Oracle to resolve the Error
dm01cel02: View File /tmp/ASR-Flash-Fault-Check-Log for further Information of the Error
dm01cel02: This log File c[......]
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基于上次的nicstat linux还提供了nethogs,可以监控指定pid的具体流量,在这里可以下到源码.

获取过程：

open("/proc/$pid/fd")
open("/proc/net/tcp")
open("/proc/net/tcp6")
open("/etc/passwd")

eg:

[root@db-81 27274]# nethogs  -d  5

NetHogs version 0.7.snapshot

  PID USER     PRO[......]
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oracle 11gR2 rac listener引入了3项主要的改变：

1. listener默认owner为grid

[oracle@db-42 ~]$ srvctl config listener
Name: LISTENER
Network: 1, Owner: grid
Home:
End points: TCP:1521

2. listener 被oracle agent 所管理 (oraagent)
[grid@db-41 admin]$ ps -ef |grep oraagent
grid 22195 18519 0 16:42 pts[……]

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[……]

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同事aaqwsh做的关于Exadata-X2-2的smart scan总结[……]

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我们可以通过v$sql_bind_capture 捕获到 bind values 这篇文章主要阐述v$sql_bind_capture与v$sql_plan的一些联系

SQL*Plus: Release 11.2.0.3.0 Production on Tue Aug 28 14:07:13 2012

Copyright (c) 1982, 2011, Oracle.  All rights reserved.

Connected to an idle instance.

SQL> startup
ORACLE instance started.[......]
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整理一篇关于11g smart flash cache 的文章,louisliu

我们来做一下演示 采用FusionIO SLC 160G

[oracle@db-41 ~]$ ls -l /dev/fioa 
brw-r----- 1 oracle oinstall 252, 0 Jul 17 14:26 /dev/fioa


[root@db-41 dev]# fio-status

Found 1 ioDrive in this system
Fusion-io dri[......]
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Oracle Exadata 从 11.2.2.4.0开始引入了 Smart Flash Logging的新特性，在exadata环境中,当oracle 需要写入日志的时候将会启动parallel write 同时在 disk 和 flash两端写入数据,controller中有任意一个率先写完就会通知RDBMS数据库继续工作， 该特性着力于提高Exadata对Redo写入的响应时间和吞吐量。(The feature allows redo writes to be written to both flash cache and disk controller cache, with an a[……]

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