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Some data collection display

Posted by admin on August 21st, 2014

Reference Oracle AWR. These two was developed by python and perl.

Both of these are following data collection method.

Use these tools can help quick identify problem.

MyAWR v2 –collection of mysql and os information

MongoAWR v1 — collection of mongodb and os information

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Posted in MYSQL, NoSQL | No Comments »

Talk about some MySQL HA architecture

Posted by admin on August 12th, 2014

Some tips for MySQL architecture

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Advance for MySQL Pagination

Posted by admin on July 28th, 2014

看到叶金荣的一篇关于mysql分页的文章,结合雅虎之前发的一篇PDF 谈谈自己的看法

在叶子的文章里谈到了使用inner join 从而减少了对page的扫描也就是减少了所谓的回表 例如:

SELECT * FROM `t1` INNER JOIN ( SELECT id FROM `t1`ORDER BY id DESC LIMIT 935500,10) t2 USING (id)

通过直接对id的操作 而不是整张表的扫描 通过id 的join 抓出符合条件id 然后通过ID 再去做数据的抓取。这样就避免了对不需要的页面的扫描。

不过这样也不是最佳的方法 还可以通过对[......]

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小型机迁移x86平台之老生常谈

Posted by admin on July 17th, 2014

You can view this presentation click here: x86_architect
注意使用chrome打开文件 不然可能乱码

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Posted in Oracle Experience, Unix/Linux | No Comments »

NoSQL压测工具YCSB

Posted by admin on July 16th, 2014

Download PDF from slideshare

基于mongodb的压力评测工具 YCSB的一些概括

YCSB 是一款基于NOSQL Benchmark的工具,提供了多种方式模拟测试nosql的负载,基于现在对nosql的一些压力测试还没有得到重视.
YCSB 的全面的测试功能可以给即将上线的nosql提供一种另类保障。

There are many new serving databases available, including:

PNUTS
BigTable
HBase
Hypertable
Azure
Cassandra
Couch[......]

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MongoDB not preallocate journal log

Posted by admin on June 19th, 2014

在安装mongodb 2.6.2的时候发现一个奇怪的问题 RS 节点的journal log并没有提前分配.我们知道在安装mongodb的时候
mongo总是会预先分配journal log 启用smallfile的时候默认为128MB 否则会分配1GB的journal log

下面是仲裁节点的日志:

2014-06-17T11:50:09.842+0800 [initandlisten] MongoDB starting : pid=4749 port=27017 dbpath=/data/mongodb/data 64-bit host=vm-3-57
2014-06-[......]

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MySQL Fabric HA&Sharding solutions

Posted by admin on June 18th, 2014

MySQL Fabric

Download : MySQL fabric solutions

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Good news for MySQL HA solutions

Posted by admin on June 9th, 2014


Oracle Clusterware is portable cluster software that allows clustering of independent servers so that they cooperate as a single system. Oracle Clusterware was first released with Oracle Database 10g Release 1 as the required cluster technology for the Oracle multi-instance database,  Oracle[......]

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news in mysqlbinlog – Back Up Master Binary Log Files

Posted by admin on May 13th, 2014

news in mysqlbinlog – Back Up Master Binary Log Files

从mysql5.6开始 mysqlbinlog开始支持远程读取master主机的binlog写入本地,极大的加强了binlog的备份策略,由于在mysql cluster复制环境中,binlog的存在极大的决定的数据恢复的完整性,所以binlog的备份显得特别重要。在诸多HA方案中,例如MHA,使用主库的binlog去恢复主备库之间的数据差,在主库物理机器down机无法重启的情况下,binlog的备份可以直接用来recover slave.所以这一特性提升mysql 容灾级别,使[......]

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Multi-Master-Rep in MySQL DB

Posted by admin on May 12th, 2014

Multi-master-rep

two masters:

-- 192.168.126.128 mysql 5.6.12
-- 192.168.126.129 mysql 5.6.12
slave :

-- 192.168.126.130 MariaDB 10.0
from one master machine create new db and insert one record:

23:44:55 (none)> show master status
    -> ;
+------------------+-------[......]

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