`
standalone
  • 浏览: 612997 次
  • 性别: Icon_minigender_1
  • 来自: 上海
社区版块
存档分类
最新评论
文章列表
量了一下4个datanode时候HDFS写操作时每个node分配block的情况,每个datanode是4张disk,写了个脚本处理log后发现平均每个node分配的block数量占写的
A post about KFS vs. HDFS October 02, 2007 Advantages of Kosmix's KFS vs. HDFS I was excited to learn last week that my friends at Kosmix have decided to open source a project long in the works: the Kosmix Distributed File System, or KFS  (see the offical blog post).  A number of people have comme ...

ZFS Features Summary

I summarize these from Wikipedia and other documents on ZFS . But some concepts still appear unclear to me, e.g, RAID-Z.   Pool Storage ZFS is not limited to devices and does not need volume manager any more.  File systems can share a common storage pool. creating filesystems i ...
I encounter exception below when I use copyFromLocal to copy several big files (10G) to HDFS. Hadoop guy’s word to explain this:  “I noticed the same recently. For me it happened since the datanodes were deleting lot of blocks. I was doing something like : bin/hadoop fs -rm 4Gb; sleep 10; bin/hadoop ...
I need to execute commands on several remote servers at the same time via ssh. Writing shell script to send commands to servers with code below is quite simple but has trouble to know when all the tasks are finished on all servers.             ssh $ip “nohup sh go.sh > log 2>&1 &am ...
mpstat –p ALL   And with time interval:   mpstat –p ALL 3  
I met this problem when I testing the open file operation latency of HDFS. In the stress test, I continuously open and close files for about 1000 seconds. See the resolution below. I get it from http://wiki.apache.org/hadoop/Hbase/Troubleshooting#6 Problem: "No live nodes contain curren ...
I met this problem last week and it frustrated me for days...Now I found the solution after I spent hours on google, and amazing it works!!! Linux NFS mount: failed, reason given by server: Permission denied This issue drove me nuts today for several hours today, to be honest I was pretty close t ...
看一个很重要的宏: CPPUNIT_TEST_SUITE_NAMED_REGISTRATION( MyTest, "alltest" ); 我也不清楚,先看宏定义吧,在HelpMacros.h里面: /** Adds the specified fixture suite to the specified registry suite. * \ingroup CreatingTestSuite * * This macro declares a static variable whose construction * causes a test s ...
目前网上搜索到的讲CppUnit源码解读基本来源于晨光CppUnit源码解读,是很好的源码阅读笔记。但是针对的是 CppUnit1.8.0版,现在网上下载到的一般都比这个新了,我下载的是1.12.1版,代码有一些变动,就结合晨光的 笔记仔细看了一些源码。 首先看一下我们通常写的简单的测试类:   class MyTest : public CppUnit::TestFixture { CPPUNIT_TEST_SUITE( MyTest ); CPPUNIT_TEST( testEqual ); CPPUNIT_TEST_SUITE_END(); public: v ...
#include <iostream> #include <iomanip> #pragma comment (lib, "psapi.lib") // Add 'psapi.lib' to your linker options #include <windows.h> #include <psapi.h> using namespace std; int main() { // Open current process HANDLE hProcess = ::OpenProcess ...
Global site tag (gtag.js) - Google Analytics