Comment 36 for bug 879334

dilan (dilanasanga-x) wrote :

Hi All,

I have also setup the same environment at my office for developers to work with JAVA and PHP etc., which was very slow initially.

Later I came to know programs like Netbeans, firefox, Chrome and systems logged in users cache is created in users home (as hidden directories) itself and when there are lot of users logged into system, huge amount of disk I/O goes due to the data operations. Because all users are writing to their homes which is in the same disk (I have setup raid 1 there)

What I simply did was moved all those caching directories to users local hard disk and created symbolic links to them. This gave a significant performance improvement.

like this
root@rcapladm:/home/dilan# pwd

root@rcapladm:/home/dilan# ls -la

lrwxrwxrwx 1 dilan users 25 May 5 09:55 .local -> /rcapl/home/dilan/.local
lrwxrwxrwx 1 dilan users 27 May 5 09:55 .mozilla -> /rcapl/home/dilan/.mozilla
lrwxrwxrwx 1 dilan users 25 Aug 18 08:37 .mysql -> /rcapl/home/dilan/.mysql
lrwxrwxrwx 1 dilan users 29 Aug 18 08:38 .mysqlgui -> /rcapl/home/dilan/.mysqlgui/
lrwxrwxrwx 1 dilan users 28 May 5 09:55 .netbeans -> /rcapl/home/dilan/.netbeans
lrwxrwxrwx 1 dilan users 34 May 5 09:55 .netbeans-derby -> /rcapl/home/dilan/.netbeans-derby

Because now their caching (which uses most of disk IO ) is now not at server, and it is in local machine server does not have lots of disk IO. Still when a java application compiles using "mvn clean compile", compilation was slow. I also applied a simple trick in their pom.xml to set the compilation location not in the server but in the local machine. Then that was also fast. So all their source codes are in server, protected.

I don't say system is 100 perfect at all. Still little slowness is there.

Still my biggest problem is, if any users network is gone, suddenly the nfs mount goes off and system gets stuck with increasing load. I cannot see any program using system load when I check with "top" command , but system gets stuck and even network comes back, it is not re mounting the users home automatically 90 times out of 100. Even we cannot do it manually. Because when I type "df -h", it shows nothing but trying to get mount information.

Any Idea or solution. ?

Thanks all.

Specks of my NFS & LDAP server.

Cor2Duo Intel, 4 GB RAM, 500 HD (Normal) with RAID 1.
Around 10 Users working this Environment.