Investigating linux server slow down

Question

We have a code build server, fedora 13, which was working at medium speed for 4 users. Speed means building a code branch took 1.5 hrs max duration. It was having one quad core, 8gb ram, 200gb hdd.

To increase the performance as well as the number of users to 8, its hw config is increased to 8 cores, 47gb ram, 2tb hdd. But now even when a single user is using the server it is very slow, it takes > 7hrs to build a code.

For increase in hw it is supposed to be faster. What can make it slow? If I reduce the swappiness 'll it help? Or a reinstallation of os isneeded?

Please help. New to linux server.

$ df -h  
Filesystem            Size  Used Avail Use% Mounted on
/dev/mapper/vg_pclin525-lv_root
                       50G   32G   16G  67% /
tmpfs                  24G  204K   24G   1% /dev/shm
/dev/sda1             485M   47M  414M  11% /boot
/dev/mapper/vg_pclin525-lv_home
                      213G   64G  138G  32% /usr2
/dev/sdb1             1.8T  158G  1.6T  10% /usr3


$ free -tg
              total       used       free     shared    buffers     cached
Mem:            47         43          3          0          3         35
-/+ buffers/cache:          4         42
Swap:            5          0          5
Total:          53         43          9

Answer 1

Fedora 13 was released on 2010-05-25 - more than 4 years ago. If you replaced hardware (motherboard, CPU, memory) without upgrading OS, most likely old kernel 2.6.33 cannot properly support new hardware - SATA chip, NIC, etc that are present in your new computer.

In other words, you should really install more recent version of Linux (Fedora 20 or Ubuntu 14.04) - it should improve things a lot.

If that does not help, I would recommend using utility atop (install with sudo yum install atop) to analyze what is slowing your server down during the build. It could be CPU, disk subsystem or something else - you will see it clearly.

BTW, if you were able to invest into new computer with 48GB RAM (which alone must cost you $2000+), why didn't you invest into better disk subsystem? These days, 1TB SSD can be purchased for less than $500.