SSD causing 100% CPU usage in Apache/PHP

Posted by Tim Reynolds on Super User See other posts from Super User or by Tim Reynolds
Published on 2012-06-01T16:32:06Z Indexed on 2012/06/01 16:43 UTC
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I wanted to increase the performance on my development laptop so I added an Intel 320 Series SSD as my primary drive. Everything is amazingly fast, as expected, except Apache/PHP.

I develop Magento by using an Ubuntu 10.10 virtual machine.

Information: 
Host OS:  Win 7 Professional 64bit
Guest OS: Ubuntu 10.10 32bit
Processor: i7 
Chipset QM55 
SSD: Intel 320 Series 160gb 30% full
HDD: Hitachi 320gb 50% full (in side bay using an adapter)
Laptop: Lenovo T510
Using: Shared folders
Apache Version: 2.2.16
PHP Version: 5.3.3-1
APC Version: 3.1.3p1
APC Memory: 128M
Using tmpfs for cache, log, session directories in Magento

In the VM running on the SSD (VM files and source files are on the same drive) loading a product page in the Admin takes on average 26.2 seconds and uses 100% CPU for nearly the entire time.

In the VM running on the old HDD loading the same page takes on average 4.4 seconds. It mostly uses around 40-50% of the CPU while rendering the page.

I have read this post: Performance issues when using SSD for a developer notebook (WAMP/LAMP stack)?

It says to change some settings in the bios. I have turned any and all power management features off in the bios. I can't for the life of me understand why this would be happening.

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