VMware guest optimization: Linux

In an effort to squeeze every bit of performance and achieve maximum efficiency out of our vSphere farm, I came across adjusting "ticks" in recent kernel releases. As far as I understand it, ticks are the method in which the CPU(s) query the kernel activity. The more the ticking, the more the checking. Ticks can be favorable for desktop installations such as a user moving the mouse while compiling a program. Compiling is processor intensive but because of the ticks, the CPU looks for the mouse movement in order to fluidly paint the movement across the screen.

Most server installations don't use a mouse often. Therefore, the treadoff may be less variable but the kernel is able to process jobs longer. A side effect, among many, is less power consumption because the kernel isn't constantly nagging the processor(s). It is recommended that Linux VMs employ some sort of tick managment to reduce the activity. Here is a link from VMware showing the various distros that support tick management and how to enable it.

I changed a test CentOS VM and the results were interesting. Check out the idle CPU prior to reboot(spiked activity) and after. Changing this in 1 - 2 VMs, may not yield much for results. However, across 15-30 per host, as we consistently run on our hosts in the farm, we can gain back some needed processing powa!

Gotta Have IT

It has occurred to me that there are 3 vital game changers out there.
Data deduplication
Virtualization
Wan optimization

All encompass maximizing efficiency.
Data dedupe gives you back 30 to 40 percent of your storage by finding
indentical blocks of data and placing pointers to it rather than writing
full copies of data. So,with file level dedupe, you have 1 copy of
a word document with 5 pointers referncing it rather than 6 full
copies.With block level dedupe, you save 1 version of the text
"thank you"; from every file with additional pointers, rather
than 8 billion strings of that text. It ain't cheap but pays for
itself.

Virtualization.The newest in sliced bread. Remember
mainframes? The more things change, the more they stay the
same Jam a bunch of separate, functional apps in one place
gaining resource, hardware, and operational efficiencies. With an
avg server running at 5% efficiency, this is very wasteful of the
aforementioned resources. The savings can be astronomical
depending on environment.

Wan optimization. This merges many technology concepts to provide
reduced latency and response times across slow links through caching,
compression and other secret sauce. Response times are akin to being on
a LAN.

Coolness comes at cost though. However, long run, all will save
you $.