Hi,

I just found out the number of context switches a process( browser) undergoes using the field task->nvcsw and its interesting to see the following numbers,

1277,1277,1535,4087,9981,9981,9981,9975,9973,10229, 10231,10231,10229,9561,9469,10229,11509,11775....

Could anybody guide me why there is a variation in the numbers. I was expecting a monotonically increasing sequence for the number of context switches.

The CPU scheduler in the OS kernel is responsible for switching tasks. It probably thinks other processes would like to use the CPU besides just your process, after having given it a bit more to see if it was temporary process (doing its job and exiting fast). It could also be for any number of reasons, all very hard to know because Linux has undergone a fairly dramatic CPU scheduler change, and while the CPU scheduler is always being fiddled with, its hard to really know what its doing without knowing the exact versions, patches applied, etc. So, the only way to really know, is to read the source code, or perhaps just the documentation relevant to the CPU scheduler.