In the year 2010, the LHC machine has delivered 47pb−1 of
data to the CMS and the ATLAS detector, starting from the instantaneous
luminosity 1027cm−2s−1 to 2 × 1032cm−2s−1. Different
subdetectors of the CMS experiment were calibrated using
testbeam and some of them were calibrated again using cosmic
ray muons in the year 2008 and 2009. Here I will talk about the
performance of all those subdetectors in pp collision environment,
performances in early stage of low luminosity, how it changes with
higher luminosity and how are we preparing to cope with even
higher instantaneous luminosity, 1033 - 1034cm−2s−1. At the end,
I will talk about few important physics results from the CMS experiment.
