Context : The black hole candidate GX 339-4 exhibited an X-ray outburst in January 2010 , which is still continuing .
We here discuss the timing and the spectral properties of the outburst using RXTE data .

Aims : Our goal is to study the timing and spectral properties of GX 339-4 using its recent outburst data and extract information about the nature of the accretion flow .

Methods : We use RXTE archival data of the recent GX 339-4 outburst and analyze them with the NASA HEAsoft package , version 6.8 .
We then compare the observed quasi-periodic oscillation ( QPO ) frequencies with those from existing shock oscillation model and obtain the nature of evolution of the shock locations during the outburst .

Results : We found that the QPO frequencies are monotonically increasing from 0.102 Hz to 5.69 Hz within a period of \sim 26 days .
We explain this evolution with the propagating oscillatory shock ( POS ) solution and find the variation of the initial and final shock locations and strengths .
The model fits also give the velocity of the propagating shock wave , which is responsible for the generation of QPOs and their evolutions , at \sim 10 m s ^ { -1 } .
We observe from the spectra that up to 2010 April 10 , the object was in a hard state .
After that , it went to the hard-intermediate state .
On April 18 , it had a state transition and went to the soft-intermediate state .
On May 15 , another state transition was observed and the source moved to the soft state .

Conclusions : As in the previously fitted outburst sources , this source also showed the tendency of a rapidly increasing QPO frequency ( \nu _ { QPO } ) in a viscous time scale , which can be modeled quite accurately .
In this case , the shock seems to have disappeared at about \sim 172 Schwarzschild radii , unlike in the 2005 outburst of GRO J1655-40 , where the shock disappeared behind the horizon .