This work reports new photometric results of eclipsing cataclysmic variable V617 Sagittarii ( V617 Sgr ) .
We analyzed the orbital period change of V617 Sgr , by employing three new CCD eclipse timings since 2010 along with all the available data from the literature .
It was found that the orbital period of V617 Sgr undergoes an obvious long-term increase , which confirms the result revealed by Steiner et al .
( 2006 ) .
The rate of orbital period increase was calculated to be { \dot { P } } = +2.14 ( 0.05 ) \times 10 ^ { -7 } day/year .
This suggests the lifetime of the secondary star will attain to the end in a timescale of 0.97 \times 10 ^ { 6 } years faster than that predicted previously .
In particular , a cyclic variation with a period of 4.5 year and an amplitude of 2.3 minutes may present in the O-C diagram .
Dominated by the wind-accretion mechanism , high mass transfer from the low mass secondary to the white dwarf is expected to sustain in the V Sge-type star V617 Sgr during its long-term evolution .
The mass transfer rate | \dot { M } _ { tr } | was estimated to be in the range of about 2.2 \times 10 ^ { -7 } to 5.2 \times 10 ^ { -7 } M _ { \odot } yr ^ { -1 } .
Accordingly , the already massive ( \geq 1.2 M _ { \odot } ) white dwarf primary will process stable nuclear burning , accrete a fraction of mass from its companion to reach the standard Chandrasekhar mass limit ( \simeq 1.38 M _ { \odot } ) , and ultimately produce a type Ia supernova ( SN Ia ) within about 4 \sim 8 \times 10 ^ { 5 } years or earlier .