multi_bench: run smaller pipeline by default
multi_bench: run smaller pipeline by default

benfleis/tchannel,Zirpon/tchannel,vanloswang/tchannel,sasa233/tchannel,i/tchannel,bunnyblue/tchannel,sasa233/tchannel,bunnyblue/tchannel,hustxiaoc/tchannel,Zirpon/tchannel,RyanTech/tchannel,RyanTech/tchannel,savaki/tchannel,benfleis/tchannel,i/tchannel,benfleis/tchannel,bunnyblue/tchannel,vanloswang/tchannel,chenwenbin928/tchannel,Zirpon/tchannel,savaki/tchannel,chenwenbin928/tchannel,hustxiaoc/tchannel,savaki/tchannel,sasa233/tchannel,vanloswang/tchannel,i/tchannel,RyanTech/tchannel,chenwenbin928/tchannel,hustxiaoc/tchannel