Performance improvement in shiny app

[Biswarup]

I have a dashboard built with shiny and off late its responding a bit sluggishly . I have not changed anything that could impact performance as far as I understand . How would I check which portions of the code is making the app sluggish .

The link for the app is here 

https://bisg.shinyapps.io/dashboardapp/

and if someone want to take a look at the code its here 

https://github.com/creepystranger/VancouverCrimeDashboard/blob/master/app.R

[Ger Inberg]

I have good experiences with the package profvis, https://rstudio.github.io/profvis/

It profiles your R code and visualizes the result, can be very helpful to discover parts of the code that are slow

best,Ger