gc(verbose = TRUE)

# basic memory
memory.size(max=F)

library(arrow, warn.conflicts = FALSE)

# Memory after loading the arrow library with memory.size
memory.size(max=F)

# bytes_allocated after loading the arrow library
default_memory_pool()$bytes_allocated

# max_memory after loading the arrow library
default_memory_pool()$max_memory

library(dplyr)

# Memory after loading the dplyr library with memory.size
memory.size(max=F)

# bytes_allocated after loading the dplyr library
default_memory_pool()$bytes_allocated

# max_memory after loading the dplyr library
default_memory_pool()$max_memory

df <- data.frame(
  col1 = rnorm(1000000),
  col2 = rnorm(1000000),
  col3 = runif(1000000),
  col4 = sample(1:999, size = 1000000, replace = T),
  col5 = sample(c("GroupA", "GroupB"), size = 1000000, replace = T),
  col6 = sample(c("TypeA", "TypeB"), size = 1000000, replace = T)
)

# Memory after df object creation
memory.size(max=F)

# bytes_allocated after df object creation
default_memory_pool()$bytes_allocated

# max_memory after df object creation
default_memory_pool()$max_memory

arrow::write_dataset(
  df,
  paste0(Sys.getenv("USERPROFILE"),"/ExProblemeGc"),
  format = "parquet"
)

# Memory after writing to disk
memory.size(max=F)

# bytes_allocated after writing to disk
default_memory_pool()$bytes_allocated

# max_memory after writing to disk
default_memory_pool()$max_memory

rm(df)

# Memory after deletion df
memory.size(max=F)

# bytes_allocated after deletion df
default_memory_pool()$bytes_allocated

# max_memory after deletion df
default_memory_pool()$max_memory

gc(verbose = TRUE)

# Memory after gc(verbose = TRUE)
memory.size(max=F)

# bytes_allocated after gc(verbose = TRUE)
default_memory_pool()$bytes_allocated

# max_memory after gc(verbose = TRUE)
default_memory_pool()$max_memory

gc(verbose = TRUE)

# Memory after gc(verbose = TRUE)
memory.size(max=F)

# bytes_allocated after gc(verbose = TRUE)
default_memory_pool()$bytes_allocated

# max_memory after gc(verbose = TRUE)
default_memory_pool()$max_memory

ds <- arrow::open_dataset(paste0(Sys.getenv("USERPROFILE"),"/ExProblemeGc"))

# Memory after ds creation
memory.size(max=F)

# bytes_allocated after ds creation
default_memory_pool()$bytes_allocated

# max_memory after ds creation
default_memory_pool()$max_memory

req <-
  ds %>%
  collect()

# Memory after req creation
memory.size(max=F)

# bytes_allocated after req creation
default_memory_pool()$bytes_allocated

# max_memory after req creation
default_memory_pool()$max_memory

rm(req)

# Memory after deletion req
memory.size(max=F)

# bytes_allocated after deletion req
default_memory_pool()$bytes_allocated

# max_memory after deletion req
default_memory_pool()$max_memory

gc(verbose = TRUE)

# Memory after gc(verbose = TRUE)
memory.size(max=F)

# bytes_allocated after gc(verbose = TRUE)
default_memory_pool()$bytes_allocated

# max_memory after gc(verbose = TRUE)
default_memory_pool()$max_memory

gc(verbose = TRUE)

# bytes_allocated after gc(verbose = TRUE)
default_memory_pool()$bytes_allocated

# max_memory after gc(verbose = TRUE)
default_memory_pool()$max_memory

# Memory after gc(verbose = TRUE)
memory.size(max=F)

rm(ds)

# Memory after deletion df
memory.size(max=F)

# bytes_allocated after deletion df
default_memory_pool()$bytes_allocated

# max_memory after deletion df
default_memory_pool()$max_memory

gc(verbose = TRUE)

# Memory after gc(verbose = TRUE)
memory.size(max=F)

# bytes_allocated after gc(verbose = TRUE)
default_memory_pool()$bytes_allocated

# max_memory after gc(verbose = TRUE)
default_memory_pool()$max_memory

gc(verbose = TRUE)

# Memory after gc(verbose = TRUE)
memory.size(max=F)

# bytes_allocated after gc(verbose = TRUE)
default_memory_pool()$bytes_allocated

# max_memory after gc(verbose = TRUE)
default_memory_pool()$max_memory