# CSV : problem to write big dataframes

**URL:** <https://discourse.julialang.org/t/csv-problem-to-write-big-dataframes/17343>\
**Category:** Data\
**Tags:** csv\
**Created:** [November 9, 2018, 3:17pm UTC](https://discourse.julialang.org/t/csv-problem-to-write-big-dataframes/17343 "2018-11-09T15:17:39Z")\
**Posts on this page:** 1\
**Showing post:** 20

<div class="post-metadata">

**Author:** ![Tamas\_Papp](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/tamas_papp/32/25949_2.png) [@Tamas\_Papp](https://discourse.julialang.org/u/Tamas_Papp)\
**Post date:** [May 29, 2023, 11:43am UTC](https://discourse.julialang.org/t/csv-problem-to-write-big-dataframes/17343/20 "2023-05-29T11:43:27Z")

</div>

Please make an MWE that reproduces the problem, and ideally report it as an issue in the CSV repository. I cannot reproduce it with a simple example, eg

```julia
using CSV, DataFrames
N = 10^8
df = DataFrame(; a = rand(Int, N), b = rand(Float64, N), c = rand('a':'z', N))
dst = "/tmp/data.csv"
@time CSV.write(dst, df)
@show filesize(dst) / 2^30 # file size in Gb

```

takes 45s on my laptop, creating an almost 4GB file (using an SSD). I find this reasonable.

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