# Customizing SharedArray
**URL:** https://discourse.julialang.org/t/customizing-sharedarray/62933
**Category:** General Usage
**Tags:** parallel
**Created:** [June 15, 2021, 9:30am UTC](https://discourse.julialang.org/t/customizing-sharedarray/62933 "2021-06-15T09:30:52Z")
**Posts on this page:** 5
**Page:** 1
### Author:  [@FredericN](https://discourse.julialang.org/u/FredericN)
#### Post date: [June 15, 2021, 9:30am UTC](https://discourse.julialang.org/t/customizing-sharedarray/62933/1 "2021-06-15T09:30:52Z")
When creating a SharedArray as in
using SharedArrays
using Distributed
addprocs(4)
a = SharedArray{Float64}(40)
the partitioning of entries is made automatically. Does anyone knows if it is possible to set my own partitioning of the data ? Related question: where can I find a full documentation of the package SharedArrays?
Many thanks.
---
### Author:  [@nilshg](https://discourse.julialang.org/u/nilshg)
#### Post date: [June 15, 2021, 10:03am UTC](https://discourse.julialang.org/t/customizing-sharedarray/62933/2 "2021-06-15T10:03:34Z")
`SharedArrays` is a standard library, so the documentation is part of the documentation of the core language. Relevant entries:
[https://docs.julialang.org/en/v1/stdlib/SharedArrays/](https://docs.julialang.org/en/v1/stdlib/SharedArrays/)
and
[https://docs.julialang.org/en/v1/manual/distributed-computing/#man-shared-arrays](https://docs.julialang.org/en/v1/manual/distributed-computing/#man-shared-arrays)
---
### Author:  [@FredericN](https://discourse.julialang.org/u/FredericN)
#### Post date: [June 15, 2021, 12:14pm UTC](https://discourse.julialang.org/t/customizing-sharedarray/62933/3 "2021-06-15T12:14:35Z")
Thanks for the links but I am looking for a detailed documentation if it exists.
---
### Author:  [@jpsamaroo](https://discourse.julialang.org/u/jpsamaroo)
#### Post date: [June 15, 2021, 12:33pm UTC](https://discourse.julialang.org/t/customizing-sharedarray/62933/4 "2021-06-15T12:33:54Z")
> [@FredericN](#):
>
> the partitioning of entries is made automatically
What do you mean by “partitioning” here? The SharedArray is accessible to all processes that it’s mapped on equally, i.e. it is not a chunked array. You can change which workers have the array mapped with the `pids` kwarg.
If you mean that you want to be able to initialize it differently, you can just do that after you create it.
> [@FredericN](#):
>
> Thanks for the links but I am looking for a detailed documentation if it exists.
I suppose it’s not super well documented since it’s a pretty simple mechanism; I found the code pretty enlightening, so maybe you will too. If you find anything that’s not documented that you think is important for using a SharedArray, you’re welcome to open a PR to improve the docs 🙂
---
### Author:  [@FredericN](https://discourse.julialang.org/u/FredericN)
#### Post date: [June 15, 2021, 1:44pm UTC](https://discourse.julialang.org/t/customizing-sharedarray/62933/5 "2021-06-15T13:44:07Z")
By partitioning, I mean I want to impose the number of local indices for each worker.