# Overlapping AMR support in vtkHDF

**URL:** https://discourse.vtk.org/t/overlapping-amr-support-in-vtkhdf/7868
**Category:** Development
**Tags:** proposal
**Created:** [February 18, 2022, 8:04am UTC](https://discourse.vtk.org/t/overlapping-amr-support-in-vtkhdf/7868 "2022-02-18T08:04:32Z")
**Posts on this page:** 1
**Showing post:** 5

<div class="post-metadata">

### Author: ![Francois\_Mazen](https://discourse.vtk.org/user_avatar/discourse.vtk.org/francois_mazen/32/3290_2.png) [@Francois\_Mazen](https://discourse.vtk.org/u/Francois_Mazen)
#### Post date: [February 23, 2022, 8:22am UTC](https://discourse.vtk.org/t/overlapping-amr-support-in-vtkhdf/7868/5 "2022-02-23T08:22:20Z")

</div>

Thanks for your feedback, it makes sense that lots of small attributes will be slower to read than a big attribute. The whole point of using hdf5 is performance, so your input is very valuable.

In your proposal, we should add extra information in the `AMRBox` Dataset which correspond to the underlying image data: WholeExtent, Origin, Spacing, Direction and Piece Extent if applicable. In hdf5 it should be attributes under a group.

Hence we may need a `GROUP AMRBoxes` with several `GROUP AMRBox` with all the required data as attributes. Unless you think it could also be a bottleneck?

@danlipsa any thought?

---

_[View the full topic](https://discourse.vtk.org/t/overlapping-amr-support-in-vtkhdf/7868)._