# Jacfwd performance worse after updating the pytorch and functorch is integrated into Pytorch

**URL:** <https://dev-discuss.pytorch.org/t/jacfwd-performance-worse-after-updating-the-pytorch-and-functorch-is-integrated-into-pytorch/1214>\
**Category:** Uncategorized\
**Created:** [April 19, 2023, 3:51pm UTC](https://dev-discuss.pytorch.org/t/jacfwd-performance-worse-after-updating-the-pytorch-and-functorch-is-integrated-into-pytorch/1214 "2023-04-19T15:51:31Z")\
**Posts on this page:** 2\
**Page:** 1

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**Author:** ![JP\_JP\_JP](https://avatars.discourse-cdn.com/v4/letter/j/c77e96/32.png) [@JP\_JP\_JP](https://dev-discuss.pytorch.org/u/JP_JP_JP)\
**Post date:** [April 19, 2023, 3:51pm UTC](https://dev-discuss.pytorch.org/t/jacfwd-performance-worse-after-updating-the-pytorch-and-functorch-is-integrated-into-pytorch/1214/1 "2023-04-19T15:51:31Z")

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Hello, I used to use

```auto
from functorch import jacfwd

```

and Jacfwd takes 3.5s, after the update, I am using

```auto
from torch.func import jacfwd

```

Jacfwd is taking almost 6s, is anyone noticed this?

---

<div class="post-metadata">

**Author:** ![albanD](https://yyz2.discourse-cdn.com/flex036/user_avatar/dev-discuss.pytorch.org/alband/32/9_2.png) [@albanD](https://dev-discuss.pytorch.org/u/albanD)\
**Post date:** [April 21, 2023, 1:39pm UTC](https://dev-discuss.pytorch.org/t/jacfwd-performance-worse-after-updating-the-pytorch-and-functorch-is-integrated-into-pytorch/1214/2 "2023-04-21T13:39:23Z")

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Hi!  
This might not be the best place to ask this kind of question, I would recommend the user forum [discuss.pytorch.org](http://discuss.pytorch.org) for general questions and github issues if you think there is a bug. Also please make sure to share more details on your problem and if possible a script showing exactly the code you run.