# The benefit of Accelerate mode, when and where to use it ?

**URL:** <https://forum.ansible.com/t/the-benefit-of-accelerate-mode-when-and-where-to-use-it/14210>\
**Category:** Ansible Project\
**Created:** [December 23, 2013, 7:34pm UTC](https://forum.ansible.com/t/the-benefit-of-accelerate-mode-when-and-where-to-use-it/14210 "2013-12-23T19:34:38Z")\
**Posts on this page:** 5\
**Page:** 1

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**Author:** ![PePe\_Amengual](https://avatars.discourse-cdn.com/v4/letter/p/3e96dc/32.png) [@PePe\_Amengual](https://forum.ansible.com/u/PePe_Amengual)\
**Post date:** [December 23, 2013, 7:34pm UTC](https://forum.ansible.com/t/the-benefit-of-accelerate-mode-when-and-where-to-use-it/14210/1 "2013-12-23T19:34:38Z")

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Hi.

I have been playing with accelerate mode and serial options to see if I can speed up the deployment process. For now I’m just deploying to 8 servers but once in prod I will deploying to 40 servers.

In my tests I realize that asccelerate mode is much slower than default for a quite a significant number like around 350 seconds more.

basically my playbook uses rsync to deploy like so :

command: rsync -rthim {{codecache\_dir}}/{{project\_name}}/ {{releases\_path}}/{{project\_name}}/{{release\_tag}}/

Base on my results now I’m wondering why is accelerate mode slower than the default options ?

is this a good use case to use accelerate mode ?

is good when sending bigger files ?

Thanks.

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**Author:** ![Brian\_Coca1](https://avatars.discourse-cdn.com/v4/letter/b/278dde/32.png) [@Brian\_Coca1](https://forum.ansible.com/u/Brian_Coca1)\
**Post date:** [December 23, 2013, 7:41pm UTC](https://forum.ansible.com/t/the-benefit-of-accelerate-mode-when-and-where-to-use-it/14210/2 "2013-12-23T19:41:02Z")

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It is more efficient for large number of hosts(100s to 1000s) and playbooks with many tasks, if you have only one task the setup cost will be counterproductive.

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**Author:** ![PePe\_Amengual](https://avatars.discourse-cdn.com/v4/letter/p/3e96dc/32.png) [@PePe\_Amengual](https://forum.ansible.com/u/PePe_Amengual)\
**Post date:** [December 23, 2013, 9:04pm UTC](https://forum.ansible.com/t/the-benefit-of-accelerate-mode-when-and-where-to-use-it/14210/3 "2013-12-23T21:04:03Z")

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I already have it setup and it was really simple but is it supposed to be faster ?

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**Author:** ![Brian\_Coca1](https://avatars.discourse-cdn.com/v4/letter/b/278dde/32.png) [@Brian\_Coca1](https://forum.ansible.com/u/Brian_Coca1)\
**Post date:** [December 23, 2013, 9:11pm UTC](https://forum.ansible.com/t/the-benefit-of-accelerate-mode-when-and-where-to-use-it/14210/4 "2013-12-23T21:11:32Z")

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not your setup costs, the (time) cost of setting up the socket server on the ‘targets’ and networking them, for you its just a connection: .

it IS faster when dealing with average to large playbooks, but it stands to reason that it will be slower for a single task, as it uses ssh to connect initially to setup the accelerated socket server and then run the task, vs ssh and running the task.

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**Author:** ![Michael\_DeHaan2](https://avatars.discourse-cdn.com/v4/letter/m/da6949/32.png) [@Michael\_DeHaan2](https://forum.ansible.com/u/Michael_DeHaan2)\
**Post date:** [December 23, 2013, 9:47pm UTC](https://forum.ansible.com/t/the-benefit-of-accelerate-mode-when-and-where-to-use-it/14210/5 "2013-12-23T21:47:15Z")

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Yep, it’s primarily useful for _longer_ playbooks, rather than a parallelism thing (completely unrelated to the number of hosts), and shows greater dividends over more latent connections.

All being said the alternate SSH transport being developed now (-c ssh\_alt, to become the new -c ssh once completed with testing) may obviate the need for accelerate mode in many cases.