# Long queuing times

**URL:** https://forum.kavli.tudelft.nl/t/long-queuing-times/383
**Category:** Cluster
**Created:** [1 November 2023 16:10 UTC](https://forum.kavli.tudelft.nl/t/long-queuing-times/383 "2023-11-01T16:10:30Z")
**Posts on this page:** 6
**Page:** 1

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### Author: ![Luise](https://forum.kavli.tudelft.nl/letter_avatar_proxy/v4/letter/l/f1d935/32.png) [@Luise](https://forum.kavli.tudelft.nl/u/Luise)
#### Post date: [1 November 2023 16:10 UTC](https://forum.kavli.tudelft.nl/t/long-queuing-times/383/1 "2023-11-01T16:10:30Z")

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Hi 👋 recently the queuing time is much longer than usual. My jobs have been waiting for 3 hours even though the monitoring page suggests that almost all cores (872) are free?

A colleague of mine is facing the same issue.  
Can you help us out here?

Thank you 🙏

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### Author: ![anton-akhmerov](https://forum.kavli.tudelft.nl/user_avatar/forum.kavli.tudelft.nl/anton-akhmerov/32/4_2.png) [@anton-akhmerov](https://forum.kavli.tudelft.nl/u/anton-akhmerov)
#### Post date: [1 November 2023 16:54 UTC](https://forum.kavli.tudelft.nl/t/long-queuing-times/383/2 "2023-11-01T16:54:09Z")

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Hey @Luise, how do you confirm this? Launching an interactive job with `qsub -I` does take long, but it’s 20 seconds rather than hours.

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### Author: ![Luise](https://forum.kavli.tudelft.nl/letter_avatar_proxy/v4/letter/l/f1d935/32.png) [@Luise](https://forum.kavli.tudelft.nl/u/Luise)
#### Post date: [2 November 2023 08:40 UTC](https://forum.kavli.tudelft.nl/t/long-queuing-times/383/3 "2023-11-02T08:40:18Z")

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Hey @anton-akhmerov , I use the `qstat` command to check the status “R” or “Q”. I submitted the following jobs yesterday (lprielinger) and just checked: they are still in the “Q” status.

 ![Screenshot 2023-11-02 at 09.38.43](https://forum.kavli.tudelft.nl/uploads/default/original/1X/b4ccfa91138b0b6a115ffb0e71ceb3e8a5ad0d85.png)

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### Author: ![Luise](https://forum.kavli.tudelft.nl/letter_avatar_proxy/v4/letter/l/f1d935/32.png) [@Luise](https://forum.kavli.tudelft.nl/u/Luise)
#### Post date: [2 November 2023 11:56 UTC](https://forum.kavli.tudelft.nl/t/long-queuing-times/383/4 "2023-11-02T11:56:14Z")

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I think the issue is related to the size of the requested resources – I tried different test submissions now

#PBS -l nodes=1:ppn=25 got the “R” status within a few seconds  
#PBS -l nodes=1:ppn=30 stayed in “Q” for 1min then I cancelled the job

In my initial script I specified #PBS -l nodes=3:ppn=30. I wonder if this is simply too large, but then previous submissions of the same size were usually accepted?

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### Author: ![anton-akhmerov](https://forum.kavli.tudelft.nl/user_avatar/forum.kavli.tudelft.nl/anton-akhmerov/32/4_2.png) [@anton-akhmerov](https://forum.kavli.tudelft.nl/u/anton-akhmerov)
#### Post date: [2 November 2023 16:13 UTC](https://forum.kavli.tudelft.nl/t/long-queuing-times/383/5 "2023-11-02T16:13:19Z")

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You seem to be asking for 30 cpu cores per node. Each node has 2x10 core CPUs with 2x hyperthreading, so they show up as 40 CPU cores. I believe that for practical purposes using more than the amount of physical cores does not provide speedup, and therefore I believe you’re better off not using more than `ppn=20`. Still, I don’t actually know why `ppn=30` doesn’t run unless all nodes have more than 10 cores reserved.

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### Author: ![Luise](https://forum.kavli.tudelft.nl/letter_avatar_proxy/v4/letter/l/f1d935/32.png) [@Luise](https://forum.kavli.tudelft.nl/u/Luise)
#### Post date: [2 November 2023 21:22 UTC](https://forum.kavli.tudelft.nl/t/long-queuing-times/383/6 "2023-11-02T21:22:23Z")

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Thanks, I followed your instructions and all jobs are getting executed again. 🙂