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Subject: Re: Strange behavior after running under high load
To: freebsd-current@freebsd.org
References: <58bea0f0-5c3d-4263-ebee-f939a7e169e9@freebsd.org>
From: Andrea Venturoli <ml@netfence.it>
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Date: Mon, 29 Mar 2021 08:45:45 +0200
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On 3/28/21 4:39 PM, Stefan Esser wrote:
> After a period of high load, my now idle system needs 4 to 10 seconds to
> run any trivial command - even after 20 minutes of no load ...

High CPU load or high disk load?
ZFS? Snapshots?
12.x? 13.x?

I've seen something similar: after a high load period, system crawled so 
much that services were not answering in a reasonable time (e.g. mail 
would fail with "no such mailbox"!).
Even rebooting didn't fix it, until I deleted some autosnapshots.
top or other tools would show no disk activity, although the disks were 
working as mad.

Not sure it's the same case you experienced, though.