REDROOM

Create

Preview: kdump-udev-throttler Size: 1.41 KB

/usr/lib/udev/kdump-udev-throttler

#!/bin/bash
# This util helps to reduce the workload of kdump service restarting
# on udev event. When hotplugging memory / CPU, multiple udev
# events may be triggered concurrently, and obviously, we don't want
# to restart kdump service for each event.

# This script will be called by udev, and make sure kdump service is
# restart after all events we are watching are settled.

# On each call, this script will update try to aquire the $throttle_lock
# The first instance acquired the file lock will keep waiting for events
# to settle and then reload kdump. Other instances will just exit
# In this way, we can make sure kdump service is restarted immediately
# and for exactly once after udev events are settled.

throttle_lock="/var/lock/kdump-udev-throttle"

exec 9>$throttle_lock
if [ $? -ne 0 ]; then
        echo "Failed to create the lock file! Fallback to non-throttled kdump service restart"
        /bin/kdumpctl reload
        exit 1
fi

flock -n 9
if [ $? -ne 0 ]; then
        echo "Throttling kdump restart for concurrent udev event"
        exit 0
fi

# Wait for at least 1 second, at most 4 seconds for udev to settle
# Idealy we will have a less than 1 second lag between udev events settle
# and kdump reload
sleep 1 && udevadm settle --timeout 3

# Release the lock, /bin/kdumpctl will block and make the process
# holding two locks at the same time and we might miss some events
exec 9>&-

/bin/kdumpctl reload

exit 0

Name	Size	Perms	Modified	Actions
hwdb.d DIR	-	drwxr-xr-x	2026-01-27 23:01:13	Edit Download recursive recursive
rules.d DIR	-	drwxr-xr-x	2026-02-03 09:56:06	Edit Download recursive recursive
ata_id	40.73 KB	lrwxr-xr-x	2026-01-26 09:30:39	Edit Download recursive recursive
cdrom_id	32.51 KB	lrwxr-xr-x	2026-01-26 09:30:39	Edit Download recursive recursive
collect	20.57 KB	lrwxr-xr-x	2026-01-26 09:30:39	Edit Download recursive recursive
fc_wwpn_id	1.10 KB	lrwxr-xr-x	2022-10-08 11:49:23	Edit Download recursive recursive
fido_id	16.43 KB	lrwxr-xr-x	2026-01-26 09:30:39	Edit Download recursive recursive
kdump-udev-throttler	1.41 KB	lrwxr-xr-x	2024-09-24 08:36:00	Edit Download recursive recursive
kpartx_id	2.33 KB	lrwxr-xr-x	2025-04-22 01:55:39	Edit Download recursive recursive
mtd_probe	12.41 KB	lrwxr-xr-x	2026-01-26 09:30:39	Edit Download recursive recursive
prefixdevname	1.46 MB	lrwxr-xr-x	2019-12-16 19:52:38	Edit Download recursive recursive
rename_device	16.46 KB	lrwxr-xr-x	2025-11-04 09:19:14	Edit Download recursive recursive
scsi_id	53.70 KB	lrwxr-xr-x	2026-01-26 09:30:39	Edit Download recursive recursive
v4l_id	12.00 KB	lrwxr-xr-x	2026-01-26 09:30:39	Edit Download recursive recursive

Directory Contents