2 Commits

Author	SHA1	Message	Date
David Teigland	f8b52f2763	fix multipath component detection for multiple holders ... sysfs-based multipath component detection quit if a device had multiple holders, and in this case would fail to detect a device was an mpath component.	2021-07-13 11:11:23 -05:00
David Teigland	9048565093	devices: rework libudev usage ... related to config settings: obtain_device_info_from_udev (controls if lvm gets a list of devices from readdir /dev or from libudev) external_device_info_source (controls if lvm asks libudev for device information) . Make the obtain_device_list_from_udev setting affect only the choice of readdir /dev vs libudev. The setting no longer controls if udev is used for device type checks. . Change obtain_device_list_from_udev default to 0. This helps avoid boot timeouts due to slow libudev queries, avoids reported failures from udev_enumerate_scan_devices, and avoids delays from "device not initialized in udev database" errors. Even without errors, for a system booting with 1024 PVs, lvm2-pvscan times improve from about 100 sec to 15 sec, and the pvscan command from about 64 sec to about 4 sec. . For external_device_info_source="none", remove all libudev device info queries, and use only lvm native device info. . For external_device_info_source="udev", first check lvm native device info, then check libudev info. . Remove sleep/retry loop when attempting libudev queries for device info. udev info will simply be skipped if it's not immediately available. . Only set up a libdev connection if it will be used by obtain_device_list_from_udev/external_device_info_source. . For native multipath component detection, use /etc/multipath/wwids. If a device has a wwid matching an entry in the wwids file, then it's considered a multipath component. This is necessary to natively detect multipath components when the mpath device is not set up.	2021-07-13 11:11:23 -05:00