David Teigland 79c4971210 label_scan: remove extra label scan and read for orphan PVs ... When process_each_pv() calls vg_read() on the orphan VG, the internal implementation was doing an unnecessary lvmcache_label_scan() and two unnecessary label_read() calls on each orphan. Some of those unnecessary label scans/reads would sometimes be skipped due to caching, but the code was always doing at least one unnecessary read on each orphan. The common format_text case was also unecessarily calling into the format-specific pv_read() function which actually did nothing. By analyzing each case in which vg_read() was being called on the orphan VG, we can say that all of the label scans/reads in vg_read_orphans are unnecessary: 1. reporting commands: the information saved in lvmcache by the original label scan can be reported. There is no advantage to repeating the label scan on the orphans a second time before reporting it. 2. pvcreate/vgcreate/vgextend: these all share a common implementation in pvcreate_each_device(). That function already rescans labels after acquiring the orphan VG lock, which ensures that the command is using valid lvmcache information.		2018-04-20 11:22:45 -05:00
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lvmcache.c	label_scan: remove extra label scan and read for orphan PVs	2018-04-20 11:22:45 -05:00
lvmcache.h	label_scan: remove extra label scan and read for orphan PVs	2018-04-20 11:22:45 -05:00
lvmetad.c	lvmetad: use new label_scan for update from pvscan	2018-04-20 11:22:43 -05:00
lvmetad.h	lvmetad: two phase vg_remove	2016-06-28 02:30:36 +01:00