<div dir="ltr">Never mind, the answer is the extent_size is the number of sectors (or perhaps it's the number of 512 byte blocks, I'll have to test on 4K sector drives). So in this case 4M and 4M*3840 is the 16G (not 16M which was the 3840*4096). </div><div class="gmail_extra"> <div class="gmail_quote">On Wed, Jul 25, 2018 at 5:37 PM, David F. <<a href="mailto:df7729@gmail.com" target="_blank">df7729@gmail.com</a>> wrote: <blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"><div dir="ltr"><div>I created a test lvm on a 32G UFD with two logical volumes, 15G and 14G. I then looked at the on disk data and most makes since except the extent_count vs extent_size. In this case the extent_size is 8192, and it says the extent sizes are 3840 and 3584, but that * 8192 is double its actual size. * 4096 then it is the size. So how does that work. TIA!! Here's the sample:</div><div> </div><div>test_lvm { id = "xhewgS-UxVF-4qC5-MGXp-ErfX-6SNl-UkCdgz" seqno = 3 format = "lvm2" status = ["RESIZEABLE", "READ", "WRITE"] flags = [] extent_size = 8192 max_lv = 0 max_pv = 0 metadata_copies = 0 physical_volumes { pv0 { id = "XhEzob-g2D5-YcGp-zfz9-39R7-HII6-SITlH9" device = "/dev/sdc" status = ["ALLOCATABLE"] flags = [] dev_size = 62531584 pe_start = 2048 pe_count = 7633 } } logical_volumes { lvm_logvol { id = "IIKGTj-2eYn-5iTk-7KZd-ZMzS-aqYT-kwNgko" status = ["READ", "WRITE", "VISIBLE"] flags = [] creation_time = 1532609310 creation_host = "localhost.localdomain" segment_count = 1 segment1 { start_extent = 0 extent_count = 3840 type = "striped" stripe_count = 1 stripes = [ "pv0", 0 ] } } lvm_logvol2 { id = "dC9wIq-kJ3I-ixLV-A2f9-889Y-qpUr-DdfciL" status = ["READ", "WRITE", "VISIBLE"] flags = [] creation_time = 1532609325 creation_host = "localhost.localdomain" segment_count = 1 segment1 { start_extent = 0 extent_count = 3584 type = "striped" stripe_count = 1 stripes = [ "pv0", 3840 ] } } } } # Generated by LVM2 version 2.02.168(2) (2016-11-30): Thu Jul 26 08:48:45 2018 contents = "Text Format Volume Group" version = 1 description = "" creation_host = "localhost.localdomain" # Linux localhost.localdomain 4.11.8-300.fc26.x86_64 #1 SMP Thu Jun 29 20:09:48 UTC 2017 x86_64 creation_time = 1532609325 # Thu Jul 26 08:48:45 2018</div><div> </div></div> </blockquote></div> </div>