This is interesting, and I understand your explaination Ray... But, how can I figure out how much data is on each PVs?? I have something similar setup, and I have scripts (and cacti) to see disk IO for each PVs, but I would really like to see how much data is on each PV... Thank you, > Date: Wed, 11 Aug 2010 01:10:31 -0500 > From: Ray Morris <support@bettercgi.com> > To: LVM general discussion and development <linux-lvm@redhat.com> > Subject: Re: calculating free capacity from pvdisplay and > lvdisplay > Message-ID: <1281507031.21952.1@raydesk1.bettercgi.com> > Content-Type: text/plain; charset=us-ascii; DelSp=Yes; Format=Flowed > >> B. Thus the total full space would come to 4.89 TB. But the sum of >> full >> space of all my LV's is only around 3 TB (based on the output of df) > > It's the same thing as making a new partition covering your whole drive, > then wondering why fdisk says you can't make another partition. Just > because you haven't stored files in that partition, it's still takes > up the whole drive. > > df shows that your LVs take up 8.6TB: 6TB + 600 GB + 2 TB. > Therefore, you are using 8.6TB of disk space for those LVs. > Some of the space WITHIN each LV might not be used for files, > but it has been dedicated to that LV. > > df also shows that the filesystems on the LVs have free space for > more files. So you can put more files on those LVs, which is a > different thing than having space to make more LVs. > > I'm not good at explaining things, so sometimes I try explaining three > different ways. I have six cereal boxes, each half empty. I put the > boxes in a bag. The bag is now full. The cereal boxes may not be full, > but they fill up the bag. The cereal boxes are your half empty LVs and > the bag is your drives. > > Layers: > > hard drive > partition (can be skipped) > physical volume > volume group > logical volume > file system > -- > Ray Morris > support@bettercgi.com > > Strongbox - The next generation in site security: > http://www.bettercgi.com/strongbox/ > > Throttlebox - Intelligent Bandwidth Control > http://www.bettercgi.com/throttlebox/ > > Strongbox / Throttlebox affiliate program: > http://www.bettercgi.com/affiliates/user/register.php > > > On 08/10/2010 09:25:15 PM, Rahul Nabar wrote: >> Some of the physical volumes show "Allocatable yes (but >> full)" while others don't. How does one relate this to the actual >> capacity? THe reason I am confused is that 3 of my PV's show up as >> full and each is 1.63 TB. Thus the total full space would come to 4.89 >> TB. But the sum of full space of all my LV's is only around 3 TB >> (based on the output of df) >> >> I've reproduced the outputs of pvdisplay, lvdisplay and df below. >> >> I'm confused! Any pointers? >> >> -- >> Rahul >> >> >> [root@eustorage ~]# pvdisplay >> --- Physical volume --- >> PV Name /dev/sdb >> VG Name euclid_highperf_storage >> PV Size 1.63 TB / not usable 4.00 MB >> Allocatable yes (but full) >> PE Size (KByte) 4096 >> Total PE 428351 >> Free PE 0 >> Allocated PE 428351 >> PV UUID wDdbmP-2n5m-98HD-Ewqk-Q3y0-lnMf-rsaVXt >> >> --- Physical volume --- >> PV Name /dev/sdc >> VG Name euclid_highperf_storage >> PV Size 1.63 TB / not usable 4.00 MB >> Allocatable yes (but full) >> PE Size (KByte) 4096 >> Total PE 428351 >> Free PE 0 >> Allocated PE 428351 >> PV UUID 75i75q-2rec-2FMf-eyPa-W0nF-zFHH-PIAvvc >> >> --- Physical volume --- >> PV Name /dev/sdd >> VG Name euclid_highperf_storage >> PV Size 1.63 TB / not usable 4.00 MB >> Allocatable yes (but full) >> PE Size (KByte) 4096 >> Total PE 428351 >> Free PE 0 >> Allocated PE 428351 >> PV UUID vo2Jh2-PfFC-eOj4-GYnP-Jx1I-Sisu-2nY4lC >> >> --- Physical volume --- >> PV Name /dev/sde >> VG Name euclid_highperf_storage >> PV Size 1.63 TB / not usable 4.00 MB >> Allocatable yes >> PE Size (KByte) 4096 >> Total PE 428351 >> Free PE 38140 >> Allocated PE 390211 >> PV UUID EK7cvF-IZjf-PJVw-d2RR-lCdt-kOSD-iqFtOf >> >> --- Physical volume --- >> PV Name /dev/sdf >> VG Name euclid_highperf_storage >> PV Size 1.63 TB / not usable 4.00 MB >> Allocatable yes >> PE Size (KByte) 4096 >> Total PE 428351 >> Free PE 140607 >> Allocated PE 287744 >> PV UUID fQXN8S-HhYu-weoq-kbuz-BrxZ-6WQk-6ydBDw >> >> --- Physical volume --- >> PV Name /dev/sdg >> VG Name euclid_highperf_storage >> PV Size 1.63 TB / not usable 4.00 MB >> Allocatable yes >> PE Size (KByte) 4096 >> Total PE 428351 >> Free PE 140607 >> Allocated PE 287744 >> PV UUID i7GD1d-rbd2-efKd-uK3u-D3S2-BxJv-UkrNve >> >> [root@eustorage ~]# df -h >> Filesystem Size Used Avail Use% Mounted on >> /dev/sda2 76G 8.6G 64G 12% / >> /dev/sda6 19G 365M 17G 3% /var >> /dev/sda5 15G 165M 14G 2% /tmp >> /dev/sda1 487M 17M 445M 4% /boot >> tmpfs 24G 0 24G 0% /dev/shm >> /dev/mapper/euclid_highperf_storage-LV_home >> 6.0T 1.4T 4.4T 24% /home >> /dev/mapper/euclid_highperf_storage-LV_export >> 591G 17G 550G 3% /opt >> /dev/mapper/euclid_highperf_storage-LV_polhome >> 2.0T 1.5T 386G 80% /polhome >> [root@eustorage ~]# lvdisplay >> --- Logical volume --- >> LV Name /dev/euclid_highperf_storage/LV_home >> VG Name euclid_highperf_storage >> LV UUID gu7yo1-TYYr-ucHG-QSDk-y8HD-ETrs-Z5kCk9 >> LV Write Access read/write >> LV Status available >> # open 1 >> LV Size 6.00 TB >> Current LE 1572864 >> Segments 1 >> Allocation inherit >> Read ahead sectors auto >> - currently set to 1536 >> Block device 253:0 >> >> --- Logical volume --- >> LV Name /dev/euclid_highperf_storage/LV_export >> VG Name euclid_highperf_storage >> LV UUID 1lktLy-Hgn3-qS1m-41VJ-5kNY-DMyb-1ri4Th >> LV Write Access read/write >> LV Status available >> # open 1 >> LV Size 600.00 GB >> Current LE 153600 >> Segments 1 >> Allocation inherit >> Read ahead sectors auto >> - currently set to 1536 >> Block device 253:1 >> >> --- Logical volume --- >> LV Name /dev/euclid_highperf_storage/LV_polhome >> VG Name euclid_highperf_storage >> LV UUID xqpOX5-HFey-H0qi-NgjP-NVS7-FwDb-zbiK8m >> LV Write Access read/write >> LV Status available >> # open 1 >> LV Size 2.00 TB >> Current LE 524288 >> Segments 4 >> Allocation inherit >> Read ahead sectors auto >> - currently set to 256 >> Block device 253:2 >> >> _______________________________________________ >> linux-lvm mailing list >> linux-lvm@redhat.com >> https://www.redhat.com/mailman/listinfo/linux-lvm >> read the LVM HOW-TO at http://tldp.org/HOWTO/LVM-HOWTO/ >> >> > _______________________________________________ linux-lvm mailing list linux-lvm@redhat.com https://www.redhat.com/mailman/listinfo/linux-lvm read the LVM HOW-TO at http://tldp.org/HOWTO/LVM-HOWTO/
