hi,
i''m using a zvol someone else created (and then used as
an iSCSI Target, via: "iscsitadm ... -b /dev/zvol ...").
I see that AVAIL has a size of 33GB, yet the VOLSIZE is 24GB ;
# zfs list -t volume -o name,avail,used,volsize iscsi-pool/log_1_1
NAME AVAIL USED VOLSIZE
iscsi-pool/log_1_1 33.7G 24.4G 24.4G
I debugged ''format'', and it received a size of 24GB from
Sun''s
iSCSI Target implementation. ''format'' did a READ-CAPACITY
(scsi)
cmd and was returned "24GB".
why does 33GB show as AVAIL ? should i be expecting 33GB''s worth
of usable disk space? ...or does AVAIL (for some weird reason also)
include metadata) ??
# zdb -v iscsi-pool/log_1_1
Dataset iscsi-pool/log_1_1 [ZVOL], ID 117, cr_txg 74, 54.0K, 3 objects
Object lvl iblk dblk lsize asize type
0 7 16K 16K 16K 14.0K DMU dnode
1 4 16K 8K 24.4G 38.0K zvol object
<<<<<<
2 1 16K 512 512 1K zvol prop
thanks
/andrew
--
This message posted from opensolaris.org
Cindy.Swearingen at Sun.COM
2009-Aug-03 17:02 UTC
[zfs-discuss] how is size of Volume computed?
Hi Andrew, The AVAIL column indicates the pool size, not the volsize in this example. In your case, the iscsi-pool/log_1_1 volume is 24 GB in size and the remaining pool space is 33.7G. The 33.7G reflects your pool space, not your volume size. The sizing is easier to see if you include the zpool list output and a fuller zfs list output. Cindy On 08/03/09 10:35, Andrew A. Rutz wrote:> hi, > > i''m using a zvol someone else created (and then used as > an iSCSI Target, via: "iscsitadm ... -b /dev/zvol ..."). > > I see that AVAIL has a size of 33GB, yet the VOLSIZE is 24GB ; > > # zfs list -t volume -o name,avail,used,volsize iscsi-pool/log_1_1 > NAME AVAIL USED VOLSIZE > iscsi-pool/log_1_1 33.7G 24.4G 24.4G > > > I debugged ''format'', and it received a size of 24GB from Sun''s > iSCSI Target implementation. ''format'' did a READ-CAPACITY (scsi) > cmd and was returned "24GB". > > why does 33GB show as AVAIL ? should i be expecting 33GB''s worth > of usable disk space? ...or does AVAIL (for some weird reason also) > include metadata) ?? > > # zdb -v iscsi-pool/log_1_1 > Dataset iscsi-pool/log_1_1 [ZVOL], ID 117, cr_txg 74, 54.0K, 3 objects > > Object lvl iblk dblk lsize asize type > 0 7 16K 16K 16K 14.0K DMU dnode > 1 4 16K 8K 24.4G 38.0K zvol object <<<<<< > 2 1 16K 512 512 1K zvol prop > > > thanks > /andrew
Andrew.Rutz at Sun.COM
2009-Aug-03 17:26 UTC
[zfs-discuss] how is size of Volume computed?
hi cindy, tnx for the response. here''s every attr that has "size" in it: :-) # zlvsz iscsi-pool/log_1_1 NAME AVAIL REFER USED QUOTA RECSIZE REFQUOTA REFRESERV RESERV VOLBLOCK VOLSIZE iscsi-pool/log_1_1 33.7G 54K 24.4G - - - 24.4G none 8K 24.4G (btw, i know the VOLSIZE/USED value of 24.4G derives from the Sun disk label, because I wrote the label "by hand" using ''format'' and iSCSI Target code). the scsi READ CAPACITY command returns "24.4GB". is the (33GB-24GB) space used by zfs as metadata? and/or: why wouldn''t the READ-CAPACITY command return a value that''s a lot closer to 33GB? tnx /andrew (I work in Sun''s Sustaining group) On 08/03/09 12:02, Cindy.Swearingen at Sun.COM wrote:> Hi Andrew, > > The AVAIL column indicates the pool size, not the volsize > in this example. > > In your case, the iscsi-pool/log_1_1 volume is 24 GB in size > and the remaining pool space is 33.7G. The 33.7G reflects > your pool space, not your volume size. > > The sizing is easier to see if you include the zpool list > output and a fuller zfs list output. > > Cindy > > On 08/03/09 10:35, Andrew A. Rutz wrote: >> hi, >> >> i''m using a zvol someone else created (and then used as >> an iSCSI Target, via: "iscsitadm ... -b /dev/zvol ..."). >> >> I see that AVAIL has a size of 33GB, yet the VOLSIZE is 24GB ; >> >> # zfs list -t volume -o name,avail,used,volsize iscsi-pool/log_1_1 >> NAME AVAIL USED VOLSIZE >> iscsi-pool/log_1_1 33.7G 24.4G 24.4G >> >> >> I debugged ''format'', and it received a size of 24GB from Sun''s >> iSCSI Target implementation. ''format'' did a READ-CAPACITY (scsi) >> cmd and was returned "24GB". >> >> why does 33GB show as AVAIL ? should i be expecting 33GB''s worth >> of usable disk space? ...or does AVAIL (for some weird reason also) >> include metadata) ?? >> >> # zdb -v iscsi-pool/log_1_1 >> Dataset iscsi-pool/log_1_1 [ZVOL], ID 117, cr_txg 74, 54.0K, 3 objects >> >> Object lvl iblk dblk lsize asize type >> 0 7 16K 16K 16K 14.0K DMU dnode >> 1 4 16K 8K 24.4G 38.0K zvol object <<<<<< >> 2 1 16K 512 512 1K zvol prop >> >> >> thanks >> /andrew > _______________________________________________ > zfs-discuss mailing list > zfs-discuss at opensolaris.org > http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
Cindy.Swearingen at Sun.COM
2009-Aug-03 17:49 UTC
[zfs-discuss] how is size of Volume computed?
Andrew, Take a look at your zpool list output, which identifies the size of your iscsi-pool pool. Regardless of how the volume size was determined, your remaining pool size is still 33GB and yes, some of it is used for metadata. cs On 08/03/09 11:26, Andrew.Rutz at Sun.COM wrote:> hi cindy, > tnx for the response. > > here''s every attr that has "size" in it: :-) > > # zlvsz iscsi-pool/log_1_1 > NAME AVAIL REFER USED QUOTA RECSIZE REFQUOTA > REFRESERV RESERV VOLBLOCK VOLSIZE > iscsi-pool/log_1_1 33.7G 54K 24.4G - - - > 24.4G none 8K 24.4G > > > (btw, i know the VOLSIZE/USED value of 24.4G derives from the > Sun disk label, because I wrote the label "by hand" using ''format'' > and iSCSI Target code). > > the scsi READ CAPACITY command returns "24.4GB". is the (33GB-24GB) > space used by zfs as metadata? and/or: why wouldn''t the READ-CAPACITY > command return a value that''s a lot closer to 33GB? > > tnx > /andrew > > (I work in Sun''s Sustaining group) > > > On 08/03/09 12:02, Cindy.Swearingen at Sun.COM wrote: > >> Hi Andrew, >> >> The AVAIL column indicates the pool size, not the volsize >> in this example. >> >> In your case, the iscsi-pool/log_1_1 volume is 24 GB in size >> and the remaining pool space is 33.7G. The 33.7G reflects >> your pool space, not your volume size. >> >> The sizing is easier to see if you include the zpool list >> output and a fuller zfs list output. >> >> Cindy >> >> On 08/03/09 10:35, Andrew A. Rutz wrote: >> >>> hi, >>> >>> i''m using a zvol someone else created (and then used as >>> an iSCSI Target, via: "iscsitadm ... -b /dev/zvol ..."). >>> >>> I see that AVAIL has a size of 33GB, yet the VOLSIZE is 24GB ; >>> >>> # zfs list -t volume -o name,avail,used,volsize iscsi-pool/log_1_1 >>> NAME AVAIL USED VOLSIZE >>> iscsi-pool/log_1_1 33.7G 24.4G 24.4G >>> >>> >>> I debugged ''format'', and it received a size of 24GB from Sun''s >>> iSCSI Target implementation. ''format'' did a READ-CAPACITY (scsi) >>> cmd and was returned "24GB". >>> >>> why does 33GB show as AVAIL ? should i be expecting 33GB''s worth >>> of usable disk space? ...or does AVAIL (for some weird reason also) >>> include metadata) ?? >>> >>> # zdb -v iscsi-pool/log_1_1 >>> Dataset iscsi-pool/log_1_1 [ZVOL], ID 117, cr_txg 74, 54.0K, 3 objects >>> >>> Object lvl iblk dblk lsize asize type >>> 0 7 16K 16K 16K 14.0K DMU dnode >>> 1 4 16K 8K 24.4G 38.0K zvol object <<<<<< >>> 2 1 16K 512 512 1K zvol prop >>> >>> >>> thanks >>> /andrew >> >> _______________________________________________ >> zfs-discuss mailing list >> zfs-discuss at opensolaris.org >> http://mail.opensolaris.org/mailman/listinfo/zfs-discuss