Hi all,
The netapp documentation is very short on a few things regarding Hyper-V and alignment. (tr-3702)
Questions:
1. Do we need to set the default allocation unit size when formatting the disk to 4096 or leave at default
2. I never see any of the blocks in anything other than histo.0 but there are partials.... do these partials mean that there was say 5020k of data to write and that it just didn’t have enough data to fill the block or that its misaligned?
3. If misaligned what else can be done?
Take this situation.
Server 2008 R2 x64 Hyper-V
Were using a Fixed disk on a volume with 100% fraction reservation and 0% reservation on the lun. Both lun and initiators are hyper-v type (the host os is localdisk). After we initialize the disk from the Host we then align the disk "align=32" then we format the disk changing the default allocation size to 4096 (don’t know if we have to change it from default or not it’s not mentioned in the documentation and the results didn’t seem to change with either of them) . Then we create the vm using a fixed disk (40gb shows up as 39 in diskpart)... were installing srv 2003... so we pop in the iso for 2008 r2 x64 to get diskpart (from the repair section) and align the child vm to "align=32".... and when installing the os we get the stats below.... is this aligned or not. Again in the documentation it doesn’t mention the partial blocks area only whether or not it’s on the same histogram, which it always is but there are some partials.
priv set diag; stats show lun:/vol/TESTVOL/TESTQTREE/TESTHYPERVCDRIVE-W-Lva4Tje4g-; priv set admin
Warning: These diagnostic commands are for use by IBM
personnel only.
lun:/vol/TESTVOL/TESTQTREE/TESTHYPERVCDRIVE-W-Lva4Tje4g-:display_name:/vol/TESTVOL/TESTQTREE/TESTHYPERVCDRIVE
lun:/vol/TESTVOL/TESTQTREE/TESTHYPERVCDRIVE-W-Lva4Tje4g-:read_ops:3/s
lun:/vol/TESTVOL/TESTQTREE/TESTHYPERVCDRIVE-W-Lva4Tje4g-:write_ops:24/s
lun:/vol/TESTVOL/TESTQTREE/TESTHYPERVCDRIVE-W-Lva4Tje4g-:other_ops:0/s
lun:/vol/TESTVOL/TESTQTREE/TESTHYPERVCDRIVE-W-Lva4Tje4g-:read_data:66048b/s
lun:/vol/TESTVOL/TESTQTREE/TESTHYPERVCDRIVE-W-Lva4Tje4g-:write_data:1236480b/s
lun:/vol/TESTVOL/TESTQTREE/TESTHYPERVCDRIVE-W-Lva4Tje4g-:queue_full:0/s
lun:/vol/TESTVOL/TESTQTREE/TESTHYPERVCDRIVE-W-Lva4Tje4g-:avg_latency:0.03ms
lun:/vol/TESTVOL/TESTQTREE/TESTHYPERVCDRIVE-W-Lva4Tje4g-:total_ops:27/s
lun:/vol/TESTVOL/TESTQTREE/TESTHYPERVCDRIVE-W-Lva4Tje4g-:scsi_partner_ops:0/s
lun:/vol/TESTVOL/TESTQTREE/TESTHYPERVCDRIVE-W-Lva4Tje4g-:scsi_partner_data:0b/s
lun:/vol/TESTVOL/TESTQTREE/TESTHYPERVCDRIVE-W-Lva4Tje4g-:read_align_histo.0:66%
lun:/vol/TESTVOL/TESTQTREE/TESTHYPERVCDRIVE-W-Lva4Tje4g-:read_align_histo.1:0%
lun:/vol/TESTVOL/TESTQTREE/TESTHYPERVCDRIVE-W-Lva4Tje4g-:read_align_histo.2:0%
lun:/vol/TESTVOL/TESTQTREE/TESTHYPERVCDRIVE-W-Lva4Tje4g-:read_align_histo.3:0%
lun:/vol/TESTVOL/TESTQTREE/TESTHYPERVCDRIVE-W-Lva4Tje4g-:read_align_histo.4:0%
lun:/vol/TESTVOL/TESTQTREE/TESTHYPERVCDRIVE-W-Lva4Tje4g-:read_align_histo.5:0%
lun:/vol/TESTVOL/TESTQTREE/TESTHYPERVCDRIVE-W-Lva4Tje4g-:read_align_histo.6:0%
lun:/vol/TESTVOL/TESTQTREE/TESTHYPERVCDRIVE-W-Lva4Tje4g-:read_align_histo.7:0%
lun:/vol/TESTVOL/TESTQTREE/TESTHYPERVCDRIVE-W-Lva4Tje4g-:write_align_histo.0:83%
lun:/vol/TESTVOL/TESTQTREE/TESTHYPERVCDRIVE-W-Lva4Tje4g-:write_align_histo.1:0%
lun:/vol/TESTVOL/TESTQTREE/TESTHYPERVCDRIVE-W-Lva4Tje4g-:write_align_histo.2:0%
lun:/vol/TESTVOL/TESTQTREE/TESTHYPERVCDRIVE-W-Lva4Tje4g-:write_align_histo.3:0%
lun:/vol/TESTVOL/TESTQTREE/TESTHYPERVCDRIVE-W-Lva4Tje4g-:write_align_histo.4:0%
lun:/vol/TESTVOL/TESTQTREE/TESTHYPERVCDRIVE-W-Lva4Tje4g-:write_align_histo.5:0%
lun:/vol/TESTVOL/TESTQTREE/TESTHYPERVCDRIVE-W-Lva4Tje4g-:write_align_histo.6:0%
lun:/vol/TESTVOL/TESTQTREE/TESTHYPERVCDRIVE-W-Lva4Tje4g-:write_align_histo.7:0%
lun:/vol/TESTVOL/TESTQTREE/TESTHYPERVCDRIVE-W-Lva4Tje4g-:read_partial_blocks:33%
lun:/vol/TESTVOL/TESTQTREE/TESTHYPERVCDRIVE-W-Lva4Tje4g-:write_partial_blocks:16%