Libvirt: Unable to define LVM storage pool
Hello,
I'm trying to define an LVM storage pool for my virtual machines using KVM/libvirt. The configuration looks like this:
<pool type="logical">
<name>vol0</name>
<source>
<device path="/dev/md0"/>
</source>
<target>
<path>/dev/vol0</path>
</target>
</pool>
The problem is, that this LVM group is already active (other vms running using volumes inside this group) and 'virsh pool-start vol0' wants me to disable it. Is there any way to start the pool without "deactivate" the volume group?
virsh pool-start vol0
error: internal error '/sbin/vgchange -an vol0' exited with non-zero status 5 and signal 0: Can't deactivate volume group "vol0" with 14 open logical volume(s)
Further, I'm a bit curious that libvirt might recreate the volume group and therefore deletes all the content during the building process.
Would appreciate any advice
Regards,
Jonas
maahes wrote:
did so now, only now I'm getting a slightly different error: could not find udevd no such file or directory. I checked both grub.cfg's and my mkinitcpio.conf and there's no listing for udevd ....which I've never heard of, so I assumed it was a typo?
For clarification: udev is in the mkinitcpio.
I'm not sure whether I yet have a good intuition for how you have your machine set up, but I suspect you need to include a cryptdevice flag to the kernel in your grub config. The file isn't found because the kernel doesn't know your root directory needs decrypting first.
My setup is an LVM over LUKS over LVM sandwich. To boot into my system, the grub.cfg contains the line:
linux /vmlinuz-linux root=/dev/mapper/cryptvg-root cryptdevice=/dev/mapper/vg-crypt:root rootfstype=ext4 pcie_aspm=force acpi_osi=Linux acpi_backlight=vendor i915.i915_enable_rc6=1 i915.i915_enable_fbc=1 i915.lvds_downclock=1 ro
Now, most of those flags don't have anything to do with your problem, but note the cryptdevice. It tells the kernel it's dealing with an encrypted filesystem sitting in a logical volume called crypt on a volume group called vg. The bit after the colon tells the kernel to associate this encrypted filesystem with /dev/mapper/root.
As for how to fix your system, I'm afraid I still feel a bit fuzzy about how your LVM and encrypted layers relate to each other, whether you have LVM over LUKS, or LUKS over LVM, or something else. Was there a particular how-to that you followed?
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I have a pool of 3x500GB where one the physical drives is having intermittent issues. Currently, there is only one parity Virtual Disk of 300GB Fixed across 3 columns. I want to replace the bad drive with a good one. The old way (pre-2012) was replace the
disk, repair the RAID 5, resync and done. These basic steps are not working.
So far I have added a 4th 500GB drive to the pool. After searching and failing to find a way to move the data non-destructively, I decided to just pull the data cable on the disk I wanted to replace. After refresh/rescan, the disconnected drive shows "lost
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I have several questions:
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using a PS script?
4. Can a deduplicated virtual disk be moved/mirrored/backed up without expanding the data?
Any help is appreciated.Im still fighting with storage pools and need more tests to be done and have a lot of questions my self but ther goes what I understood so far.
You may define physical disks used for virtual disk by Powershell ,
for list of all commands follow this:
http://technet.microsoft.com/en-us/library/hh848705(v=wps.620).aspx ,
specific command defining physical disks to be used on already existing virtual disk:
Example 4: Manually assigning physical disks to a virtual disk
This example gets two physical disks that have already been added to the storage pool and designated as ManualSelect disks,
PhysicalDisk3 and PhysicalDisk4, and assigns them to the virtual disk
UserData.
PS C:\> Add-PhysicalDisk –VirtualDiskFriendlyName UserData –PhysicalDisks (Get-PhysicalDisk -FriendlyName PhysicalDisk3, PhysicalDisk4)
http://technet.microsoft.com/en-us/library/hh848702(v=wps.620).aspx
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Creating multiple storage pools on a 7110
Just received our first 7110 and so far it seems great. We are planning on using this device for database storage (MS SQL Server) and as such wanted to configure 2 storage pools, however through the config UI I cannot figure out how to make that happen. Is is possible on a 7110 to have multiple storage pools carved out of the base device? I've read docs where it appears if we add an additional JBOD we can make that happen but can't find anything related to the base device. If someone could point me in the right direction that would be great.
The 7110 only supports one storage pool and you are not able to add additional storage to the 7110 platform at current release. You are able to create two pools with a 7410. Most of the time you are thinking in terms of older storage where you have to define the raid sets - its a little different with this as ZFS provides the magic. I think if you set it up and start to play you will see the preformance - the 7210 you can also start to add SSD if needed.
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Hi,
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I've created volumes on that disk, NTFS, Thin, Different size.
I create iSCSI VIRTUAL DISKS on those Volumes, same size (my volumes are full)
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The Volume status turn to "Extend failed" with "Error extending volume: Size Not Supported"
Can you help? I need to change my volumes size...
ThxI also could not get my partition to extend using the new Windows Server 2012 interface. Did you try to extend volume from the "computer management", "disk management" console? Get there from Administrator Tools - Computer Management. I
was able to extend my partition only from there. You need to first make sure you have available space on the disk. I had to delete an empty volume first before I was able to extend the partition. Hope this helps. Anthony :)
Thx !!
While in the Computer Management, I realised that my Disk was "Basic" and not "Dynamics", Extending using the Disk Management suggest to switch to Dynamics, and it's now working.
The error in the Server Manager should be "Unable to Extend : Your disk is Basic" or something like.
The Disk is a virtual disk on my Storage Pools.!!! -
Unable to define Radio Button Text field & unable to change column position
Hi,
While designing a screen in Screen Painter, I am unable to define Radio Button Text field as this option is not there in Graphical Element. And also I want to specify the starting position of column of that element different from the default value, but I am unable to define that because the field is non-editable.
Can any one please help me out.
Regards,
KoushikHi,
Please find below the sample program from ABAP docu :
PROGRAM demo_dynpro_input_output.
DATA: input TYPE i,
output TYPE i,
radio1(1) TYPE c, radio2(1) TYPE c, radio3(1) TYPE c,
box1(1) TYPE c, box2(1) TYPE c, box3(1) TYPE c, exit(1) TYPE c.
CALL SCREEN 100.
MODULE init_screen_100 output.
CLEAR input.
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CLEAR: radio2, radio3.
ENDMODULE.
MODULE user_command_0100 input.
output = input.
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box3 = radio3.
IF exit NE space.
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ENDIF.
ENDMODULE.
Here radio1(1) TYPE c is defined within the program but in the element list there are RADIO1 element exist. One is actual radio button and the other is Radio Button Text.
I am not able to create that radio button text using same object name.
Please suggest.
Regards,
Koushik -
Greetings,
I'm having some trouble with my Windows Storage Pool and my VirtualDisk running on a Windows Server 2012 R2 installation. It consists of 8x Western Digital RE-4 2TB drives + 2x Western Digital Black Edition 2TB drives and have been configured in a single-disk
parity setup and the virtual disk is running fixed provisioning (max size) and is formatted with ReFS.
It's been running solid for months besides some awful write-speeds at times, it seems like the write performance running ReFS compared to NTFS is not that good.
I was recommended to add SSD's for journalling in order to boost write-performance. Sadly I seemed to screw up this part, you need to due this through PowerShell and it needs to be done before creating the virtualdisk. I managed to add my SSD to the Storage
Pool and then remove it.
This seem to have caused some awkward issues, I'm not quite sure of why as the virtualdisk is "fixed" so adding the SSD to the Storage Pool shouldn't really do anything, right? But after I did this my virtual disk have been stuck in "Warning:
In Service" and it seems to be stuck? It's been 4-5 days and it's still the same and the performance is currently horrible. Moving 40GB of data off the virtual disk took me about 20 hours or so. Launching files under 1mb of the virtual disk takes several
minutes etc.. It's pretty much useless.
The GUI is not providing any useful information about what's going on. What does "Warning: In Service" actually imply? How am I supposed to know how long this is supposed to take? Running Get-Virtualdisk in PowerShell does not provide any useful
information either. I did try to do a repair through the Server Manager GUI but it goes to about 21% within 2-3 hours but drops back down to 10%. I have had the repair running for days but it wont go past 21% without dropping back down again.
Running repair through PowerShell yields the same results, but if I detach the virtual disk and then try to repair through PowerShell (the GUI wont let me do repair on detached virtual disks) it will just run for a split second and then close.
After doing some "Googeling" I've seen people mentioning that the repair is not able to finish unless I have at least the same amount of free space in the Storage Pool as the largest drive in my Storage Pool is housing so I added a 4TB drive as
due to me running fixed provisioning I had used all the space in the pool but the repair is still not able to go past 21%.
As am running "fixed provisioning" I guess adding a extra drive to the pool doesn't do much difference as it's not available for the virtual disk? So I went ahead and deleted 3 TB of data on the virtual disk so now I've got about 4 TB free space
on the virtual disk so there should be plenty of room for Windows Server 2012 R2 to re-build the parity or whatever it's trying to do but it's still the same, the repair wont move past 21% and the virtual disk is still stuck in "Warning: In Service"
mode and the performance keeps being horrible so taking a backup will take forever at these speeds...
Am I missing something here? All the drives in the pool is working fine. I have verified using various bootable tools so why is this happening and what can I do to get the virtual disk running at full state again? Why doesn't the GUI prompt you with any
kind of usable information?
Best regards, Thomas AndreHi,
Please run chkdsk /f /r command on the virtual disk to have a try. In the meantime, run the following commands in PowerShell to share the output.
get-virtualdisk -friendlyname <name> | get-physicaldisk | fl
get-virtualdisk -friendlyname <name> |fl
Best Regards,
Mandy
Please remember to mark the replies as answers if they help and unmark them if they provide no help. If you have feedback for TechNet Subscriber Support, contact [email protected] -
After upgrading to 8.1 Pro from 8.0 Pro, my Storage Spaces and Storage Pool are all gone.
Under 8.0 I had three 4-terabyte drives set up as a Storage Pool in Storage Spaces. I had five storage-space drives using this pool I had
been using them for months with no problems. After upgrading to 8.1 ( which gave no errors ) the drives no longer exist. Going into "Storage Spaces" in the control panel, I do not see my existing storage pool or storage drives. I'm prompted
to create a new Pool and Storage Spaces. If I click the "Create Pool" it does not list the three drives I used previously as available to add.
Device Manager shows all three drives as present and OK.
Disk Management shows Disks 0,1,2,6. The gap in between 2 and 6 is where the 3,4,5 storage spaces drives were.
Nothing helpful in the event log or the services.
I've downloaded the ReclaiMe Storage Spaces recovery tool and it sees all of my logical drives with a "good" prognosis for recovery. I've not gone down that road yet though because it requires separate physical drives to copy everything to
and they want $299 for the privilege.
Does anyone have any ideas? I'm thinking of doing a fresh 8.1 install to another drive to see if it can see it or reinstalling 8.1 to the existing drive in the hope that it will just suddenly work. Or possibly going back to 8.0.
Thanks for your help!
SteveHi,
“For parity spaces you must backup your data and delete the parity spaces. At this point, you may upgrade or perform a clean install of Windows 8. After the upgrade or clean installation is complete, you may recreate parity spaces and
restore your data.”
I’d like to share the following article with you for reference:
Storage Spaces Frequently Asked Questions
(Pay attention to this part:How do I prepare Storage Spaces for upgrading from the Windows 8 Consumer Preview to Windows 8 Release Preview?)
http://social.technet.microsoft.com/wiki/contents/articles/11382.storage-spaces-frequently-asked-questions-faq.aspx#How_do_I_prepare_Storage_Spaces_for_upgrading_from_the_Windows_8_Consumer_Preview_to_Windows_8_Release_Preview
Regards,
Yolanda
We
are trying to better understand customer views on social support experience, so your participation in this
interview project would be greatly appreciated if you have time.
Thanks for helping make community forums a great place. -
Server 2012 R2 Storage Pool Disk Identification Method
Hi all,
I'm currently using Server 2012 R2 Essentials with a Storage Space consisting of 7 3TB disks. The disks are connected to an LSI MegaRAID controller which does not support JBOD so each disk is configured as a single disk RAID0. The disks are connected to
the controller using SAS Breakout Cables (SATA to SFF-8087).
I am considering moving my server into a new chassis. The new chassis has a SAS Backplane for drive attachment which means I would be re-cabling to use SFF-8087 to SFF-8087 cables instead and in doing so, the channel and port assignment on the LSI MegaRAID
will change.
I know that the LSI card will have no problem identifying the disk as the same disk when it's connected to a different port or channel on the controller, but is the same true for the Storage Space?
How does Storage Spaces track the identity of the individual disks?
Just to be clear, the hardware configuration otherwise will not be changing. Motherboard, CPU, RAID controller etc will all be the same, it will just be moving everything into a new chassis.Hi,
If the disks are still recognized as the same, the storage space should be recognized as well.
You could test to do the replacement and see if the storage pools are being recognized. If not you can still change them back with original devices and storage pools will back to work. Then we may need to find a way to migrate your data. Personally I think
it will work directly.
Note: backup important files is always recommended.
If you have any feedback on our support, please send to [email protected] -
Creation of new storage pool on iomega ix12-300r failed
I have a LenovoEMC ix12-300r (iomega version).
IX12-300r serial number: 2JAA21000A
There is at present one storagepool (SP0) consisting of 8 drives (RAID5).
HDD 1-8 (existing SP0): ST31000520AS CC38
I have aquired 4 new Seagate ST3000DM001 drives as per recommendation on this forum:
https://lenovo-na-en.custhelp.com/app/answers/detail/a_id/33028/kw/ix12%20recommended%20hdd
I want to make a new storage pool with these 4 drives:
HDD9-12 (new HDD and SP1): ST3000DM001-1CH166 CC29
I have used diskpart to clean all 4 drives and the IX12-300r can see the drives just fine.
When I try to make a new storage pool, naming it SP1 as the only storage pool is named SP0, I get an error: "Storage Pool Creation Failed"
Please advise as to how I can get these drives up and running.
Regards
Kristen Thiesen
adena ITI have pulled the 8 hdd from storage pool 0.
Then I rebooted with the 4 new hdd in slot 9 - 12.
Result: http://device IP/manage/restart.html, with the message: Confirmation required. You must authorize overwrite existing data to start using this device. Are you sure you want to overwrite existing data?k [yes] / [no]
I then answer yes four times anticipating that each new drive needs an acceptance, but the dialog just keeps poping up...
Then I shut down the device and repositioned the 4 new drives to slot 1-4 - but the same thing happened...
Any suggestions? -
Win 8.1 Storage Pool not allowing "add drive" nor allow expand capacity
Have one Storage Space within one Storage Pool (Parity mode) containing 4 identical hard drives.
Used for data storage, it appears to be functioning normally
and
has filled 88% of capacity
(ie. 88% x 2/3 of physical capacity (parity mode))
The only other storage on this new PC is an SSD used for OS (win 8.1 pro) and application software.
In "Manage Storage Spaces"
displays this warning message to add drives:
< Warning >
< Low capacity; add 3 drives >
After clicking "add drives", it displays:
"No drives that work with Storage Spaces are available. Make sure that the drives that you want to use are connected.".
However I had connected another two identical hard drives via SATA cables and "Disk Management" displays these two drives available.
in summary:
"Manage Storage Spaces" does not find these drives as available although they show correctly in Disk Management.
btw - I removed the pre-existing partitioning on the 'new' drives so now they show only as "unallocated" in "Disk Management". (I did
likewise before Storage Pool found the 4 original drives)
Perhaps the problem is to increase the total nominal capacity of the Storage Space, before can add more drives?
Microsoft says that the capacity of Storage Pools can be increased but cannot be decreased -
but computer displays no Change "button" by which this can be done. There is supposed to be a "Change" button but that is
not displaying for me. So "Manage Storage Spaces" offer me no option to manage the "size" of the pool.
only five options are displayed:
Create a storage space (ie. from the small amount remaining unused in the Pool)
Add drives (.... as explained already)
Rename pool (only renames the storage space)
Format (ie. re-format and so lose all current data)
Delete (ie. delete the storage space and so lose all current data)
using Google, find nothing bearing on this problem
except the most basic instructions to set up a storage space!
Can you help?
The problem is that the Storage Pool is not displaying a "button" to increase capacity, and when click "add drives" finds no hard drives available.Hi,
I would suggest you launch Device Manager, then expand
Disk drives. Right-click the disk listed as "Disk drive", and select
Uninstall. On the Action menu, click Scan for hardware changes to reinstall the disk.
Please also take a look of this link:
see this part: How do I increase pool capacity?
http://social.technet.microsoft.com/wiki/contents/articles/11382.storage-spaces-frequently-asked-questions-faq.aspx#How_do_I_increase_pool_capacity
According to the link, to extend a parity space, the pool would need the appropriate number of columns available to accommodate the layout of the disk.
Yolanda Zhu
TechNet Community Support -
2012 New Cluster Adding A Storage Pool fails with Error Code 0x8007139F
Trying to setup a brand new cluster (first node) on Server 2012. Hardware passes cluster validation tests and consists of a dell 2950 with an MD1000 JBOD enclosure configured with a bunch of 7.2K RPM SAS and 15k SAS Drives. There is no RAID card or any other
storage fabric, just a SAS adapter and an external enclosure.
I can create a regular storage pool just fine and access it with no issues on the same box when I don't add it to the cluster. However when I try to add it to the cluster I keep getting these errors on adding a disk:
Error Code: 0x8007139F if I try to add a disk (The group or resource is not in the correct state to perform the requested operation)
When adding the Pool I get this error:
Error Code 0x80070016 The Device Does not recognize the command
Full Error on adding the pool
Cluster resource 'Cluster Pool 1' of type 'Storage Pool' in clustered role 'b645f6ed-38e4-11e2-93f4-001517b8960b' failed. The error code was '0x16' ('The device does not recognize the command.').
Based on the failure policies for the resource and role, the cluster service may try to bring the resource online on this node or move the group to another node of the cluster and then restart it. Check the resource and group state using Failover Cluster
Manager or the Get-ClusterResource Windows PowerShell cmdlet.
if I try to just add the raw disks to the storage -- without using a pool or anything - almost every one of them but one fails with incorrect function except for one (a 7.2K RPM SAS drive). I cannot see any difference between it and the other disks. Any
ideas? The error codes aren't anything helpful. I would imagine there's something in the drive configuration or hardware I am missing here I just don't know what considering the validation is passing and I am meeting the listed prerequisites.
If I can provide any more details that would assist please let me know. Kind of at a loss here.Hi,
You mentioned you use Dell MD 1000 as storage, Dell MD 1000 is Direct Attached Storage (DAS)
Windows Server cluster do support DAS storage, Failover clusters include improvements to the way the cluster communicates with storage, improving the performance of a storage area network (SAN) or direct attached storage (DAS).
But the Raid controller PERC 5/6 in MD 1000 may not support cluster technology. I did find its official article, but I found its next generation MD 1200 use Raid controller PERC H 800 is still not support cluster technology.
You may contact Dell to check that.
For more information please refer to following MS articles:
Technical Guidebook for PowerVault MD1200 and MD 1220
http://www.dell.com/downloads/global/products/pvaul/en/storage-powervault-md12x0-technical-guidebook.pdf
Dell™ PERC 6/i, PERC 6/E and CERC 6/I User’s Guide
http://support.dell.com/support/edocs/storage/RAID/PERC6/en/PDF/en_ug.pdf
Hope this helps!
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Slow performance Storage pool.
We also encounter performance problems with storage pools.
The RC is somewhat faster than the CP version.
Hardware: Intel S1200BT (test) motherboard with LSI 9200-8e SAS 6Gb/s HBA connected to 12 ST91000640SS disks. Heavy problems with “Bursts”.
Using the ARC 1320IX-16 HBA card is somewhat faster and looks more stable (less bursts).
Inserting an ARC 1882X RAID card increases speed with a factor 5 – 10.
Hence hardware RAID on the same hardware is 5 – 10 times faster!
We noticed that the “Recourse Monitor” becomes unstable (irresponsive) while testing.
There are no heavy processor loads while testing.
JanV.
JanVBased on some testing, I have several new pieces of information on this issue.
1. Performance limited by controller configuration.
First, I tracked down the underlying root cause of the performance problems I've been having. Two of my controller cards are RAIDCore PCI-X controllers, which I am using for 16x SATA connections. These have fantastic performance for physical disks
that are initialized with RAIDCore structures (so they can be used in arrays, or even as JBOD). They also support non-initialized disks in "Legacy" mode, which is what I've been using to pass-through the entire physical disk to SS. But for some reason, occasionally
(but not always) the performance on Server 2012 in Legacy mode is terrible - 8MB/sec read and write per disk. So this was not directly a SS issue.
So given my SS pools were built on top of disks, some of which were on the RAIDCore controllers in Legacy mode, on the prior configuration the performance of virtual disks was limited by some of the underlying disks having this poor performance. This may
also have caused the unresponsiveness the entire machine, if the Legacy mode operation had interrupt problems. So the first lesson is - check the entire physical disk stack, under the configuration you are using for SS first.
My solution is to use all RAIDCore-attached disks with the RAIDCore structures in place, and so the performance is more like 100MB/sec read and write per disk. The problems with this are (a) a limit of 8 arrays/JBOD groups to be presented to the OS (for
16 disks across two controllers, and (b) loss of a little capacity to RAIDCore structures.
However, the other advantage is the ability to group disks as JBOD or RAID0 before presenting them to SS, which provides better performance and efficiency due to limitations in SS.
Unfortunately, this goes against advice at http://social.technet.microsoft.com/wiki/contents/articles/11382.storage-spaces-frequently-asked-questions-faq.aspx,
which says "RAID adapters, if used, must be in non-RAID mode with all RAID functionality disabled.". But it seems necessary for performance, at least on RAIDCore controllers.
2. SS/Virtual disk performance guidelines. Based on testing different configurations, I have the following suggestions for parity virtual disks:
(a) Use disks in SS pools in multiples of 8 disks. SS has a maximum of 8 columns for parity virtual disks. But it will use all disks in the pool to create the virtual disk. So if you have 14 disks in the pool, it will use all 14
disks with a rotating parity, but still with 8 columns (1 parity slab per 7 data slabs). Then, and unexpectedly, the write performance of this is a little worse than if you were just to use 8 disks. Also, the efficiency of being able to fully use different
sized disks is much higher with multiples of 8 disks in the pool.
I have 32 underlying disks but a maximum of 28 disks available to the OS (due to the 8 array limit for RAIDCore). But my best configuration for performance and efficiency is when using 24 disks in the pool.
(b) Use disks as similar sized as possible in the SS pool.
This is about the efficiency of being able to use all the space available. SS can use different sized disks with reasonable efficiency, but it can't fully use the last hundred GB of the pool with 8 columns - if there are different sized disks and there
are not a multiple of 8 disks in the pool. You can create a second virtual disk with fewer columns to soak up this remaining space. However, my solution to this has been to put my smaller disks on the RAIDCore controller, and group them as RAID0 (for equal
sized) or JBOD (for different sized) before presenting them to SS.
It would be better if SS could do this itself rather than needing a RAID controller to do this. e.g. you have 6x 2TB and 4x 1TB disks in the pool. Right now, SS will stripe 8 columns across all 10 disks (for the first 10TB /8*7), then 8 columns across 6
disks (for the remaining 6TB /8*7). But it would be higher performance and a more efficient use of space to stripe 8 columns across 8 disk groups, configured as 6x 2TB and 2x (1TB + 1TB JBOD).
(c) For maximum performance, use Windows to stripe different virtual disks across different pools of 8 disks each.
On my hardware, each SS parity virtual disk appears to be limited to 490MB/sec reads (70MB/sec/disk, up to 7 disks with 8 columns) and usually only 55MB/sec writes (regardless of the number of disks). If I use more disks - e.g. 16 disks, this limit is
still in place. But you can create two separate pools of 8 disks, create a virtual disk in each pool, and stripe them together in Disk Management. This then doubles the read and write performance to 980MB/sec read and 110MB/sec write.
It is a shame that SS does not parallelize the virtual disk access across multiple 8-column groups that are on different physical disks, and that you need work around this by striping virtual disks together. Effectively you are creating a RAID50 - a Windows
RAID0 of SS RAID5 disks. It would be better if SS could natively create and use a RAID50 for performance. There doesn't seem like any advantage not to do this, as with the 8 column limit SS is using 2/16 of the available disk space for parity anyhow.
You may pay a space efficiency penalty if you have unequal sized disks by going the striping route. SS's layout algorithm seems optimized for space efficiency, not performance. Though it would be even more efficient to have dynamic striping / variable column
width (like ZFS) on a single virtual disk, to fully be able to use the space at the end of the disks.
(d) Journal does not seem to add much performance. I tried a 14-disk configuration, both with and without dedicated journal disks. Read speed was unaffected (as expected), but write speed only increased slightly (from 48MB/sec to
54MB/sec). This was the same as what I got with a balanced 8-disk configuration. It may be that dedicated journal disks have more advantages under random writes. I am primarily interested in sequential read and write performance.
Also, the journal only seems to be used if it in on the pool before the virtual disk is created. It doesn't seem that journal disks are used for existing virtual disks if added to the pool after the virtual disk is created.
Final configuration
For my configuration, I have now configured my 32 underlying disks over 5 controllers (15 over 2x PCI-X RAIDCore BC4852, 13 over 2x PCIe Supermicro AOC-SASLP-MV8, and 4 over motherboard SATA), as 24 disks presented to Windows. Some are grouped on my RAIDCore
card to get as close as possible to 1TB disks, given various limitations. I am optimizing for space efficiency and sequential write speed, which are the effective limits for use as a network file share.
So I have: 5x 1TB, 5x (500GB+500GB RAID0), (640GB+250GB JBOD), (3x250GB RAID0), and 12x 500GB. This gets me 366MB/sec reads (note - for some reason, this is worse than the 490MB/sec when just using 8 of disks in a virtual disk) and 76MB/sec write (better
than 55MB/sec on a 8-disk group). On space efficiency, I'm able to use all but 29GB in the pool in a single 14,266GB parity virtual disk.
I hope these results are interesting and helpful to others! -
Unable to enter Manage Storage in Icloud backup and storage
I'm unable to enter Manage Storage in Icloud backup and storage. I'm clicking on Manage Storage and nothing happens. I am out of storage and I cant menage it. I have IOS 5.0.1
There is a unbelievably simple "solution" to this problem (not getting in to manage storage, only spinning wheel).
All you have to do is click "backup now" at the bottom and immediately as it is calculating estimated time for backup you click "manage storage" and VOILA! You´re in. Believe me it works, done it on 2 phones this evening. One 4s on iOS7 and one 5 on iOS6.1.3 -
Unable to buy additional storage using my iTunes card?
Unable to buy additional storage using my iTunes card credit?
Storage at iCloud doesn't make more room on your iPad.
Extra storage (over the base 5 GB's) would only be useful if you were backing up your iPad data to iCloud. You can already backup to your computer using iTunes. Restoring is much faster than iCloud. -
Adding drives to storage pool with same unique id
i have seen a lot of discussion about using storage pools with raid controllers that reporting the same unique id across multiple drives.
I am yet to find a solution to my problem is that i can't add 2 drives to storage pool because they share the same unique id. Is there a way i can get around this?
Thanks brendonThanks for your reply,
However, Storage spaces uses the uniqueid that the raid / sata controller reports for the drive. in my case this is the output from powershell
PS C:\Users\tfs> get-physicaldisk | ft FriendlyName, uniqueid
FriendlyName uniqueid
PhysicalDisk1 2039374232333633
PhysicalDisk2 2039374232333633
PhysicalDisk10 SCSI\Disk&Ven_Hitachi&Prod_HDS722020ALA330\4&37df755d&0&...
PhysicalDisk8 SCSI\Disk&Ven_WDC&Prod_WD10EACS-00D6B0\4&37df755d&0&0300...
PhysicalDisk6 SCSI\Disk&Ven_WDC&Prod_WD10EADS-00M2B0\4&37df755d&0&0100...
PhysicalDisk7 SCSI\Disk&Ven_&Prod_ST2000DL003-9VT1\4&37df755d&0&020000...
PhysicalDisk0 2039374232333633
PhysicalDisk4 SCSI\Disk&Ven_&Prod_ST3000DM001-9YN1\5&10a0425f&0&010000...
PhysicalDisk3 SCSI\Disk&Ven_Hitachi&Prod_HDS723030ALA640\5&10a0425f&0&...
PhysicalDisk9 SCSI\Disk&Ven_&Prod_ST31500341AS\4&37df755d&0&040000:sho...
PhysicalDisk5 SCSI\Disk&Ven_WDC&Prod_WD1001FALS-00J7B\4&37df755d&0&000...
as you notice i have 3 drives with the same uniqueid. This i cannot change and this is what i am looking for a workaround for.
If you have any thoughts that would be great.
Thanks in advance
Brendon
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