ASM Volumes on thin-provisioned SAN dirtying all blocks

Hi there, sorry for the x-post from database-general but it was suggested that I do so. Anyhow, we've got 11g (11.1.0.7 with the 6851110 ASM patch recently applied) running on OEL 5 x86_64, with ASM connected to a raw, thin-provisioned ISCSI volume partitioned for DATA and FRA, and in every case where we do so, the SAN device reports within a few weeks that the whole volume has been allocated even though the DB (configured with autoextend on) is only holding about one tenth of the amount of available space on the device. What this means in systems terms is that somehow ASM is marking writes to nearly every block on the drive if only momentarily.
In the original thread, there was speculation that a process of indexing AUs has led to the dirtying of the whole volume, but this would make more sense if the whole disk had been allocated immediately rather than over the course of a few weeks. My question is: what else could account for this behavior, and what steps can I take to help ensure that ASM behaves correctly in a thin-provisioned volume? (by "correctly" I mean writes contiguous blocks of data and doesn't dirty the whole thing)
Thanks!

Hi,
recently i had some time and did some tests with thin provisioning and ASM.
I used storage based on Opensolaris with ZFS thin provisioning against a 11g R2 database with 11g R2 ASM running on Windows. I created two LUNs and exported the LUNs via iSCSI. On the ASM side i formed a single disk group with external redundancy of the two LUNs presented and created one big file tablespace with approx 15 GB total size.
The storage systems shows the LUNs as follows:
NAME                       PROPERTY       VALUE    SOURCE
pool1/iscsi-racwin-temp05 volsize        15G      local
pool1/iscsi-racwin-temp05 usedbydataset 7.45G    -
pool1/iscsi-racwin-temp06 volsize        15G      local
pool1/iscsi-racwin-temp06 usedbydataset 7.45G    -You can see: 15 GB total size reported while 7.45 GB are allocated. Thats pretty normal due to the data file created in the disk group.
During the night i ran a script which imported a schema and dropped it afterwards. The steps were repeated infinitely.
After more than 24 hours the thin provisioned disks look like this:
NAME                       PROPERTY       VALUE    SOURCE
pool1/iscsi-racwin-temp05 volsize        15G      local
pool1/iscsi-racwin-temp05 usedbydataset 7.47G    -
pool1/iscsi-racwin-temp06 volsize        15G      local
pool1/iscsi-racwin-temp06 usedbydataset 7.47G    -As you can see there is a extremely small growth in size (from 7.45 GB to 7.47 GB). I observed this growth shortly after starting the very first import. Subsequent imports did not increased the actual allocated volume size.
So if we exclude the storage as a source for problems there might be the fact that 11g R1 ASM behaves different than 11g R2 ASM. I have not yet tested this...
Ronny Egner
My Blog: http://blog.ronnyegner-consulting.de

Similar Messages

ASM Volumes on thin-provisioned ISCSI dirtying whole volumes

Hi, we've got some EBS test instances going and are testing auto-extend (in reasonable chunks) on a thin-provisioned ISCSI volume for the 11g database tier. Something doesn't seem right though: typically I see about 55GB in use by datafiles but about 95% of the thin-provisioned volume is marked dirty.
Obviously, this sort of negates the point of using thin provisioning at all, but I can't help but think there's something else at work here. Does anyone have experience with this situation and if so what parameters can be set to make what we're trying to do actually work right?

Billy, thank you for the helpful reply. In this case, none of that is news to me - we wear a lot of hats where I work and in this case I not only put together the systems the ASM instance is running on, but the ASM instance itself (DB is at 11.1.0.7 with the 6851110 ASM patch recently applied). System is OEL 5 x86_64, the ISCSI volume is thin-provisioned, no filesystem ever written to it, raw disk other than a partition table, holds DATA and FRA, configured with autoextend on.
What I'm trying to get at here is why a 500GB volume which is holding only about 55GB of data would have almost all its blocks marked dirty - as far as the filer is concerned, something has touched nearly every block on the volume at one point or another. Now if I'd written a 500GB datafile to it - which as you say is pointless where ASM is concerned - I'd understand how the blocks got dirtied, but in this case that never happened - it's somewhere in the way ASM behaves (as far as I can see now anyway) that has caused the data to be written all over the physical blocks on the drive, even if only momentarily.
So getting back to my original question, is there a way in ASM to ensure that writes are done in a contiguous fashion so that the apparent disk usage (from the SAN point of view) more closely matches the actual amount of data stored? I'm not seeking a 1:1 relationship here, but we're close to 1:10, and I think that's only because that's how big I sized the volume in the first place. As far as it being ISCSI, the only relevance (and the whole point of my question) is that it's how I happened to attach the volume, which was intended to be thin-provisioned and only allocate space when it's needed. If I'd made the volume 250GB (and I can test this theory if need be), it would likely dirty 250GB of blocks and still store the same 55GB of data. My hope is that there's a way to get ASM to play nicer on thin-provisoned volumes than what I'm currently seeing.
Thanks again.

ISCSI and ZFS Thin Provisioning Sparse Volumes - constraints?

Hello,
I am running an iSCSI target using COMSTAR.
I activated Time Slider (Snapshot feature) for all pools.
Now I want to set up an iSCSI target using thin provisioning, storing the data in a file system rather than a file.
Is there any official documentation about thin p.?
All I found was
http://www.cuddletech.com/blog/pivot/entry.php?id=729
http://www.c0t0d0s0.org/archives/4222-Less-known-Solaris-Features-iSCSI-Part-4-Alternative-backing-stores.html
Are there any problems to be expected about the snapshots?
How would I set up a 100 GByte iSCSI target with mentioned thin p.?
Thanks
n00b

To create a thin provisioned volume:
zfs create -V <SIZE> -s path/to/volume
Where <SIZE> is the capacity of the volume and path/to/volume is the ZFS path and volume name.
To create a COMSTAR target:
stmfadm create-lu /dev/zvol/rdsk/path/to/volume
You'll get a LU ID, which you can then use to create a view, optionally with target and host groups to limit access.
-Nick

Need for multiple ASM disk groups on a SAN with RAID5??

Hello all,
I've successfully installed clusterware, and ASM on a 5 node system. I'm trying to use asmca (11Gr2 on RHEL5)....to configure the disk groups.
I have a SAN, which actually was previously used for a 10G ASM RAC setup...so, reusing the candidate volumes that ASM has found.
I had noticed on the previous incarnation....that several disk groups had been created, for example:
ASMCMD> ls
DATADG/
INDEXDG/
LOGDG1/
LOGDG2/
LOGDG3/
LOGDG4/
RECOVERYDG/
Now....this is all on a SAN....which basically has two pools of drives set up each in a RAID5 configuration. Pool 1 contains ASM volumes named ASM1 - ASM32. Each of these logical volumes is about 65 GB.
Pool #2...has ASM33 - ASM48 volumes....each of which is about 16GB in size.
I used ASM33 from pool#2...by itself to contain my cluster voting disk and OCR.
My question is....with this type setup...would doing so many disk groups as listed above really do any good for performance? I was thinking with all of this on a SAN, which logical volumes on top of a couple sets of RAID5 disks...the divisions on the disk group level with external redundancy would do anything?
I was thinking of starting with about half of the ASM1-ASM31 'disks'...to create one large DATADG disk group, which would house all of the database instances data, indexes....etc. I'd keep the remaining large candidate disks as needed for later growth.
I was going to start with the pool of the smaller disks (except the 1 already dedicated to cluster needs) to basically serve as a decently sized RECOVERYDG...to house logs, flashback area...etc. It appears this pool is separate from pool #1...so, possibly some speed benefits there.
But really...is there any need to separate the diskgroups, based on a SAN with two pools of RAID5 logical volumes?
If so, can someone give me some ideas why...links on this info...etc.
Thank you in advance,
cayenne

The best practice is to use 2 disk groups, one for data and the other for the flash/fast recovery area. There really is no need to have a disk group for each type of file, in fact the more disks in a disk group (to a point I've seen) the better for performance and space management. However, there are times when multiple disk groups are appropriate (not saying this is one of them only FYI), such as backup/recovery and life cycle management. Typically you will still get benefit from double stripping, i.e. having a SAN with RAID groups presenting multiple LUNs to ASM, and then having ASM use those LUNs in disk groups. I saw this in my own testing. Start off with a minimum of 4 LUNs per disk group, and add in pairs as this will provide optimal performance (at least it did in my testing). You should also have a set of standard LUN sizes to present to ASM so things are consistent across your enterprise, the sizing is typically done based on your database size. For example:
300GB LUN: database > 10TB
150GB LUN: database 1TB to 10 TB
50GB LUN: database < 1TB
As databases grow beyond the threshold the larger LUNs are swapped in and the previous ones are swapped out. With thin provisioning it is a little different since you only need to resize the ASM LUNs. I'd also recommend having at least 2 of each standard sized LUNs ready to go in case you need space in an emergency. Even with capacity management you never know when something just consumes space too quickly.
ASM is all about space savings, performance, and management :-).
Hope this helps.

Do I need to extend the OS disk if my Datastore is thin provisioned?

I noticed on my windows server (VM) that one of the disk drives was getting low. This was showing 22gb free from the OS. (Windows 2008 R2) It is functioning as the file storage and print server. So, I extended the SAN LUN by 100gb, extended the vCenter Datastore by the same amount and now it's showing in vCenter that I have an extra 100gb of space. On the OS, it's still showing 22gb free. I know that if I go into the VM and edit the properties of the disk drive, and add up to 100gb of space, then on the OS, in this case Windows I can go into disk management and extend the volume I will see the additional space. My question, Do I need to do this if my Datastore is thin provisioned? Will it not grow if needed? or am I getting the OS and VMware confused as to how it functions?

You will need increase the size of virtual disk on the properties of virtual machine to the desired size and after this, if Windows, go to disk management (or diskpart) and extend the disk.
And about the thin provisioning concept, you're confused and I recommend you read this article: Using thin provisioned disks with virtual machines (1005418)

Whether Hyper-V 2012 will support Thin provisioning ?

Hi All,
I am installing windows server 2012 in Hyper V as a VM using iso images.... While creating new virtual machine in Hyper-V I am not able to see any options like "Thin Provisioning"... In Hyper V how thin provisioning will
work and how to enable it?
I install one Server 2012 in Hyper V--> It display harddisk type as "xxxx.vhdx"
Note:In Vmware the thin provisioning option is available while creating virtual machines.
Thanks,
Rajarajan.D

Hello,
I hope you have a great day.
Creating the VHDX file as dynamically expanding, is the VMware equivalent to thin provisioning.
Example: Create dynamically vhdx with size of 100 GB and install Server 2012 OS. The Guest OS will see drive capacity as 100GB however the actual vhdx file would only consume about 15 - 30GB physical hard disk space depending on the features/roles you
install in the OS.
Creating a 100GB Fixed VHDX would consume 100GB of physical hard disk space.

Changing devices for ASM Volumes

Hi,
I have a two node RAC Cluster Setup 10gR2.
I created the ASM Volumes for the database,during the configuration, by the commands
# /etc/init.d/oracleasm createdisk VOL1 /dev/sdb2
I have three Volumes made of /devsdb2, /dev/sdb3 and /dev/sdb4.
Is there a way I can change the devices to /dev/sdd2,/dev/sdd3 and /dev/sdd4 for the ASM Volumes.

Hey all,
Thanx you all for your support.
It worked. The ownership and permissions are not getting reverted back.
But seriously, the rc.local file is not in */etc/init.d/*
It is in */etc*
Infact, I have created a file rc.local in */etc/init.d/*, made the entries, and restarted the system, but of no use.
Then I found the rc.local file in */etc*, made the changes and tested by restarting the system, and it worked.
Thank you all guys. gr8 job..
Thanx again ...
Cheers,
ORA_SRI

Thin provisioning?

Hi All,
I am working on a deployment project Exchange 2013, We have planned to deploy exchange 2013 on VMware platform. Could some one share your experience Exchange 2013 with VMware . I have already gone trough the VMware recommendations but i am looking for some
one with practical experience that would be really help full for me to accomplish this task successfully.
First Question : Can we use thin provisioning for Database and logs?
Second Question : what type of disk we need to use for DB & Logs (RDM or VMFS)? I am beginner to vmware sorry if i have asked any wrong question here :-)
Third Question : How to Size the processor for exchange 2013 with MSCalc? I have followed the below article for MScalc still have some doubts on Processor calculation. :-)
http://blogs.technet.com/b/exchange/archive/2009/11/09/3408737.aspx
Here is the server details, could some one help me with the Processor part, I appreciate your response.
Phycial 4 sockets, 32 cores in total, 256 GB of RAM
SPECint®_rate2006 = 1130
Regards, Balgates

Hi Balgates,
In addition to the above suggestions, I would like to clarify that the megacycle guidance in Exchange 2013 leverages a new server baseline, therefore, you can't directly compare the output from the Exchange 2010 calculator with Exchange 2013 calculator.
For more information about it, here is a blog for your reference.
Sizing Exchange 2013 Deployments
http://blogs.technet.com/b/exchange/archive/2013/05/06/ask-the-perf-guy-sizing-exchange-2013-deployments.aspx
Hope this can be helpful to you.
Best regards,
Amy Wang
TechNet Community Support

So in the last few days I've noticed that pressing my volume change keys actually isn't changing the volume on my macbook pro at all. When I press the volume up or down keys, it makes the recognisable pop sound but stays at the same volume while the squar

So in the last few days I’ve noticed that pressing my volume change keys actually isn’t changing the volume on my macbook pro at all. When I press the volume up or down keys, it makes the recognisable pop sound but stays at the same volume while the squares go up or down. I mute it but my computer still makes sound. It’s the same with the volume control up the top of the screen, too. I slide it up and down and it doesn’t change the volume at all. The only way I can change the volume is with my speakers or the program I’m in (iTunes, VLC etc). I restarted and it seems to be okay then I go to change it a couple minutes later and it’s back to not working again.
I’ve checked my settings- the “use all F1, F2, etc. keys as standard fuction keys” is not switched on, and I have tried a suggestion of moving the com.apple.systempreferences.plist file out of the library and onto the desktop and restarting and neither of those seem to make any difference whatsoever. I’ve tried to find online forums but the only suggestions I found were those two and they didn’t work.
I’m just annoyed because I usually have the worst luck with technology but my macbook had been going strong and I got it because of the apparent lack of things that could go wrong, but of course even if there is one thing that could go wrong it will happen to me.
Please help!

You migh give resetting your NVRAM a try:
http://support.apple.com/kb/ht1379

Why is the Lumia Icon's ringtone lower than when previewing the ringtone in settings/system/ringtone sounds? (The volume is set at 30 in all cases.)

Why is the Lumia Icon's (929) ringtone lower than when previewing the ringtone in settings/system/ringtone+sounds? (The volume is set at 30 in all cases.)

Hello Lena,
Yes, tried all those things.
After going back and forth with Verizon's "tier 2" technical support over the last 2 days, a chat session with Nokia, no call-backs-as-promised by your technicians, then having them reinstall the phone's software -that didn't fix the problem. So they are sending me a re-manufactured replacement phone. But not a NEW ONE, because I didn't realize the problem within 14 days. You see at first, I just figured the phone had lousy volume, until I was previewing ringtones when setting the alarm clock. The phone is about one and a half months old. I have expressed my desire that a NEW phone be sent, but NO says Verizon.
I've spent enough time, in good faith, Verizon would solve this matter, but in the process of their re-installing the software they've screwed up Backup Assistant.
Thanks.

How can I fix my iphone's sound I plugged it in to my radio and the sound came out fine but when I took it out the volume bar dissapered and ever seince all it says volume not available, but it work with headphones in. What can I do to fix it?

How can I fix my iphone's sound I plugged it in to my radio and the sound came out fine but when I took it out the volume bar dissapered and ever seince all it says volume not available, but it work with headphones in. What can I do to fix it?

Try reset all settings.
Settings > General > Reset > Reset all settings. It won't delete any data.

The volume icon stays on the screen all of the time

The volume icon stays on the screen all of the time and the volume does not work.any suggestions?

Try a restart - hold the Home and Sleep buttons for arund 7-8 seconds until the Apple logo appears

How do I get the volume to be the same on all songs in itunes?

how do I get the volume to be the same on all my songs in i
tunes?

maybe the check box Sound Check in iTunes > Preferences > Playback Preferences
will help?

Hi just updated to ios7 Speaker make No sound in music player Volume slider is not functioning at all , it's grey Ringtones works fine. I have apple tv in my local network so in ios 7 music player i switched to play through airplay And back to iphone -

Hi just updated to ios7
Speaker make No sound in music player
Volume slider is not functioning at all , it's grey
Ringtones works fine.
I have apple tv in my local network so in ios 7 music player i switched to play through airplay
And back to iphone - no sound
Also tried another music player same **** - plays no sound
iPhone 4S, iOS 7

Hello there, vishnu cs.
The following Knowledge Base article provides some great information for troubleshooting your issue:
iPhone: No sound or distorted sound from speaker
http://support.apple.com/kb/ts5180
Thanks for reaching out to Apple Support Communities.
Cheers,
Pedro.

Disable every single web fonts in adobe muse and prevent it from loading open-sans:n3:all.js

I'm using Adobe Muse 2014.2 to build a Chinese site. The audience of the site is mainly people in mainland china, and I'm using a server from Hong Kong. Recently I just tested the site, however, it was loading extremely slow. In the end I found out that the cause of the slow loading was due to a file called "open-sans:n3:all.js" that was loaded from adobe webfonts.
Because a lot of sites are blocked in China, I think that Adobe Web Fonts (or typekit) is also blocked thus can't be loaded properly, causing the entire site to slow down.
Is there a way to disable all the webfonts in Muse and to prevent my site from loading this file?
Or is there a way I can host this file on my own server?
Thanks in advance.

This was a snapshot that my friend in China sent to me. You can see that the open-sans:n3:all.js is taking extremely long to load.
Yet the funny thing is that I did not use any web fonts in my site. However Muse is still adding it in the code for some reason.

ASM Volumes on thin-provisioned SAN dirtying all blocks

Similar Messages

Maybe you are looking for