This is R*acer,
I’ve been stuck in a very bad situation and got so confused.
I’m running Oracle 11gR2 on Windows Server 2008 64-bit. We’ve run standalone ASM for our database. The storage which we are using has a reclamation tool but it will only detect the drives with a specific drive letter, whereas to create ASM, we need to give RAW disks. After I’ve investigated, I’ve realized that there is a tool which is known as ASM Reclamation Utility (ASRU). This utility has been created with the cooperation of Oracle team and 3PAR storage team. This tool is exactly the thing which I need. What is happening now in my server is that as much as the database grows, the storage will increase the used space but whenever we delete even a huge amount of database, it will never be calculated by the storage. Hence, finally the ASM disks will be shown without free space and will go offline while in reality there is a lot of space, but the storage cannot observe it.
To sum it up, I’ve founded the ASRU which is created especially for this purpose to solve this problem of storages, and I downloaded it. My question is that how can I take advantage of this utility? How am I supposed to install or run it? How can I attach it to oracle that make oracle aware of this utility as we need to use ASRU commands in sqlplus?
I’ll be thankful if any of you can navigate me to the right path.
I have never used this tool personally but while researching I have found lots of bugs related to block and disk corruption
This link has couple of example to use this tool
Using ASRU On Cloned Diskgroup may wipe out wrong disks (Doc ID 1519007.1)
These are defenitions. The pdf file which you kindly posted here a good source for the ones who want to know that what ASRU is, and what kind of problem can be solved by that.
In my case, I know what exactly it is, and I know it’s created for situations like mine, and it will solve my problem as long as I know how to take advantage of that.
I’ve downloaded ASRU, but I don’t know how to run.
But I appreciate your effort on replying me, and I’ll be happy if you or anyone else can lead me.
What is happening now in my server is that as much as the database grows, the storage will increase the used space but whenever we delete even a huge amount of database, it will never be calculated by the storage.
This sounds pretty normal and not an issue of ASM or Oracle. When you delete data in a tablespace, Oracle will not automatically compact a tablespace and release unused space back to the ASM storage. You will need to shrink the tablespace, e.g. using the Oracle Segment Advisor. ASM will then recognize the free space. If you drop a database, for instance, ASM will automatically increase the amount of free and usable space. The ASM usable space is the amount space that is available considering the level of data redundancy.
From what I understand, the ASRU utility was created for HP 3PAR storage systems. I'm not sure this is what you need unless this exactly what your are using.
That is somehow a different scenario, as we are using ASM on raw array of disks which is working in BLOCK LEVEL; therefore the storage array is unable to distinguish between capacity associated with deleted data and valid data.
That kind of utility which you kindly have mentioned is not gana work out here. (But I'll give it a try)
Have been using SAN based storage (raw LUNs) for over 10 years now. No idea about the problem you describe. (raw devices means block level storage and management)
Sounds like either buggy ASM s/w, buggy SAN, or both.
In which case the best solution would be to change to ASM latest, throw away buggy SAN, and get a decent storage layer. Or perhaps the first step is to throw Windows in the garbage can and install Oracle Linux instead.
Someone please correct me if I'm wrong, but from what I understand, the ASRU utility explained here is for 3PAR Thin Provisioning. It is a green storage technology that provides or distributes storage capacity as needed. This is different from a normal SAN or disk array, which provides a fixed space for use by ASM. Since the thin provisioning, unlike ASM knows nothing about how space is allocated inside ASM, the ASRU utility was developed to allow the storage system to reclaim unused space that was previously allocated by ASM back to the system's storage space distribution.
I do not see what ASM raw or block level access has to do with the need for such an utility. Block level (raw) access determines aspects of caching and performance. Space reclamation inside ASM, for instance to make room for additional datafiles, is done automatically during failure group rebalancing and tablespace compress and shrink operations at the database level, and last not least when dropping a database. To assume that deleting data in a tablespace will automatically free up disk space is simply wrong, and in this case the ASRU utility probably won't make a difference.