snapshot with 2.6.5 kernel
Hello,
I am running a patched 2.6.5 kernel and using lvm2. Everything looks ok, but the snapshot may be having problems. Else I just may be ignorant about how to use the snapshot.
Here is what I am doing on a generic X86 server. I create a logical volume group out of a number of PEs that are properly configured. Then I create a logical volume. Then I start to dump a very large tar file into the logical volume. As this tar file is inflating the files into the logical volume, I then simultaneously create a snapshot volume of the recently created logical volume. The very large tar archive that was in the process of inflating its contents continues for a while, but finally just crashes and hangs at some point.
Am I missunderstanding how to use snapshot here? Or is this just severly broken software? Any advise is appreciated.
Thanks,
Karen
Signature · 3 lines
Karen Shaeffer Neuralscape, Palo Alto, Ca. 94306 [email protected] http://www.neuralscape.com
Quoted 16 lines · Karen Shaeffer
Hello,
I am running a patched 2.6.5 kernel and using lvm2. Everything looks ok, but the snapshot may be having problems. Else I just may be ignorant about how to use the snapshot.
Here is what I am doing on a generic X86 server. I create a logical volume group out of a number of PEs that are properly configured. Then I create a logical volume. Then I start to dump a very large tar file into the logical volume. As this tar file is inflating the files into the logical volume, I then simultaneously create a snapshot volume of the recently created logical volume. The very large tar archive that was in the process of inflating its contents continues for a while, but finally just crashes and hangs at some point.
Quoted 2 lines
Am I missunderstanding how to use snapshot here? Or is this just severly broken software? Any advise is appreciated.
You should be able to create a snapshot fine in ythat situation, even though the creation will happen slow under load.
Can you repeat the case ?
Do you have an oops ? If so, please provide the ksymoops output for further analysis of the problem.
Quoted 12 lines
Thanks,
KarenSignature · 8 lines
Karen Shaeffer Neuralscape, Palo Alto, Ca. 94306 [email protected] http://www.neuralscape.com _______________________________________________ linux-lvm mailing list [email protected] https://www.redhat.com/mailman/listinfo/linux-lvm read the LVM HOW-TO at http://tldp.org/HOWTO/LVM-HOWTO/
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Regards,
Heinz -- The LVM Guy --
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Nevertheless it needs not so stupid people to solve them ***
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Heinz Mauelshagen Red Hat GmbH
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=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-Quoted 9 lines · Heinz Mauelshagen
Quoted 6 lines · Karen Shaeffer
was in the process of inflating its contents continues for a while, but finally just crashes and hangs at some point.
Am I missunderstanding how to use snapshot here? Or is this just severly broken software? Any advise is appreciated.
Quoted 6 lines
You should be able to create a snapshot fine in ythat situation, even though the creation will happen slow under load.
Can you repeat the case ?
Do you have an oops ? If so, please provide the ksymoops output for further analysis of the problem.
Hello Heinz,
Sorry for the delay in responding, but I am very busy.
Yes, the problem is repeatable. The hardware included an external RAID array that was accessed with the LSI fibre channel HBA, which I believe is known to be buggy. So, I have removed this hardware from my test lab and will be conducting additional testing. I will provide full details, if I encounter additional problems.
BTW, can you please advise me of the time frame for progress with LVM2 and the 2.6.x kernel. Is a patchset planned to support the 2.6.6 kernel with respect to snapshot?
Also, can you comment on the evms alternative. It seems they already have a release supporting the 2.6.6 kernel. My understanding is that this latest evms release is production ready. Can you discuss LVM2's status in comparison?
Thanks,
Karen
Signature · 3 lines
Karen Shaeffer Neuralscape, Palo Alto, Ca. 94306 [email protected] http://www.neuralscape.com