From mboxrd@z Thu Jan  1 00:00:00 1970
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Date: Tue, 09 Jul 2013 11:54:48 +0200
From: Zdenek Kabelac <zkabelac@redhat.com>
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Subject: Re: [linux-lvm] Very slow i/o after snapshotting
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To: LVM general discussion and development <linux-lvm@redhat.com>
Cc: Micky <mickylmartin@gmail.com>

Dne 9.7.2013 03:37, Micky napsal(a):
> On a machine, where weekly snapshots are created for dumping raw data,
> the overall disk i/o has drastically degraded to few megabytes per
> second. It is quite random and so slow that commands freeze often.
>
> I was using chunk size of 512K and same byte size with dd.
>
> Is it quite common; I read that such freezes require a reboot. Is
> there a way to avert?
> What am I missing here?

Is this supposed to be a bug report ?

I need crystal ball first ;)

So far I've no idea about disks/tables in use, system/kernel in use, lvm 
version in use....

Zdenek