[linux-lvm] Server hangs when writing to LVM volume due to LVM Snapshots

[Tomasz Chmielewski]

Veselin Kantsev schrieb:
> Hello,
> I'm using LVM snapshots on the following configuration:
> 
> Debian lenny (2.6.24-1-amd64)
> 
> LVM version:     2.02.33 (2008-01-31)
> Library version: 1.02.24 (2007-12-20)
> Driver version:  4.12.0
> 
> 3ware 9000 Storage Controller device driver for Linux v2.26.02.010
> 
> I have a Logical volume running off a RAID5 for all my data.
> I recently started making daily LVM snapshots of this Logical volume.
> 
> The problem I'm experiencing now is that the server freezes if I try
> write a big chunk of data to the LVM volume.
> 
> Writing is OK on the second RAID (which holds the Debian OS)
> 
> Is there some known problem with writing lots of data to LVs while using
> LVM snapshots?

What is your RAM usage as you write to the snapshot?

Snapshots take some memory, and if you have lots of snapshots or they're 
just big, you can run out of memory.

Is it a possibility for you?


-- 
Tomasz Chmielewski
http://wpkg.org