[pve-devel] drive-mirror, avoid pause if target storage is slow (block_set_io_throttle ? )

[Alexandre DERUMIER]

>> You already asked on the qemu-devel list? 

Not yet. 

My first tests seem to work, but I think it's difficult to find the good limit value (maybe it can be an vm config option, or param of qm move ?)

We can easily detect if target storage is too slow,  $stat->{offset} goes up and down 

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----- Mail original ----- 

De: "Dietmar Maurer" <dietmar at proxmox.com> 
À: "Alexandre DERUMIER" <aderumier at odiso.com>, pve-devel at pve.proxmox.com 
Envoyé: Mercredi 23 Janvier 2013 10:06:06 
Objet: RE: [pve-devel] drive-mirror, avoid pause if target storage is slow (block_set_io_throttle ? ) 

> I'm looking to find a way to get block-mirror correctly finish if target is slower 
> than source. 
> 
> Currently Michael have proposed to pause the vm, 
> 
> But maybe can we temporarily reduce the write speed on the source vm with 
> block_set_io_throttle (bps_wr or iops_wr) ? 

You already asked on the qemu-devel list?