[Lustre-discuss] o2iblnd no resources

[Isaac Huang]

On Sat, Feb 02, 2008 at 03:39:09PM +0800, Liang Zhen wrote:
> Hi Kilian,
> I think it's because o2iblnd uses fragmented RDMA by default(Max to 
> 256), so we have to set max_send_wr as (concurrent_send * (256 + 1)) 
> while creating QP by rdma_create_qp(), it takes a lot of resource and 
> can make a busy server out of memory sometime.
> To resolve this problem, we have to use FMR to map fragmented buffer to 
> virtual contiguous I/O address, there will always be one fragment for 
> RDMA by this way.
> Here is patch for this problem (using FMR in o2iblnd)
> https://bugzilla.lustre.org/attachment.cgi?id=15144

This is an experimental patch - nodes with the patch applied are not
interoperable with those without it. Please don't propagate the patch
to production systems.

Isaac