From mboxrd@z Thu Jan  1 00:00:00 1970
From: bzzz.tomas at gmail.com <bzzz.tomas@gmail.com>
Date: Wed, 20 Oct 2010 21:18:59 +0400
Subject: [Lustre-devel] Queries regarding LDLM_ENQUEUE
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To: lustre-devel@lists.lustre.org

On 10/20/10 9:11 PM, Paul Nowoczynski wrote:
> I could be wrong but my guess is that the network congestion caused by
> this communication pattern is a more serious problem. The mds should be
> able to easily service lookup rpc's since only the first few necessitate
> a read I/O from the disk.

but then the network should be able to deal with storm of
<max RPC in-flight> * <# clients> to read/write data?

or it's a specific switch being the bottleneck to specific node?

because if it isn't network, but MDS being a real bottleneck,
then proxy might be a solution like Eric said above. not sure
is this important in your case, but this would allow to use
existing apps.

of course, distribution tree for a handle may scale better.

thanks, z