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Subject: Re: [PATCH v6 4/5] NFSD: Implement NFSD_IO_DIRECT for NFS WRITE
From: Chuck Lever <cel@kernel.org>
To: NeilBrown <neil@brown.name>, Jeff Layton <jlayton@kernel.org>,
 Olga Kornievskaia <okorniev@redhat.com>, Dai Ngo <dai.ngo@oracle.com>,
 Tom Talpey <tom@talpey.com>
Cc: linux-nfs@vger.kernel.org, Mike Snitzer <snitzer@kernel.org>
References: <20251022192208.1682-1-cel@kernel.org>
 <20251022192208.1682-5-cel@kernel.org>
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On 10/22/25 3:22 PM, Chuck Lever wrote:
> @@ -1311,6 +1484,9 @@ nfsd_vfs_write(struct svc_rqst *rqstp, struct svc_fh *fhp,
>  	if (sb->s_export_op)
>  		exp_op_flags = sb->s_export_op->flags;
>  
> +	/* cel: UNSTABLE buffered WRITEs might want some form of throttling
> +	 *	as well to prevent clients from pushing writes to us faster
> +	 *	than they can be flushed onto durable storage */
>  	if (test_bit(RQ_LOCAL, &rqstp->rq_flags) &&
>  	    !(exp_op_flags & EXPORT_OP_REMOTE_FS)) {
>  		/*

Note: the above is an open question. I don't intend to merge this patch
with the above comment included.

-- 
Chuck Lever